EP0463948B1 - Process for dismantling an underground installation with risk of contamination and intervention box - Google Patents

Process for dismantling an underground installation with risk of contamination and intervention box

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Publication number
EP0463948B1
EP0463948B1 EP91401691A EP91401691A EP0463948B1 EP 0463948 B1 EP0463948 B1 EP 0463948B1 EP 91401691 A EP91401691 A EP 91401691A EP 91401691 A EP91401691 A EP 91401691A EP 0463948 B1 EP0463948 B1 EP 0463948B1
Authority
EP
European Patent Office
Prior art keywords
vessel
box
dismantled
section
vessel according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP91401691A
Other languages
German (de)
French (fr)
Other versions
EP0463948A1 (en
Inventor
François Bodin
Jean-Claude Saublet
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Orano Cycle SA
Original Assignee
Compagnie Generale des Matieres Nucleaires SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Compagnie Generale des Matieres Nucleaires SA filed Critical Compagnie Generale des Matieres Nucleaires SA
Publication of EP0463948A1 publication Critical patent/EP0463948A1/en
Application granted granted Critical
Publication of EP0463948B1 publication Critical patent/EP0463948B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F5/00—Transportable or portable shielded containers
    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
    • G21F5/00—Transportable or portable shielded containers
    • G21F5/06—Details of, or accessories to, the containers
    • G21F5/14—Devices for handling containers or shipping-casks, e.g. transporting devices loading and unloading, filling of containers

Definitions

  • the invention relates to a method of dismantling buried installations without shelter, at risk of radioactive contamination and possibly irradiating, in particular installations with linear extension such as disused effluent pipes.
  • non-contamination or “decontamination” means the state of a material for which its radioactivity is less than a predetermined threshold and given for example by the regulations in force.
  • Document US-A-4,813,313 describes an installation making it possible to dismantle the internal part, contaminated by radioactivity, of a wall previously used as protection for a nuclear reactor.
  • This installation includes a vertical pillar whose upper end is supported by a gantry resting on the upper surface of the wall.
  • the pillar supports devices capable of cutting the internal part of the wall and a gripping device capable of gripping the previously cut wall blocks, to evacuate them outside.
  • document EP-A-O 123 598 describes a mobile enclosure designed to ensure the replacement and the transport of a contaminated part of a nuclear installation.
  • the mobile enclosure comprises a rotary barrel with at least two cells, capable of receiving respectively the contaminated part and a new part.
  • the radioactivity of the cuttings and the excavation corresponding to the dismantled section is measured and any soil whose radioactivity exceeds a predetermined threshold is removed from the excavation to an appropriate storage area.
  • earthworks are carried out with a view to pre-clearing the sections according to the section being dismantled, during which the cuttings having a radioactivity above the predetermined threshold are temporarily stored in said box before their evacuation to the storage area.
  • the box further comprises a removable internal cover covering the central opening for temporarily isolating the interior of the box from the working area in which the section is being dismantled.
  • the box also comprises a suction device with a filter of the movable head type for capturing dust in this area.
  • the forced ventilation and suction devices are such that, after the removable internal cover has been put in place, the working area is in depression relative to the interior of the box and the interior of the box itself is in depression relative to the outside air.
  • the flexible curtain is constituted by a bellows one end of which is secured to the edges of the central opening and the other end of which carries a rigid frame capable of receiving said bellows when the latter is in the retracted position.
  • this bellows is maneuvered in the extended position or retracted by a winch lifting device associated with the frame.
  • two sides of the opening form a raceway for a carriage suspended in the opening.
  • the carriage carries a hydraulic shovel.
  • the tray has a reception area for a container accessible from a window with removable cover preferably located in the part forming the roof of the box and, optionally, a work area for the section being dismantled.
  • the tray also includes a reception area for a land receiving container, accessible from another window with a removable cover preferably located in the part forming the roof of the box.
  • the box comprises a hopper fitted with a helmet with controlled opening passing through the external envelope and opening above the reception area of the land reception container. This hopper accommodates contaminated earthmoving soil extracted by a hydraulic shovel with closed buckets located outside the box. Such an arrangement allows the confinement on the one hand of the debris of the installations being dismantled and on the other hand of the excavation and embankment soil which would be contaminated.
  • the box is constructed around two half-shells assembled in a removable manner on either side of a vertical median plane preferably parallel to the side of the largest dimension of the plate. -floor.
  • the central opening has a rectangular shape adapted to be positioned substantially in alignment with the unitary section to be dismantled.
  • reference 10 shows a trench open in the ground S to clear installations at risk of radioactive contamination and possibly irradiating, with large linear extension such as pipes, gutters, ducts, conduits , electric cables, etc.
  • a nonlimiting example of disused installations to be dismantled there is shown in section in FIG. 1 two metallic conduits 12 and a concrete sheath 14 consisting of an element 16 with a cross-section U shape called flue and a cover 18 formed of joined slabs (the interior of the sheath 14 being lined with other conduits and pipes not shown).
  • a movable intervention box 24 seen from the side by its "front" face (that is to say the face opposite the installation to be dismantled).
  • the box 24 has substantially the shape of a rectangular parallelepiped about 13 meters long by 5 meters wide and 4 meters high.
  • This box has a self-supporting structure produced around a very resistant floor plate 26 made of an assembly of steel beams (in particular the beams 25 and 27, and the U-beams, 29 and 31, seen in profile on the Figure 1) and capable of supporting, in addition to lifting and handling equipment, large loads of soil and / or debris from the installations to be dismantled.
  • the box 24 is moved and set up by a mobile crane (not shown) by means of a double set of “front” and “rear” slings, each consisting of high slings 28 integral with the hook of the crane and kept apart by a rigid tubular lifter 30, and low slings 32 arranged as illustrated in FIG. 1 between the lifter 30 and the floor plate 26, on each side of the box 24.
  • the roof 34 carries two pairs of vertical protections 36, the V-shaped end fittings of which are intended to receive the lifting beams 30 at rest and thus protect the roof 34.
  • the reference 22 represents a continuous concrete rail running along the pipes to be dismantled and the reference 20 represents a stud consisting of a concrete die 38 placed at the bottom of the trench or excavation 10 and d '' a tubular steel pillar 40 adjustable in height.
  • wooden planks 42 are arranged between the supports and the floor 26.
  • FIG. 2 illustrates a schematic view from above (roof removed) of the box 24 according to the invention.
  • Anchored on the floor plate 26 are arranged, along each long side of the box, five posts 44 (shown by the square sections) so as to define in the box four modules 41, 43, 45 and 47.
  • each "front" and “rear” side of the box has two adjoining twin posts 49 anchored on the floor plate 26.
  • the posts 44 carry cladding 46 forming a rigid external envelope and the roof 34.
  • the pads 20 are arranged in line with the posts 44 to ensure good load transfer. It should be noted that the use of studs proves to be well suited in sites with difficult access and where the available space is limited.
  • the plate 26 has a large elongated central opening 48 of substantially rectangular shape at the height of the modules 43 and 45 and through which the occupants of the box 24 have access to the conduits 12 and to the concrete sheath 14.
  • the edges of the opening 48 support four skirts 50 of plastic canvas coated with a double layer of vinyl (see Figures 1 and 3).
  • the four skirts 50 form a static confinement, a sort of protective curtain arranged around the central opening 48 to surround and isolate from the outside the working area in which the section is being dismantled.
  • the box 24 is provided with an airlock housed in the module 43.
  • the airlock is of a type with two compartments 52 and 54 produced by vinyl walls mounted on tubes and allows operator entry / exit operations by three doors shown schematically in Figure 2 by three double arrows.
  • the part of the roof opposite each module includes a large rectangular window 56 sealed with a removable cover 58.
  • Windows 56 mainly the windows corresponding to modules 41 and 47, are used to evacuate the earth from the excavation and special containers presented in detail below. -after.
  • the entire interior of the cladding 46 is lined with a double thickness of vinyl fabric (not shown) and ventilation in the box is ensured by a powerful filter group 60 at high flow rate (for example, 100 Nm3 / h) fitted with filters. interchangeable suitably adapted to retain inter alia contaminated dust.
  • the box is equipped with an atmospheric-type radiocontrol device with air sampling.
  • the box described here by way of nonlimiting example of a first embodiment of the invention has an interesting feature from the point of view of transport from one site to another; more precisely the box is pre-assembled into three sub-assemblies which are on the one hand the roof 34 and on the other hand two half-shells each formed by half of the self-supporting structure provided with its external cladding 46.
  • the two half-shells are assembled by bolts 62 at the beams 29 and 31 and twin posts 49, on either side of a vertical median plane P, P ′.
  • the half-shells structured around the two half-plates are capable of being easily transported by road on a trailer.
  • FIG. 2 The interior arrangement of the box is shown in FIG. 2 and, in part, in FIG. 3 which details the modules 41 and 43 in longitudinal section along the line A, A ′, A ⁇ , A ′′′ in FIG. 2.
  • the module 41 adjacent to the "front" face of the box houses a reception area for a steel or concrete container reinforced with fibers 64 intended to receive contaminated soil and a reception area 66 for the temporary storage of tools, for example the double clamshell bucket 68 shown in FIG. 3.
  • the clamshell bucket 68 is fixed to a hoist 70 itself associated with an overhead crane 72 capable of moving on two rails 74 covering the entire interior of the box and carried by the posts 44.
  • the hoist 70 can be used in combination with the clamshell bucket 68 with hydraulic closure to clean the excavation of the contaminated earth and / or to move large loads inside the box, for example the container 64 for receiving the earth or pieces of the concrete sheath 14 (in this case, the bucket 68 is temporarily stored on the area 66 consisting of a steel sheet with a rim covered with an interchangeable vinyl veil).
  • the container 64 for receiving the earth is placed under the mouth of a hopper 76 passing through the "front" wall of the box.
  • This hopper 76 allows temporary storage inside the contaminated earth box cleared by the adjustable hydraulic shovel with extendable arm 80 anchored on an external projection 82 of the pad- floor 26 (in FIG. 2, only the adjustable seat of the shovel is shown diagrammatically under the reference 80).
  • the shovel 80 is fitted with a clamshell bucket 84, the two buckets of which are closed with a protective plate and a hydraulic device 85 for orienting the buckets for precision work, the operator working from a control panel 86 placed next to a conventional pressurized fluid generator group 88.
  • the modules 43 and 45 of the box are mainly occupied by the rectangular central opening 48 which, for reasons of gain in volume, is offset with respect to the plane of symmetry P, P ′.
  • the opening 48 is aligned with the installations to be dismantled, that is to say the concrete sheath 14 (of which only the cover 18 is visible in FIG. 2) and the steel pipes 12.
  • the installations are thus directly accessible from inside the box.
  • the module 43 houses the airlock with its compartments 52 and 54 while the module 45 houses a reception area 90 for pieces of large dimensions of the installations.
  • FIG. 2 shows a unit element of approximately 3 meters (the flue 92) belonging to the concrete sheath to be dismantled.
  • the provisional reception area or work area 90 consists of a sheet of steel sheet ledge fitted with an interchangeable vinyl veil.
  • the length of the opening 48 has been chosen slightly greater than two lengths of flue 92 to correspond to two unit sections to be dismantled T1 and T2.
  • a carriage 94 suspended in the opening 48 is mounted on two rails formed by the beams 96 of the floor plate 26 which define the two long sides of the opening 48.
  • the carriage 94 is capable of receiving the container 64 for receiving the earth (as illustrated in 64a in FIGS. 2 and 3) during the cleaning phase of the excavation 10 and / or other debris presenting risks of contamination during the dismantling phase properly said.
  • Module 47 essentially houses a high-security standardized 98 anti-radiation container made of steel provided with an internal coating of concrete deposited transversely to the box.
  • This container 98 is intended to receive debris from installations after dismantling. In the present case, the capacity of the container allows the storage of the equivalent of four unitary sections of three meters.
  • the module 47 also houses an orientable jib 100 whose arm 102 carries an electric hoist 104 itself capable of carrying a certain number of tools such as hooks, self-tightening pliers, hydraulic clamp, saws, etc. This jib 100 is particularly intended for handling the pieces of the section being dismantled with a view to loading the container 98, either directly or after storage on the reception area 90.
  • the module 47 houses a second reception area (not shown) for the temporary storage of tools, consisting of a sheet steel plate with a rim fitted with an interchangeable vinyl sheeting.
  • the arrangement of the box is such that the dismantling work can be carried out with good radiation protection conditions in a relatively small volume.
  • the air space above the installation to be dismantled is widely used both for moving the box 24 and for the entry / exit movements of the container 64 for receiving the earth and the anti-radiation container 98 after release. covers 58 of the two windows 56 corresponding to modules 41 and 47.
  • the start-up of the box begins with the installation of a series of five studs 20 to the open air with an interval of 3 meters and the construction of the support rail 22 on either side of the routing of the pipes 12 and of the sheath 14 to be dismantled.
  • the box 24 is then placed above the first unitary sections to be dismantled, using a crane, then suitably wedged on the studs 20 and the rail 22.
  • the flexible vinyl curtain 50 is put in place, as well as two cofferdams at the "front” and at the "rear” of the box to collect rainwater. Only the water recovered at the "rear” of the box, that is to say in the sanitized area, will be discharged by pumping into the river network after inspection.
  • the pipes 12 and the concrete sheath 14 are then released in situ in their excavation 10 with the help of the inner skip 68.
  • the soil contaminated beyond a certain specific activity (for example, greater than 3700 Bq / kg) is then stored in containers 64 internally covered with vinyl.
  • the tiles forming the cover 18 of the sheath are checked and stored in the bottom of the container 98. This removal of the tiles is carried out over a length of 3 meters corresponding to a unitary section T1 to be dismantled (the length of the unitary section to be dismantled has been chosen at 3 meters depending on the unit length of a flue).
  • the separation of the flue thus released begins with a lifting using hoists and self-tightening pliers suitable, to allow the establishment in the bottom of the excavation 10 of a sheet of recovery of debris covered with a sheet of vinyl.
  • the flue 92 is then detached by cutting with a circular saw at the level of the cement joint existing between the flues. If necessary, the flue is cut using a hydraulic hammer. We then proceed to cut the elements lining the flue, such as plastic pipes, and temporarily store this debris in the carriage 94. It is possible for this purpose to use a basket (not shown) in place of the container 64.
  • the flue 92 is then removed from its excavation and deposited on the reception area 90 for control. Depending on the degree of radioactivity, the flue will either be evacuated through the roof of the box directly, or in the event of detected contamination (exceeding a determined threshold of mass radioactivity, for example 3700 Bq / kg) deposited in the anti-contamination container. radiation 98.
  • an anti-radiation container makes it possible to evacuate the debris corresponding to the dismantling of four unitary sections of 3 meters.
  • a hydraulic gripper capable of causing the walls of the flue to burst.
  • the measured mass activity is less than a first determined threshold (for example, 37 Bq / kg, the zone and the corresponding cuttings are considered to be healthy and inactive. If the mass activity is greater than this first threshold and less than a second determined threshold (for example, 3700 Bq / kg), questionable soil is removed with one of the bucket buckets to be transported to a monitored landfill Finally, if the mass activity is greater than this second threshold, the contaminated soil will be removed by one of the skips and stored in the container 64 for receiving the soil. If the external bucket is used, the contaminated soil is transported to the container 64 by the hopper 76.
  • a first determined threshold for example, 37 Bq / kg
  • a second determined threshold for example, 3700 Bq / kg
  • the dismantling of the second section T2 is then carried out as described above.
  • the external bucket 80 is used for the earthwork allowing the pre-clearance of the following sections and the positioning of the studs 20 at 3 meter intervals (the extracted earth being checked and sorted as previously described).
  • FIG. 4 shows another embodiment of an intervention box according to the invention.
  • This box with a structure similar to that of the box already described with reference to the figures 1 to 3, will not be described completely in detail.
  • similar or equivalent elements in the two boxes will bear the same reference number increased by 100.
  • Only the technical modifications and / or additions made to the box in FIG. 4 will be described in detail. Generally, the modifications and / or additions are intended to further improve protection against contamination during dismantling operations.
  • the box according to the invention 124 (shown in median longitudinal section) comprises a reinforced floor plate 126 carried by the pillars 40, 42 by means of support crosspieces 210 (shown in section transverse).
  • This arrangement makes it possible to increase the spacing between the pillars 40.
  • the support crosspieces are placed on sills (not shown) placed on each side of the excavation.
  • the floor plate 126 has a central opening 148 bordered by two beams 196 serving as rails for the carriage 194.
  • This carriage 194 has also been reinforced to carry a hydraulic shovel 180 with large elongation and whose buckets 184 are removable so that they can be replaced during certain operations by other suitable tools.
  • the shovel 180 is thus mobile with the carriage 194 in the opening 148 for depositing soil taken from the bottom of the excavation 10 in the container 64 (the reference 180a shows the shovel in another working position).
  • the steel-concrete container 98 is placed at the other end of the box 124 to be evacuated through the window 156 of the section 147.
  • the flexible protective curtain 150 intended to isolate the work area in the excavation from the outside, consists of a thick vinyl bellows, one end is secured to the edge of the central opening 148 and the other end of which carries a rigid frame 212 provided with a gutter intended to receive the bellows when the latter is in the retracted position (curtain raised).
  • the curtain 150 is maneuvered in the extended or retracted position (curtain lowered or raised) by a hoist lifting device of which we can see, in FIG. 4, only the operating belts 216.
  • the curtain 150 is lined internally with a double thickness of vinyl (not shown).
  • the box 124 comprises a rigid external envelope formed of posts 144 and of cladding 146 lined with vinyl and a roof 134 provided with windows 156.
  • the posts 144 carry the two rails 174 on which a traveling crane 172, carrying a hoist 170, is liable to move.
  • the box 124 includes a double airlock system (not shown) similar to that (52, 54) described with reference to the box 24.
  • the floor plan 126 is (unless otherwise stated ) substantially identical to that of the floor 26 of the box 24 illustrated in FIG. 2.
  • the box 124 is also assembled from two bolted half-shells according to the arrangement described for the box 24.
  • the working area 217 of the excavation 10, in which the section being dismantled is located, is temporarily isolated from the interior 219 of the box 124 by a removable internal cover 218 covering the central opening 148 and constituted by panels 220 aluminum covered with vinyl protection and placed on an internal partition 222 surrounding the opening 148.
  • This partition 222 carries lighting 224.
  • the collection of contaminated dust is produced by two independent ambient air purification systems in the box 124 and in the work area each having their battery of filters arranged inside the box.
  • the systems which are not illustrated in FIG. 4 consist of a forced ventilation system similar to that described under reference 60 for the box 24 and a suction device with a movable head capable of being placed in the immediate vicinity of the elements being dismantled (concrete sheath 14 or pipes 12).
  • the cover 218 allows improved containment of contaminated debris and increased protection for the occupants of the box. In general, it is sought to carry out as much dismantling work as possible when the internal cover 218 is in place on the partition 222 to ensure its insulation function. This is the case for cutting and preconditioning under vinyl of debris from pipes, slabs and flue.
  • the invention is not limited by the linear nature of the installations to be dismantled, here described by way of example; in particular the method according to the invention can be used for dismantling other types of construction with a possible adaptation of the box to the specifics of the site to be carried out.

Description

L'invention concerne un procédé de démantèlement d'installations enterrées hors abri, à risque de contamination radioactive et éventuellement irradiantes, notamment des installations à extension linéaire telles que des conduites d'effluents désaffectées.The invention relates to a method of dismantling buried installations without shelter, at risk of radioactive contamination and possibly irradiating, in particular installations with linear extension such as disused effluent pipes.

Dans le cadre d'une politique générale de protection contre les risques de contamination par radioactivité, il importe de procéder à l'élimination des déchets et autres installations susceptibles de contamination dès la mise hors-service de ces installations et de rendre disponibles à d'autres usages les zones occupées par ces dernières. En effet, même enfouies dans le sol, des canalisations pourraient à terme être détériorées et provoquer une dispersion de la contamination par infiltration et/ou ruissellement très difficile à contenir.As part of a general policy of protection against the risks of contamination by radioactivity, it is important to proceed with the elimination of waste and other installations liable to contamination as soon as these installations are decommissioned and to make available to other uses the areas occupied by the latter. Indeed, even buried in the ground, pipes could eventually be damaged and cause a dispersion of contamination by infiltration and / or runoff very difficult to contain.

D'une façon générale, on entend par état de non-contamination ou de décontamination, l'état d'un matériau pour lequel sa radioactivité est inférieure à un seuil prédéterminé et donné par exemple par la réglementation en vigueur.Generally, the term "non-contamination" or "decontamination" means the state of a material for which its radioactivity is less than a predetermined threshold and given for example by the regulations in force.

Le document US-A-4 813 313 décrit une installation permettant de démanteler la partie interne, contaminée par la radioactivité, d'une paroi servant auparavant de protection à un réacteur nucléaire. Cette installation comprend un pilier vertical dont l'extrémité haute est supportée par un portique reposant sur la surface supérieure de la paroi. Le pilier supporte des dispositifs aptes à découper la partie interne de la paroi et un dispositif de préhension apte à saisir les blocs de paroi préalablement découpés, pour les évacuer à l'extérieur.Document US-A-4,813,313 describes an installation making it possible to dismantle the internal part, contaminated by radioactivity, of a wall previously used as protection for a nuclear reactor. This installation includes a vertical pillar whose upper end is supported by a gantry resting on the upper surface of the wall. The pillar supports devices capable of cutting the internal part of the wall and a gripping device capable of gripping the previously cut wall blocks, to evacuate them outside.

Par ailleurs, le document EP-A-O 123 598 décrit une enceinte mobile conçue pour assurer le remplacement et le transport d'une pièce contaminée d'une installation nucléaire. A cet effet, l'enceinte mobile comprend un barillet rotatif à au moins deux alvéoles, aptes à recevoir respectivement la pièce contaminée et une pièce neuve.Furthermore, document EP-A-O 123 598 describes a mobile enclosure designed to ensure the replacement and the transport of a contaminated part of a nuclear installation. To this end, the mobile enclosure comprises a rotary barrel with at least two cells, capable of receiving respectively the contaminated part and a new part.

L'invention propose un procédé de démantèlement qui répond aux exigences de rigueur et de confinement impératives à tout travail en zone potentiellement sujette à radioactivité. Plus exactement, l'invention propose un procédé de démantèlement d'une installation, à risque de contamination et éventuellement irradiante selon lequel le démantèlement est effectué par tronçon unitaire de l'installation, sous couvert d'un caisson d'intervention déplaçable placé au-dessus du tronçon à démanteler, caractérisé en ce que, l'installation étant enterrée hors abri, le tronçon à démanteler est, après mise en place du caisson, successivement :

  • entouré d'une enveloppe de protection ;
  • dégagé in-situ dans sa fouille ;
  • séparé du reste de l'installation ;
  • mis en pièces dans le caisson ;
  • placé dans un conteneur entreposé dans le caisson ;
  • évacué hors du caisson, dans le conteneur.
The invention proposes a dismantling process which meets the requirements of rigor and confinement imperative to any work in an area potentially subject to radioactivity. More precisely, the invention proposes a method of dismantling an installation, at risk of contamination and possibly irradiating, according to which the dismantling is carried out by unitary section of the installation, under cover of a movable intervention box placed above the above the section to be dismantled, characterized in that, the installation being buried outside the shelter, the section to be dismantled is, after installation of the box, successively:
  • surrounded by a protective envelope;
  • cleared in situ in his excavation;
  • separated from the rest of the installation;
  • cut into pieces in the box;
  • placed in a container stored in the box;
  • evacuated from the box, into the container.

Par ailleurs, on procède à la mesure de la radioactivité des déblais et de la fouille correspondant au tronçon démantelé et on évacue de la fouille vers une aire de stockage appropriée toute terre dont la radioactivité dépasse un seuil prédéterminé. De façon optionnelle, on procède à un terrassement en vue d'un pré-dégagement des tronçons suivant le tronçon en cours de démantélement, pendant lequel les déblais présentant une radioactivité supérieure au seuil prédéterminé sont stockés de façon temporaire dans ledit caisson avant leur évacuation vers l'aire de stockage.In addition, the radioactivity of the cuttings and the excavation corresponding to the dismantled section is measured and any soil whose radioactivity exceeds a predetermined threshold is removed from the excavation to an appropriate storage area. Optionally, earthworks are carried out with a view to pre-clearing the sections according to the section being dismantled, during which the cuttings having a radioactivity above the predetermined threshold are temporarily stored in said box before their evacuation to the storage area.

Selon une variante du procédé de l'invention, on procède à la mise en place ae supports du caisson déplaçable, tels des plots ou un rail de soutènement, au fur et à mesure de l'avancement du démantèlement de l'installation, de part et d'autre de cette dernière. Le caisson est ensuite déplacé, par exemple par grutage. Ce choix de mise en place de supports provisoires tels que des plots est très avantageux à plusieurs titres :

  • il permet de positionner avec beaucoup de précision le caisson sur des terrains d'espace ou d'accès réduit et/ou sur des terrains accidentés ;
  • il permet de travailler dans la fouille sans risque d'éboulement ;
  • il permet une mise en place rapide des supports du caisson et par là-même peu onéreuse.
According to a variant of the method of the invention, one proceeds to the positioning of the supports of the movable box, such as studs or a retaining rail, as the dismantling of the installation progresses, in part and other of the latter. The box is then moved, for example by crane. This choice of setting up temporary supports such as studs is very advantageous for several reasons:
  • it allows the box to be positioned with great precision on terrain with limited space or access and / or on uneven terrain;
  • it allows you to work in the excavation without the risk of landslides;
  • it allows rapid installation of the supports of the box and therefore inexpensive.

l'invention concerne également un caisson d'intervention pour mettre en oeuvre dans ses diverses variantes le procédé exposé ci-dessus, le caisson comportant :

  • une structure autoporteuse réalisée autour d'un plateau-plancher muni d'une ouverture centrale, la structure supportant divers outils mobiles de levage et/ou de manutention et une enveloppe externe munie d'un sas et/ou d'au moins une fenêtre à capot amovible ;
  • un rideau de protection souple disposé autour de l'ouverture centrale pour ceinturer et isoler de l'extérieur une zone de travail dans laquelle est situé le tronçon en cours de démantèlement, la zone étant accessible à partir du caisson ;
  • un dispositif de ventilation forcée avec filtre, assurant un confinement dynamique pour épurer l'intérieur du caisson des poussières contaminées.
the invention also relates to an intervention box to implement in its various variants the process described above, the box comprising:
  • a self-supporting structure produced around a floor plate provided with a central opening, the structure supporting various mobile lifting and / or handling tools and an external envelope provided with an airlock and / or at least one window with removable cover;
  • a flexible protective curtain arranged around the central opening to surround and isolate from the outside a working area in which the section is being dismantled, the area being accessible from the box;
  • a forced ventilation device with filter, ensuring dynamic containment to purify the interior of the box of contaminated dust.

Selon une variante du caisson conforme à l'invention, le caisson comporte de plus un capot interne amovible recouvrant l'ouverture centrale pour isoler momentanément l'intérieur du caisson de la zone de travail dans laquelle est situé le tronçon en cours de démantèlement. Avantageusement, le caisson comporte également un dispositif d'aspiration avec filtre du type à tête mobile pour capter les poussières dans cette zone. Dans un mode de réalisation particulier de cette variante, les dispositifs de ventilation forcée et d'aspiration sont tels, qu'après mise en place du capot interne amovible, la zone de travail se trouve en dépression par rapport à l'intérieur du caisson et l'intérieur du caisson se trouve lui-même en dépression par rapport à l'air extérieur.According to a variant of the box according to the invention, the box further comprises a removable internal cover covering the central opening for temporarily isolating the interior of the box from the working area in which the section is being dismantled. Advantageously, the box also comprises a suction device with a filter of the movable head type for capturing dust in this area. In a particular embodiment of this variant, the forced ventilation and suction devices are such that, after the removable internal cover has been put in place, the working area is in depression relative to the interior of the box and the interior of the box itself is in depression relative to the outside air.

Selon une autre variante du caisson conforme à l'invention, le rideau souple est constitué par un soufflet dont une extrémité est solidarisée aux bords de l'ouverture centrale et dont l'autre extrémité porte un cadre rigide susceptible de recevoir ledit soufflet lorsque celui-ci est en position rétractée. Avantageusement, ce soufflet est manoeuvré en position étendue ou rétracté par un dispositif de relevage à treuil associé au cadre.According to another variant of the box according to the invention, the flexible curtain is constituted by a bellows one end of which is secured to the edges of the central opening and the other end of which carries a rigid frame capable of receiving said bellows when the latter is in the retracted position. Advantageously, this bellows is maneuvered in the extended position or retracted by a winch lifting device associated with the frame.

Selon encore une autre variante du caisson conforme à l'invention, deux côtés de l'ouverture forment un chemin de roulement pour un chariot suspendu dans l'ouverture. Avantageusement, le chariot porte une pelle hydraulique.According to yet another variant of the box according to the invention, two sides of the opening form a raceway for a carriage suspended in the opening. Advantageously, the carriage carries a hydraulic shovel.

Selon une autre variante de réalisation du caisson conforme à l'invention, le plateau possède une aire d'accueil pour un conteneur accessible à partir d'une fenêtre à capot amovible située de préférence dans la partie formant le toit du caisson et, éventuellement, une aire de travail pour le tronçon en cours de démantèlement. Avantageusement, le plateau comporte également une aire d'accueil pour un conteneur de réception des terres, accessible à partir d'une autre fenêtre à capot amovible située de préférence dans la partie formant le toit du caisson. De façon optionnelle, le caisson comporte une trémie munie d'un casque à ouverture commandée traversant l'enveloppe externe et débouchant au-dessus de l'aire d'accueil du conteneur de réception des terres. Cette trémie accueille de la terre de terrassement contaminée extraite par une pelle hydraulique à godets fermés située à l'extérieur du caisson. Un tel agencement permet le confinement d'une part des débris des installations en cours de démantèlement et d'autre part des terres de fouille et de remblai qui seraient contaminées.According to another alternative embodiment of the box according to the invention, the tray has a reception area for a container accessible from a window with removable cover preferably located in the part forming the roof of the box and, optionally, a work area for the section being dismantled. Advantageously, the tray also includes a reception area for a land receiving container, accessible from another window with a removable cover preferably located in the part forming the roof of the box. Optionally, the box comprises a hopper fitted with a helmet with controlled opening passing through the external envelope and opening above the reception area of the land reception container. This hopper accommodates contaminated earthmoving soil extracted by a hydraulic shovel with closed buckets located outside the box. Such an arrangement allows the confinement on the one hand of the debris of the installations being dismantled and on the other hand of the excavation and embankment soil which would be contaminated.

Selon encore une autre variante du caisson conforme à l'invention, le caisson est construit autour de deux demi-coques assemblées de façon démontable de part et d'autre d'un plan médian vertical parallèle de préférence au côté de plus grande dimension du plateau-plancher.According to yet another variant of the box according to the invention, the box is constructed around two half-shells assembled in a removable manner on either side of a vertical median plane preferably parallel to the side of the largest dimension of the plate. -floor.

Selon encore une autre variante du caisson conforme à l'invention et utilisable notamment pour le démantèlement d'installations à extension linéaire, l'ouverture centrale présente une forme rectangulaire adaptée pour être positionnée sensiblement en alignement avec le tronçon unitaire à démanteler.According to yet another variant of the box according to the invention and usable in particular for the dismantling of installations with linear extension, the central opening has a rectangular shape adapted to be positioned substantially in alignment with the unitary section to be dismantled.

L'invention est maintenant décrite en se référant aux dessins ci-annexés dans lesquels :

  • la figure 1 représente une vue de côté d'un premier mode de réalisation d'un caisson selon l'invention en place au-dessus du tronçon à démanteler lui-même vu en coupe transversale ;
  • la figure 2 représente un plan schématique vu du dessus (toit enlevé) du caisson illustré à la figure 1 ;
  • la figure 3 représente une vue en coupe partielle longitudinale selon la ligne A-A′-A˝-A‴ de la figure 2 du caisson illustré à la figure 1 ; et
  • la figure 4 représente une vue en coupe longitudinale d'un second mode de réalisation d'un caisson selon l'invention.
The invention is now described with reference to the accompanying drawings in which:
  • Figure 1 shows a side view of a first embodiment of a box according to the invention in place above the section to be dismantled itself seen in cross section;
  • 2 shows a schematic plan seen from above (roof removed) of the box illustrated in Figure 1;
  • 3 shows a longitudinal partial sectional view along the line AA′-A˝-A ‴ of Figure 2 of the box illustrated in Figure 1; and
  • FIG. 4 represents a view in longitudinal section of a second embodiment of a box according to the invention.

Si l'on considère la figure 1, la référence 10 montre une tranchée ouverte dans le sol S pour dégager des installations à risque de contamination radioactive et éventuellement irradiantes, à grande extension linéaire telles que des conduites, des caniveaux, des gaines, des canalisations, des câbles électriques, etc.. A titre d'exemple non limitatif d'installations désaffectées à démanteler, on a représenté en coupe sur la figure 1 deux conduites métalliques 12 et une gaine en béton 14 constituée d'un élément 16 à section en forme de U dénommé carneau et d'un couvercle 18 formé de dalles jointes (l'intérieur de la gaine 14 étant garni d'autres conduites et canalisations non représentées).If we consider Figure 1, reference 10 shows a trench open in the ground S to clear installations at risk of radioactive contamination and possibly irradiating, with large linear extension such as pipes, gutters, ducts, conduits , electric cables, etc. As a nonlimiting example of disused installations to be dismantled, there is shown in section in FIG. 1 two metallic conduits 12 and a concrete sheath 14 consisting of an element 16 with a cross-section U shape called flue and a cover 18 formed of joined slabs (the interior of the sheath 14 being lined with other conduits and pipes not shown).

Au-dessus de la tranchée 10 est disposé sur des supports 20 et 22 un caisson d'intervention déplaçable 24 vu de côté par sa face "avant" (c'est-à-dire la face en regard de l'installation à démanteler). Le caisson 24 a sensiblement la forme d'un parallélépipède rectangle d'environ 13 mètres de long sur 5 mètres de large et 4 mètres de hauteur. Ce caisson présente une structure autoporteuse réalisée autour d'un plateau-plancher 26 très résistant fait d'un assemblage de poutrelles d'acier (notamment les poutrelles 25 et 27, et les poutrelles en U, 29 et 31, vues de profil sur la figure 1) et susceptible de supporter, outre des engins de levage et de manutention, des charges importantes de terre et/ou de débris des installations à démanteler.Above trench 10 is arranged on supports 20 and 22 a movable intervention box 24 seen from the side by its "front" face (that is to say the face opposite the installation to be dismantled). The box 24 has substantially the shape of a rectangular parallelepiped about 13 meters long by 5 meters wide and 4 meters high. This box has a self-supporting structure produced around a very resistant floor plate 26 made of an assembly of steel beams (in particular the beams 25 and 27, and the U-beams, 29 and 31, seen in profile on the Figure 1) and capable of supporting, in addition to lifting and handling equipment, large loads of soil and / or debris from the installations to be dismantled.

Le caisson 24 est déplacé et mis en place par une grue mobile (non représentée) par l'intermédiaire d'un double jeu d'élingues "avant" et "arrière", chacun constitué d'élingues hautes 28 solidaires du crochet de la grue et maintenues écartées par un palonnier tubulaire rigide 30, et d'élingues basses 32 disposées comme illustré sur la figure 1 entre le palonnier 30 et le plateau-plancher 26, de chaque côté du caisson 24.The box 24 is moved and set up by a mobile crane (not shown) by means of a double set of “front” and “rear” slings, each consisting of high slings 28 integral with the hook of the crane and kept apart by a rigid tubular lifter 30, and low slings 32 arranged as illustrated in FIG. 1 between the lifter 30 and the floor plate 26, on each side of the box 24.

Par ailleurs, le toit 34 porte deux paires de protections verticales 36 dont les ferrures d'extrémité en forme de V sont destinées à recevoir les palonniers 30 au repos et à protéger ainsi le toit 34.Furthermore, the roof 34 carries two pairs of vertical protections 36, the V-shaped end fittings of which are intended to receive the lifting beams 30 at rest and thus protect the roof 34.

Compte tenu des charges importantes à supporter, il importe de réaliser des supports de caisson robustes et de les mettre en place avec beaucoup de soin. A titre d'exemple non limitatif, la référence 22 représente un rail en béton continu courant le long des conduites à démanteler et la référence 20 représente un plot constitué d'un dé en béton 38 placé au fond de la tranchée ou fouille 10 et d'un pilier d'acier tubulaire 40 réglable en hauteur. Pour parfaire l'équilibrage du caisson 24 sur ses supports 20 et 22, des madriers de bois 42 sont disposés entre les supports et le plancher 26.Given the large loads to bear, it is important to make robust box supports and to install them with great care. By way of nonlimiting example, the reference 22 represents a continuous concrete rail running along the pipes to be dismantled and the reference 20 represents a stud consisting of a concrete die 38 placed at the bottom of the trench or excavation 10 and d '' a tubular steel pillar 40 adjustable in height. To perfect the balancing of the box 24 on its supports 20 and 22, wooden planks 42 are arranged between the supports and the floor 26.

La figure 2 illustre une vue schématique du dessus (toit enlevé) du caisson 24 selon l'invention. Ancrés sur le plateau-plancher 26 sont disposés, le long de chaque grand côté du caisson, cinq poteaux 44 (montrés par les sections carrées) de façon à définir dans le caisson quatre modules 41, 43, 45 et 47. Par ailleurs, chaque face "avant" et "arrière" du caisson présente deux poteaux jumeaux accolés 49 ancrés sur le plateau-plancher 26. Les poteaux 44 portent un bardage 46 formant une enveloppe externe rigide et le toit 34. Comme on peut le voir sur la figure 2, les plots 20 sont disposés au droit des poteaux 44 pour assurer un bon transfert de charge. Il est à noter que l'utilisation des plots s'avère bien adaptée dans des chantiers d'accès difficile et où l'espace disponible est limité.FIG. 2 illustrates a schematic view from above (roof removed) of the box 24 according to the invention. Anchored on the floor plate 26 are arranged, along each long side of the box, five posts 44 (shown by the square sections) so as to define in the box four modules 41, 43, 45 and 47. Furthermore, each "front" and "rear" side of the box has two adjoining twin posts 49 anchored on the floor plate 26. The posts 44 carry cladding 46 forming a rigid external envelope and the roof 34. As can be seen in FIG. 2 , the pads 20 are arranged in line with the posts 44 to ensure good load transfer. It should be noted that the use of studs proves to be well suited in sites with difficult access and where the available space is limited.

Le plateau 26 comporte une large ouverture centrale allongée 48 de forme sensiblement rectangulaire à la hauteur des modules 43 et 45 et par laquelle les occupants du caisson 24 ont accès aux conduites 12 et à la gaine de béton 14. Pour assurer une bonne protection et une isolation de l'extérieur, les bords de l'ouverture 48 supportent quatre jupes 50 en toile plastique enduite d'une double couche de vinyl (voir les figures 1 et 3). Les quatre jupes 50 forment un confinement statique, sorte de rideau de protection disposé autour de l'ouverture centrale 48 pour ceinturer et isoler de l'extérieur la zone de travail dans laquelle est situé le tronçon en cours de démantèlement.The plate 26 has a large elongated central opening 48 of substantially rectangular shape at the height of the modules 43 and 45 and through which the occupants of the box 24 have access to the conduits 12 and to the concrete sheath 14. To provide good protection and insulation from the outside, the edges of the opening 48 support four skirts 50 of plastic canvas coated with a double layer of vinyl (see Figures 1 and 3). The four skirts 50 form a static confinement, a sort of protective curtain arranged around the central opening 48 to surround and isolate from the outside the working area in which the section is being dismantled.

Le caisson 24 est muni d'un sas logé dans le module 43. Le sas est d'un type à deux compartiments 52 et 54 réalisés par des parois vinyl montées sur tubes et permet les opérations d'entrée/sortie des opérateurs par trois portes schématisées à la figure 2 par trois doubles flèches. La partie du toit en vis-à-vis de chaque module comporte une fenêtre rectangulaire de grande taille 56 fermée de façon étanche par un capot amovible 58. Les fenêtres 56, principalement les fenêtres correspondant aux modules 41 et 47, sont utilisées pour évacuer la terre de la fouille et des conteneurs spéciaux présentés en détail ci-après. Tout l'intérieur du bardage 46 est tapissé d'une double épaisseur de toile vinyl (non représentée) et la ventilation dans le caisson est assurée par un puissant groupe filtrant 60 à fort débit (par exemple, 100 Nm³/h) muni de filtres interchangeables convenablement adaptés pour retenir entre autres les poussières contaminées. Bien entendu, le caisson est équipé d'un appareil de radiocontrôle de type atmosphérique à prélèvement d'air.The box 24 is provided with an airlock housed in the module 43. The airlock is of a type with two compartments 52 and 54 produced by vinyl walls mounted on tubes and allows operator entry / exit operations by three doors shown schematically in Figure 2 by three double arrows. The part of the roof opposite each module includes a large rectangular window 56 sealed with a removable cover 58. Windows 56, mainly the windows corresponding to modules 41 and 47, are used to evacuate the earth from the excavation and special containers presented in detail below. -after. The entire interior of the cladding 46 is lined with a double thickness of vinyl fabric (not shown) and ventilation in the box is ensured by a powerful filter group 60 at high flow rate (for example, 100 Nm³ / h) fitted with filters. interchangeable suitably adapted to retain inter alia contaminated dust. Of course, the box is equipped with an atmospheric-type radiocontrol device with air sampling.

Le caisson ici décrit à titre d'exemple non limitatif d'un premier mode de réalisation de l'invention présente une particularité intéressante du point de vue du transport d'un chantier à un autre ; plus exactement le caisson est pré-assemblé en trois sous-ensembles qui sont d'une part le toit 34 et d'autre part deux demi-coques formées chacune de la moitié de la structure autoporteuse munie de son bardage externe 46. Comme on peut le voir sur les figures 1 et 2, les deux demi-coques sont assemblées par des boulons 62 au niveau des poutrelles 29 et 31 et des poteaux jumeaux 49, de part et d'autre d'un plan médian vertical P, P′. Ainsi, les demi-coques structurées autour des deux demi-plateaux sont susceptibles d'être aisément transportées par la route sur remorque.The box described here by way of nonlimiting example of a first embodiment of the invention has an interesting feature from the point of view of transport from one site to another; more precisely the box is pre-assembled into three sub-assemblies which are on the one hand the roof 34 and on the other hand two half-shells each formed by half of the self-supporting structure provided with its external cladding 46. As can be see in Figures 1 and 2, the two half-shells are assembled by bolts 62 at the beams 29 and 31 and twin posts 49, on either side of a vertical median plane P, P ′. Thus, the half-shells structured around the two half-plates are capable of being easily transported by road on a trailer.

L'agencement intérieur du caisson est montré sur la figure 2 et, pour partie, sur la figure 3 qui détaille les modules 41 et 43 en coupe longitudinale selon la ligne A, A′,A˝, A‴ de la figure 2. Le module 41 adjacent à la face "avant" du caisson abrite une aire d'accueil pour un conteneur d'acier ou de béton renforcé de fibres 64 destiné à recevoir de la terre contaminée et une aire d'accueil 66 pour l'entrepôt provisoire d'outils, par exemple la double benne-preneuse 68 montrée à la figure 3.The interior arrangement of the box is shown in FIG. 2 and, in part, in FIG. 3 which details the modules 41 and 43 in longitudinal section along the line A, A ′, A˝, A ‴ in FIG. 2. The module 41 adjacent to the "front" face of the box houses a reception area for a steel or concrete container reinforced with fibers 64 intended to receive contaminated soil and a reception area 66 for the temporary storage of tools, for example the double clamshell bucket 68 shown in FIG. 3.

La benne-preneuse 68 est fixée à un palan 70 lui-même associé à un pont-roulant 72 susceptible de se déplacer sur deux rails 74 couvrant tout l'intérieur du caisson et portés par les poteaux 44. Le palan 70 peut être utilisé en combinaison avec la benne-preneuse 68 à fermeture hydraulique pour nettoyer la fouille de la terre contaminée et/ou pour déplacer des charges importantes à l'intérieur du caisson, par exemple le conteneur 64 de réception des terres ou des morceaux de la gaine de béton 14 (dans ce cas, la benne 68 est entreposée provisoirement sur l'aire 66 constituée d'une tôle d'acier à rebord recouverte d'un voile de vinyl interchangeable). Dans sa position usuelle représentée sur les figures 2 et 3, le conteneur 64 de réception des terres est disposé sous la bouche d'une trémie 76 traversant la paroi "avant" du caisson. Cette trémie 76 dont l'entrée externe est contrôlée par un casque 78 à commande hydraulique, permet le stockage temporaire à l'intérieur du caisson de terre contaminée déblayée par la pelle hydraulique orientable à bras extensible 80 ancrée sur une avancée externe 82 du pateau-plancher 26 (sur la figure 2, seule l'assise orientable de la pelle est représentée schématiquement sous la référence 80).The clamshell bucket 68 is fixed to a hoist 70 itself associated with an overhead crane 72 capable of moving on two rails 74 covering the entire interior of the box and carried by the posts 44. The hoist 70 can be used in combination with the clamshell bucket 68 with hydraulic closure to clean the excavation of the contaminated earth and / or to move large loads inside the box, for example the container 64 for receiving the earth or pieces of the concrete sheath 14 (in this case, the bucket 68 is temporarily stored on the area 66 consisting of a steel sheet with a rim covered with an interchangeable vinyl veil). In its usual position shown in FIGS. 2 and 3, the container 64 for receiving the earth is placed under the mouth of a hopper 76 passing through the "front" wall of the box. This hopper 76, the external input of which is controlled by a helmet 78 with hydraulic control, allows temporary storage inside the contaminated earth box cleared by the adjustable hydraulic shovel with extendable arm 80 anchored on an external projection 82 of the pad- floor 26 (in FIG. 2, only the adjustable seat of the shovel is shown diagrammatically under the reference 80).

La pelle 80 est équipée d'une benne-preneuse 84 dont les deux godets sont fermés d'une tôle de protection et d'un dispositif hydraulique d'orientation 85 des godets pour les travaux de précision, l'opérateur travaillant à partir d'un tableau de commande 86 disposé à côté d'un groupe générateur de fluide sous pression classique 88.The shovel 80 is fitted with a clamshell bucket 84, the two buckets of which are closed with a protective plate and a hydraulic device 85 for orienting the buckets for precision work, the operator working from a control panel 86 placed next to a conventional pressurized fluid generator group 88.

Si l'on considère à nouveau la figure 2, les modules 43 et 45 du caisson sont principalement occupés par l'ouverture centrale rectangulaire 48 qui, pour des raisons de gain de volume, est décalée par rapport au plan de symétrie P, P′. Toutefois, on peut remarquer que l'ouverture 48 est alignée sur les installations à démanteler, c'est-à-dire la gaine de béton 14 (dont seul le couvercle 18 est visible sur la figure 2) et les conduites en acier 12. Les installations sont ainsi directement accessibles à partir de l'intérieur du caisson. Le module 43 abrite le sas avec ses compartiments 52 et 54 tandis que le module 45 abrite une aire d'accueil 90 pour des morceaux de dimension importante des installations. A titre d'exemple, la figure 2 montre un élément unitaire d'environ 3 mètres (le carneau 92) appartenant à la gaine en béton à démanteler. cet élément appartient au tronçon unitaire T1 en cours de démantèlement et représenté en pointillé sur la figure 2. Comme pour l'aire 66, l'aire d'accueil provisoire ou aire de travail 90 est constituée d'une plaque de tôle d'acier à rebord muni d'un voile de vinyl interchangeable. Pour des raisons de rendement, la longueur de l'ouverture 48 a été choisie légèrement supérieure à deux longueurs de carneau 92 pour correspondre à deux tronçons unitaires à démanteler T1 et T2. Pour terminer la description des modules 43 et 45, un chariot 94 suspendu dans l'ouverture 48 est monté sur deux rails constitués par les poutrelles 96 du plateau-plancher 26 qui définissent les deux grands côtés de l'ouverture 48. Le chariot 94 est susceptible d'accueillir le conteneur 64 de réception des terres (comme illustré en 64a sur les figures 2 et 3) pendant la phase de nettoyage de la fouille 10 et/ou d'autres débris présentant des risques de contamination pendant la phase de démantèlement proprement dite.If we look again at Figure 2, the modules 43 and 45 of the box are mainly occupied by the rectangular central opening 48 which, for reasons of gain in volume, is offset with respect to the plane of symmetry P, P ′. However, it can be noted that the opening 48 is aligned with the installations to be dismantled, that is to say the concrete sheath 14 (of which only the cover 18 is visible in FIG. 2) and the steel pipes 12. The installations are thus directly accessible from inside the box. The module 43 houses the airlock with its compartments 52 and 54 while the module 45 houses a reception area 90 for pieces of large dimensions of the installations. By way of example, FIG. 2 shows a unit element of approximately 3 meters (the flue 92) belonging to the concrete sheath to be dismantled. this element belongs to the unitary section T1 being dismantled and shown in dotted lines in FIG. 2. As for area 66, the provisional reception area or work area 90 consists of a sheet of steel sheet ledge fitted with an interchangeable vinyl veil. For reasons of efficiency, the length of the opening 48 has been chosen slightly greater than two lengths of flue 92 to correspond to two unit sections to be dismantled T1 and T2. To complete the description of the modules 43 and 45, a carriage 94 suspended in the opening 48 is mounted on two rails formed by the beams 96 of the floor plate 26 which define the two long sides of the opening 48. The carriage 94 is capable of receiving the container 64 for receiving the earth (as illustrated in 64a in FIGS. 2 and 3) during the cleaning phase of the excavation 10 and / or other debris presenting risks of contamination during the dismantling phase properly said.

Le module 47 abrite essentiellement un conteneur anti-radiation 98 de haute sécurité normalisé en acier pourvu d'un revêtement interne de béton déposé transversalement par rapport au caisson. Ce conteneur 98 est destiné à accueillir les débris des installations après démantèlement. Dans le cas présent, la capacité du conteneur permet la mise en stockage de l'équivalent de quatre tronçons unitaires de trois mètres. Le module 47 abrite également une potence orientable 100 dont le bras 102 porte un palan électrique 104 lui-même susceptible de porter un certain nombre d'outils tels que crochets, pinces auto-serreuses, pince hydraulique, scies, etc.. Cette potence 100 est particulièrement destinée à la manipulation des morceaux du tronçon en cours de démantèlement en vue du chargement du conteneur 98, soit directement, soit après entreposage sur l'aire d'accueil 90. Pour finir, le module 47 abrite une seconde aire d'accueil (non représentée) pour l'entrepôt provisoire des outils, constituée d'une plaque de tôle d'acier à rebord munie d'un voile de vinyl interchangeable.Module 47 essentially houses a high-security standardized 98 anti-radiation container made of steel provided with an internal coating of concrete deposited transversely to the box. This container 98 is intended to receive debris from installations after dismantling. In the present case, the capacity of the container allows the storage of the equivalent of four unitary sections of three meters. The module 47 also houses an orientable jib 100 whose arm 102 carries an electric hoist 104 itself capable of carrying a certain number of tools such as hooks, self-tightening pliers, hydraulic clamp, saws, etc. This jib 100 is particularly intended for handling the pieces of the section being dismantled with a view to loading the container 98, either directly or after storage on the reception area 90. Finally, the module 47 houses a second reception area (not shown) for the temporary storage of tools, consisting of a sheet steel plate with a rim fitted with an interchangeable vinyl sheeting.

Comme on peut le constater de la description précédente, l'agencement du caisson est tel que le travail de démantèlement peut être effectué avec de bonnes conditions de protection contre les rayonnements dans un volume relativement restreint. Par ailleurs, on utilise largement l'espace aérien au-dessus de l'installation à démanteler tant pour déplacer le caisson 24 que pour les mouvements d'entrée/sortie du conteneur 64 de réception des terres et du conteneur anti-radiation 98 après dégagement des capots 58 des deux fenêtres 56 correspondant aux modules 41 et 47.As can be seen from the previous description, the arrangement of the box is such that the dismantling work can be carried out with good radiation protection conditions in a relatively small volume. In addition, the air space above the installation to be dismantled is widely used both for moving the box 24 and for the entry / exit movements of the container 64 for receiving the earth and the anti-radiation container 98 after release. covers 58 of the two windows 56 corresponding to modules 41 and 47.

La mise en oeuvre du procédé selon l'invention à l'aide du caisson qui vient d'être décrit est effectuée de la façon suivante : la mise en route du caisson commence par la mise en place d'une série de cinq plots 20 à l'air libre avec un intervalle de 3 mètres et la confection du rail de soutènement 22 de part et d'autre du cheminement des conduites 12 et de la gaine 14 à démanteler.The implementation of the method according to the invention using the box which has just been described is carried out as follows: the start-up of the box begins with the installation of a series of five studs 20 to the open air with an interval of 3 meters and the construction of the support rail 22 on either side of the routing of the pipes 12 and of the sheath 14 to be dismantled.

Comme pour tous les travaux de terrassement et de fouille, les déblais sont systématiquement contrôlés pour permettre leur tri selon le degré de leur radioactivité par unité de poids (mesuré par exemple en Becquerel/kg ou Bq/kg). Ce contrôle est réalisé par des opérateurs en tenue de radio-protection avec l'aide d'appareils portatifs de comptage des désintégrations des radioéléments éventuellement présents. On réalise ainsi une pré-fouille dont la profondeur est déterminée soit :

  • par arrêt à 10 cm environ au-dessus des dalles du carneau ;
  • par dépassement d'un seuil déterminé (par exemple, 3700 Bq/kg) pour l'activité massique des terres dégagées.
As with all earthworks and excavation, the cuttings are systematically checked to allow their sorting according to the degree of their radioactivity per unit of weight (measured for example in Becquerel / kg or Bq / kg). This control is carried out by operators in radio protection clothing with the help of portable devices for counting the decay of radioactive elements that may be present. A pre-excavation is thus carried out, the depth of which is determined either:
  • by stopping approximately 10 cm above the slabs of the flue;
  • by exceeding a determined threshold (for example, 3700 Bq / kg) for the mass activity of cleared land.

Le caisson 24 est ensuite mis en place au-dessus des premiers tronçons unitaires à démanteler, à l'aide d'une grue, puis convenablement calé sur les plots 20 et le rail 22.The box 24 is then placed above the first unitary sections to be dismantled, using a crane, then suitably wedged on the studs 20 and the rail 22.

Pour parfaire l'isolation de la zone de travail, on met en place le rideau souple de vinyl 50, ainsi que deux batardeaux à l'"avant" et à I'"arrière" du caisson pour recueillir les eaux de pluie. Seules les eaux récupérées à I'"arrière" du caisson, c'est-à-dire en zone assainie seront rejetées par pompage dans le réseau fluvial après contrôle.To improve the insulation of the work area, the flexible vinyl curtain 50 is put in place, as well as two cofferdams at the "front" and at the "rear" of the box to collect rainwater. Only the water recovered at the "rear" of the box, that is to say in the sanitized area, will be discharged by pumping into the river network after inspection.

Les conduites 12 et la gaine de béton 14 sont ensuite dégagées in-situ dans leur fouille 10 avec l'aide de la benne intérieure 68. La terre contaminée au-delà d'une certaine activité massique (par exemple, supérieure à 3700 Bq/kg) est alors stockée dans des conteneurs 64 recouverts intérieurement de vinyl. Les dalles formant la couverture 18 de la gaine sont contrôlées et stockées dans le fond du conteneur 98. Ce retrait des dalles est effectué sur une longueur de 3 mètres correspondant à un tronçon unitaire T1 à démanteler (la longueur du tronçon unitaire à démanteler a été choisie à 3 mètres en fonction de la longueur unitaire d'un carneau). La séparation du carneau ainsi dégagé commence par un soulèvement à l'aide de palans et pinces auto-serreuses appropriés, pour permettre la mise en place dans le fond de la fouille 10 d'une tôle de récupération de débris recouverte d'une nappe de vinyl. De façon optionnelle, il est prévu de percer les parois du carneau pour faciliter sa préhension.The pipes 12 and the concrete sheath 14 are then released in situ in their excavation 10 with the help of the inner skip 68. The soil contaminated beyond a certain specific activity (for example, greater than 3700 Bq / kg) is then stored in containers 64 internally covered with vinyl. The tiles forming the cover 18 of the sheath are checked and stored in the bottom of the container 98. This removal of the tiles is carried out over a length of 3 meters corresponding to a unitary section T1 to be dismantled (the length of the unitary section to be dismantled has been chosen at 3 meters depending on the unit length of a flue). The separation of the flue thus released begins with a lifting using hoists and self-tightening pliers suitable, to allow the establishment in the bottom of the excavation 10 of a sheet of recovery of debris covered with a sheet of vinyl. Optionally, it is planned to pierce the walls of the flue to facilitate its gripping.

Le carneau 92 est alors détaché par découpage à la scie circulaire au niveau du joint de ciment existant entre les carneaux. En cas de besoin, le carneau est coupé à l'aide d'un marteau hydraulique. On procède ensuite à la découpe des éléments garnissant le carneau, tels que des conduites plastiques, et au stockage provisoire de ces débris dans le chariot 94. Il est possible à cet effet d'utiliser un panier (non représenté) en lieu et place du conteneur 64. Le carneau 92 est ensuite enlevé de sa fouille puis déposé sur l'aire d'accueil 90 pour contrôle. Selon le degré de la radioactivité, le carneau sera soit évacué par le toit du caisson directement, soit en cas de contamination décelée (dépassement d'un seuil déterminé de radioactivité massique, par exemple de 3700 Bq/kg) déposé dans le conteneur anti-radiation 98.The flue 92 is then detached by cutting with a circular saw at the level of the cement joint existing between the flues. If necessary, the flue is cut using a hydraulic hammer. We then proceed to cut the elements lining the flue, such as plastic pipes, and temporarily store this debris in the carriage 94. It is possible for this purpose to use a basket (not shown) in place of the container 64. The flue 92 is then removed from its excavation and deposited on the reception area 90 for control. Depending on the degree of radioactivity, the flue will either be evacuated through the roof of the box directly, or in the event of detected contamination (exceeding a determined threshold of mass radioactivity, for example 3700 Bq / kg) deposited in the anti-contamination container. radiation 98.

L'élimination des conduites métalliques 12 est alors effectuée par tronçon de 3 mètres selon le même principe, avec installation préalable d'un plateau de récupération des débris de sciage. Les tronçons sciés sont également disposés dans le conteneur anti-radiation 98. Lorsque ce conteneur 98 est plein, il est évacué du caisson par grutage au travers du toit 34, puis dirigé vers une zone de stockage appropriée. Dans l'exemple de mise en oeuvre du procédé selon l'invention ici décrit, un conteneur anti-radiation permet d'évacuer les débris correspondant au démantèlement de quatre tronçons unitaires de 3 mètres. A titre de variante, il est possible pour gagner de la place de mettre en pièces le carneau par l'utilisation d'outils appropriés par exemple une pince hydraulique suscpetible de faire éclater les parois du carneau.The elimination of the metal pipes 12 is then carried out in sections of 3 meters according to the same principle, with prior installation of a tray for collecting sawdust. The sawn sections are also placed in the anti-radiation container 98. When this container 98 is full, it is evacuated from the box by crane through the roof 34, then directed towards an appropriate storage area. In the example of implementation of the method according to the invention described here, an anti-radiation container makes it possible to evacuate the debris corresponding to the dismantling of four unitary sections of 3 meters. As a variant, it is possible to save space to tear the flue apart by the use of appropriate tools, for example a hydraulic gripper capable of causing the walls of the flue to burst.

On procède enfin au contrôle de la fouille proprement dite (sol et parois). Si l'activité massique mesurée est inférieure à un premier seuil déterminé (par exemple, 37 Bq/kg, la zone et les déblais correspondants sont considérés comme sains et inactifs. Si l'activité massique est supérieure à ce premier seuil et inférieure à un deuxième seuil déterminé (par exemple, 3700 Bq/kg), la terre douteuse est enlevée avec une des bennes à godets pour être transportée vers une décharge surveillée. Enfin, si l'activité massique est supérieure à ce deuxième seuil, la terre contaminée sera enlevée par une des bennes et stockée dans le conteneur 64 de réception des terres. En cas d'utilisation de la benne extérieure, la terre contaminée est acheminée dans le conteneur 64 par la trémie 76.Finally, we proceed to control the actual excavation (ground and walls). If the measured mass activity is less than a first determined threshold (for example, 37 Bq / kg, the zone and the corresponding cuttings are considered to be healthy and inactive. If the mass activity is greater than this first threshold and less than a second determined threshold (for example, 3700 Bq / kg), questionable soil is removed with one of the bucket buckets to be transported to a monitored landfill Finally, if the mass activity is greater than this second threshold, the contaminated soil will be removed by one of the skips and stored in the container 64 for receiving the soil. If the external bucket is used, the contaminated soil is transported to the container 64 by the hopper 76.

Le démantèlement du second tronçon T2 est ensuite effectué comme décrit ci-avant. Entre temps, la benne extérieure 80 est utilisée pour le terrassement permettant le pré-dégagement des tronçons suivants et la mise en place des plots 20 à intervalle de 3 mètres (la terre extraite étant contrôlée et triée comme précédemment décrit).The dismantling of the second section T2 is then carried out as described above. In the meantime, the external bucket 80 is used for the earthwork allowing the pre-clearance of the following sections and the positioning of the studs 20 at 3 meter intervals (the extracted earth being checked and sorted as previously described).

Après contrôle et évacuation des eaux de pluie, il est alors possible de déplacer le caisson par grutage.After control and evacuation of rainwater, it is then possible to move the box by crane.

Le caisson illustré à la figure 4 montre un autre mode de réalisation d'un caisson d'intervention selon l'invention. Ce caisson, de structure similaire de celle du caisson déjà décrit en référence aux figures 1 à 3, ne sera pas décrit complètement en détail. En particulier, les éléments semblables ou équivalents dans les deux caissons porteront le même numéro de référence augmenté de 100. Seules les modifications et/ou ajouts techniques apportés au caisson de la figure 4 seront décrits en détail. D'une façon générale, les modifications et/ou ajouts ont pour but d'améliorer encore la protection contre la contamination lors des opérations de démantèlement.The box illustrated in FIG. 4 shows another embodiment of an intervention box according to the invention. This box, with a structure similar to that of the box already described with reference to the figures 1 to 3, will not be described completely in detail. In particular, similar or equivalent elements in the two boxes will bear the same reference number increased by 100. Only the technical modifications and / or additions made to the box in FIG. 4 will be described in detail. Generally, the modifications and / or additions are intended to further improve protection against contamination during dismantling operations.

Si l'on considère la figure 4, le caisson selon l'invention 124 (représenté en coupe longitudinale médiane) comporte un plateau-plancher 126 renforcé porté par les piliers 40, 42 par l'intermédiaire de traverses de soutènement 210 (représentées en section transversale). Cette disposition permet d'accroître l'espacement entre les piliers 40. A titre de variante, les traverses de soutènement sont posées sur des longrines (non représentées) mises en place de chaque côté de la fouille. Le plateau-plancher 126 présente une ouverture centrale 148 bordée par deux poutrelles 196 servant de rails au chariot 194. Ce chariot 194 a été également renforcé pour porter une pelle hydraulique 180 à grand allongement et dont les godets 184 sont amovibles pour être remplacés lors de certaines opérations par d'autres outils adéquats. La pelle 180 est ainsi mobile avec le chariot 194 dans l'ouverture 148 pour déposer de la terre prise en fond de fouille 10 dans le conteneur 64 (la référence 180a montre la pelle dans une autre position de travail).If we consider Figure 4, the box according to the invention 124 (shown in median longitudinal section) comprises a reinforced floor plate 126 carried by the pillars 40, 42 by means of support crosspieces 210 (shown in section transverse). This arrangement makes it possible to increase the spacing between the pillars 40. As a variant, the support crosspieces are placed on sills (not shown) placed on each side of the excavation. The floor plate 126 has a central opening 148 bordered by two beams 196 serving as rails for the carriage 194. This carriage 194 has also been reinforced to carry a hydraulic shovel 180 with large elongation and whose buckets 184 are removable so that they can be replaced during certain operations by other suitable tools. The shovel 180 is thus mobile with the carriage 194 in the opening 148 for depositing soil taken from the bottom of the excavation 10 in the container 64 (the reference 180a shows the shovel in another working position).

Comme précédemment, le conteneur acier-béton 98 est disposé à l'autre extrémité du caisson 124 pour être évacué par la fenêtre 156 de la tranche 147.As before, the steel-concrete container 98 is placed at the other end of the box 124 to be evacuated through the window 156 of the section 147.

Le rideau souple de protection 150, destiné à isoler la zone de travail dans la fouille de l'extérieur, est constitué par un soufflet de vinyl épais dont une extrémité est solidarisée avec le bord de l'ouverture centrale 148 et dont l'autre extrémité porte un cadre rigide 212 muni d'une gouttière destinée à recevoir le soufflet lorsque celui-ci est en position rétractée (rideau relevé). Le rideau 150 est manoeuvré en position étendue ou rétractée (rideau baissé ou relevé) par un dispositif de relevage à treuil dont on ne voit, sur la figure 4, que les courroies de manoeuvre 216. Pour parfaire la protection contre la contamination, le rideau 150 est doublé intérieurement d'une double épaisseur de vinyl (non représenté).The flexible protective curtain 150, intended to isolate the work area in the excavation from the outside, consists of a thick vinyl bellows, one end is secured to the edge of the central opening 148 and the other end of which carries a rigid frame 212 provided with a gutter intended to receive the bellows when the latter is in the retracted position (curtain raised). The curtain 150 is maneuvered in the extended or retracted position (curtain lowered or raised) by a hoist lifting device of which we can see, in FIG. 4, only the operating belts 216. To perfect the protection against contamination, the curtain 150 is lined internally with a double thickness of vinyl (not shown).

De façon déjà présentée pour le caisson 24, le caisson 124 comporte une enveloppe externe rigide formée des poteaux 144 et d'un bardage 146 doublé de vinyl et un toit 134 muni des fenêtres 156. Les poteaux 144 portent les deux rails 174 sur lesquels un pont-roulant 172, porteur d'un palan 170, est susceptible de se déplacer. Par ailleurs, le caisson 124 comporte un système de double sas (non représenté) semblable à celui (52, 54) décrit en référence au caisson 24. D'une façon générale, le plan d'occupation du plancher 126 est (sauf mention particulière) sensiblement identique à celui du plancher 26 du caisson 24 illustré à la figure 2. Par ailleurs, le caisson 124 est également assemblé à partir de deux demi-coques boulonnées selon l'agencement décrit pour le caisson 24.As already presented for the box 24, the box 124 comprises a rigid external envelope formed of posts 144 and of cladding 146 lined with vinyl and a roof 134 provided with windows 156. The posts 144 carry the two rails 174 on which a traveling crane 172, carrying a hoist 170, is liable to move. Furthermore, the box 124 includes a double airlock system (not shown) similar to that (52, 54) described with reference to the box 24. In general, the floor plan 126 is (unless otherwise stated ) substantially identical to that of the floor 26 of the box 24 illustrated in FIG. 2. Furthermore, the box 124 is also assembled from two bolted half-shells according to the arrangement described for the box 24.

La zone de travail 217 de la fouille 10, dans laquelle est situé le tronçon en cours de démantèlement, est isolée momentanément de l'intérieur 219 du caisson 124 par un capot interne amovible 218 recouvrant l'ouverture centrale 148 et constitué par des panneaux 220 en aluminium recouverts d'une protection de vinyl et posés sur une cloison interne 222 ceinturant l'ouverture 148. Cette cloison 222 porte un éclairage 224.The working area 217 of the excavation 10, in which the section being dismantled is located, is temporarily isolated from the interior 219 of the box 124 by a removable internal cover 218 covering the central opening 148 and constituted by panels 220 aluminum covered with vinyl protection and placed on an internal partition 222 surrounding the opening 148. This partition 222 carries lighting 224.

La collecte des poussières contaminées est réalisée par deux systèmes indépendants de purification de l'air ambiant dans le caisson 124 et dans la zone de travail présentant chacun leur batterie de filtres disposés à l'intérieur du caisson. Les systèmes qui ne sont pas illustrés sur la figure 4 se composent d'un système de ventilation forcé analogue à celui décrit sous la référence 60 pour le caisson 24 et un dispositif d'aspiration à tête mobile susceptible d'être placé au voisinage immédiat des éléments en cours de démantèlement (gaine de béton 14 ou conduites 12).The collection of contaminated dust is produced by two independent ambient air purification systems in the box 124 and in the work area each having their battery of filters arranged inside the box. The systems which are not illustrated in FIG. 4 consist of a forced ventilation system similar to that described under reference 60 for the box 24 and a suction device with a movable head capable of being placed in the immediate vicinity of the elements being dismantled (concrete sheath 14 or pipes 12).

Ces systèmes de purification présentent un débit d'air moyen de l'ordre de 100 Nm³/h. Leurs caractéristiques de travail sont telles que, lorsque le capot 218 amovible est en place (capot fermé), la zone de travail 217 se trouve en dépression par rapport à l'intérieur du caisson 219, lui-même en dépression par rapport à l'extérieur (air atmosphérique).These purification systems have an average air flow of around 100 Nm³ / h. Their working characteristics are such that, when the removable cover 218 is in place (closed cover), the working area 217 is in depression with respect to the interior of the box 219, itself in depression with respect to the outside (atmospheric air).

La mise en oeuvre du procédé selon l'invention avec le caisson 124 est semblable à celle décrite avec le caisson 24. Toutefois, le capot 218 permet un confinement amélioré des débris contaminés et une protection accrue pour les occupants du caisson. D'une façon générale, on cherche à exécuter le plus possible de travaux de démantèlement lorsque le capot interne 218 est en place sur la cloison 222 pour assurer sa fonction d'isolation. Il en est ainsi pour les découpes et le préconditionnement sous vinyl des débris des conduites, des dalles et du carneau.The implementation of the method according to the invention with the box 124 is similar to that described with the box 24. However, the cover 218 allows improved containment of contaminated debris and increased protection for the occupants of the box. In general, it is sought to carry out as much dismantling work as possible when the internal cover 218 is in place on the partition 222 to ensure its insulation function. This is the case for cutting and preconditioning under vinyl of debris from pipes, slabs and flue.

Bien entendu, l'invention n'est pas limitée par le caractère linéaire des installations à démanteler, ici décrites à titre d'exemple ; en particulier le procédé selon l'invention peut être utilisé pour le démantèlement d'autres types de constructions avec une éventuelle adaptation du caisson aux spécificités du chantier à réaliser.Of course, the invention is not limited by the linear nature of the installations to be dismantled, here described by way of example; in particular the method according to the invention can be used for dismantling other types of construction with a possible adaptation of the box to the specifics of the site to be carried out.

Claims (22)

  1. Process for dismantling an installation (12, 14) having a possible risk of contamination and possibly of an irradiating nature, according to which dismantling takes place by unitary installation section (T1, T2), under the cover of a displaceable intervention vessel (24) placed above the section (T1, T2) to be dismantled, characterized in that the installation is buried in unsheltered form after the vessel (24, 124) is put into place, the section (T1) to be dismantled is sucessively:
    - surrounded by a protective envelope (50, 150); then
    - disengaged on site in its trench (10);
    - separated from the rest of the equipment;
    - put into the vessel (24, 124) in pieces;
    - placed in a container (98) that is in the vessel;
    - evacuated from the vessel in the container (98).
  2. Process according to claim 1, characterized in that the radioactivity of the waste and the ditch (10) of the dismantled section (T1) is measured and any earth whose radioactivity exceeds a predetermined threshold is evacuated from the ditch to an appropriate storage area.
  3. Process according to claim 2, characterized in that there is terracing for releasing the sections after the section (T1, T2) being dismantled, during which any waste with a radioactivity above a predetermined threshold is stored temporarily in said vessel before it is evacuated to the storage area.
  4. Process according to any one of the preceding claims, characterized in that the work is done with the equipment on the moving vessel supports, such as blocks (20) or a supporting rail (22), as the equipment (12, 14) is dismantled on both sides of this equipment (12, 14).
  5. Process according to claim 4, characterized in that the vessel (24, 124) is moved by crane.
  6. Process according to any one of the preceding claims, characterized in that this process is used for dismantling equipment that extends linearly, particularly off-line pipes that may be protected by concrete sheathing (14).
  7. Intervention vessel for performing the process according to any one of the preceding claims, characterized in that it comprises:
    - a self-supporting structure (26-44-49, 126-144) built around a deck (26, 126) equipped with a central opening (48, 148), said structure supporting various mobile lifting equipment and/or handling equipment (70, 104, 170) and an outside envelope (46, 146) equipped with a lock chamber (52, 54) and/or at least one window (56, 156) with a mobile cover (58);
    - a flexible protective curtain (50, 150) around the central opening (48, 148) to surround and insulate from the outside a work area in which the section (T1, T2) being dismantled is located, said area being accessible from the vessel;
    - a forced ventilation system (60) with filter, ensuring dynamic confinement to clean the inside of the vessel of contaminated dust.
  8. Vessel according to claim 7, characterized in that a moving inside cover (218) covers the central opening (148) to insulate the inside (219) of the vessel for a certain period of time from the work area (217) in which the section being dismantled is located.
  9. Vessel according to either of the claims 7 and 8, characterized in that it has a suction device with a filter having a moving head to pick up the contaminated dust is placed in said work area.
  10. Vessel according to claims 7 and 9, in combination, characterized in that the forced ventilation and suction devices are such that after the detachable inside head (218) is installed, the work area is placed under vacuum in relation to the inside (219) of the vessel and the inside (219) of the vessel is under vacuum in relation to the outside air.
  11. Vessel according to any one of the claims 7 to 10, characterized in that said flexible curtain (150) is composed of a bellows, one end of which is joined to the edges of the central opening (148) and the other end of which has a rigid frame (212, 214) that can take said bellows (150) when it is retracted.
  12. Vessel according to claim 11, characterized in that said bellows is manoeuvred in extended or retracted position by a winch lifting device associated with said frame (216).
  13. Vessel according to any one of the claims 7 to 12, characterized in that said deck (26) has a holding area for a container (98) accessible from a window (50, 150) with a detachable hood (58) located preferably in the part forming the roof (34, 134) of the vessel and possibly a work area (90) for the section (92) being dismantled.
  14. Vessel according to any one of the claims 7 to 13, characterized in that a mobile rolling bridge (72, 172) is placed above the deck and adapted optionally to carry a hydraulic closing bucket (68).
  15. Vessel according to any one of the claims 7 to 14, characterized in that it has an adjustable bracket crane (100) equipped with a block and tackle (104).
  16. Vessel according to any one of the claims 7 to 15, characterized in that said deck (26, 126) has a holding area for a container (64) to take soil, accessible from a second window (56, 156) with a detachable hood (58) located preferably in the part forming the roof (34, 134) of the vessel.
  17. Vessel according to claim 16, characterized in that there is a hopper (76) equipped with a controlled opening helmet (18) crossing said external envelope (48) and opening above the holding area of the soil container (64).
  18. Vessel according to any one of the claims 7 to 17, characterized in that said deck includes an outside head (82) on which a closed bucket (84) hydraulic scoop (80) is mounted.
  19. Vessel according to any one of the claims 7 to 18, characterized in that two sides of the central opening (48, 148) form a patch for a cart (94, 194) suspended in said central opening.
  20. Vessel according to claim 19, characterized in that said cart (194) has a hydraulic scoop (180).
  21. Vessel according to any one of the claims 7 to 20, characterized in that it is built around two half shells assembled so they can be disassembled on both sides of a vertical median plane (P, P′) preferably parallel to the largest sides of the deck (26, 126).
  22. Vessel according to any one of the claims 7 to 21, usable especially for dismantling equipment (12, 14) that extends in a straight line, characterized in that the central opening (48, 148) has a rectangular shape adapted to be positioned substantially in alignment with the section (T1, T2) to be dismantled.
EP91401691A 1990-06-25 1991-06-21 Process for dismantling an underground installation with risk of contamination and intervention box Expired - Lifetime EP0463948B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9007948 1990-06-25
FR909007948A FR2663777B1 (en) 1990-06-25 1990-06-25 PROCESS FOR DISMANTLING AN UNDERGROUND, SHELTERED INSTALLATION, AT RISK OF CONTAMINATION AND POSSIBLY IRRADIATING, AND INTERVENTIONAL BOX FOR IMPLEMENTING THIS PROCESS.

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EP0463948A1 EP0463948A1 (en) 1992-01-02
EP0463948B1 true EP0463948B1 (en) 1995-03-08

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US (1) US5278877A (en)
EP (1) EP0463948B1 (en)
CZ (1) CZ194691A3 (en)
DE (1) DE69107911T2 (en)
FR (1) FR2663777B1 (en)
HU (1) HUT60339A (en)
SK (1) SK280439B6 (en)

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JP7241010B2 (en) * 2019-12-25 2023-03-16 三菱重工業株式会社 Guide method for working device and processing device for radioactive waste

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0123598A1 (en) * 1983-04-13 1984-10-31 Commissariat A L'energie Atomique Mobile flask for the replacement and transport of contaminated items and complementary holder for such a flask
US4813313A (en) * 1985-11-25 1989-03-21 Kabushiki Kaisha Kobe Seiko Sho Apparatus for demolishing a reactor shield wall

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3910006A (en) * 1973-06-07 1975-10-07 Westinghouse Electric Corp Fuel element handling arrangement and method
US4410802A (en) * 1976-04-15 1983-10-18 Szulinski Milton J Storage depot for radioactive material
DE2854330C2 (en) * 1978-12-15 1983-01-05 Alfred Kunz GmbH & Co, 8000 München Procedure for the disposal of decommissioned nuclear power plants
DE2929467C2 (en) * 1979-07-20 1985-04-25 Kraftwerk Union AG, 4330 Mülheim Storage building for spent nuclear reactor fuel elements
FR2487106A1 (en) * 1980-07-15 1982-01-22 Commissariat Energie Atomique SYSTEM FOR REPLACING AN ORGAN OF A CONTAMINATED FLUID CIRCUIT AND METHOD OF REPLACING IT
US4681706A (en) * 1984-07-05 1987-07-21 Westinghouse Electric Corp. Nuclear waste packaging facility
FR2596565B1 (en) * 1986-04-01 1988-07-01 Cogema PROCESS FOR FITTING A BEAM OF PENCILS OF A NUCLEAR FUEL ASSEMBLY AND INSTALLATION FOR CARRYING OUT SAID METHOD
GB2222196B (en) * 1988-02-08 1991-07-17 Kunz Alfred & Co A process for lowering a building structure into the ground

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0123598A1 (en) * 1983-04-13 1984-10-31 Commissariat A L'energie Atomique Mobile flask for the replacement and transport of contaminated items and complementary holder for such a flask
US4813313A (en) * 1985-11-25 1989-03-21 Kabushiki Kaisha Kobe Seiko Sho Apparatus for demolishing a reactor shield wall

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HUT60339A (en) 1992-08-28
CZ194691A3 (en) 1994-08-17
SK194691A3 (en) 2000-02-14
EP0463948A1 (en) 1992-01-02
US5278877A (en) 1994-01-11
SK280439B6 (en) 2000-02-14
HU912121D0 (en) 1991-12-30
DE69107911T2 (en) 1995-11-02
DE69107911D1 (en) 1995-04-13
FR2663777B1 (en) 1994-06-17
FR2663777A1 (en) 1991-12-27

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