FR2678311A1 - Tool, method and equipment for demolition of walls, particularly of chimneys - Google Patents

Abstract

The invention relates to the demolition of a wall, more particularly of the wall (2) of a chimney (40) with the aid of a tool (1) including, mounted in opposition at the ends of the jaws (3, 4), a rock breaker (7) and a bearing shoe (8). This tool is suspended from a crane (15) carried by annular scaffolding (16), which is supported by six links (46) incorporating thrust cylinders (21) fastened to the top edge (23) of the chimney. After this chimney has been demolished over a height (h), the scaffolding is lowered by the same height by actuating the thrust cylinders (21).

Description

Wall demolition tool, process and equipment,
especially chimneys
The present invention firstly relates to a wall demolition tool, in particular of reinforced concrete, comprising a pair of articulated jaws provided with a means for controlling the spacing of their ends, which carry attack members mounted in opposition which are brought on either side of a wall to be demolished by straddling it by the pair of jaws.

 The invention aims to create a tool of this kind, of simple structure and increased efficiency.

 To this end, the drive members of the tool according to the invention consist firstly of a rock breaker mounted on one of the jaws, its perforating spike being directed towards the end of the other jaw , and secondly by a support shoe mounted on the latter, facing said perforating spike; in addition, the conformation of the support shoe and of the means for connecting the latter to the jaw which carries it is such that, when the jaws close, the perforating spike can pass through the shoe without encountering any obstacle.

 Such a tool, of remarkably simple structure since it comprises only a single rock breaker, has the advantage of offering the latter, thanks to the shoe which it comprises on its other branch, a firm and stable support on the wall. to be demolished to resume the reaction forces developed by the jerky efforts to penetrate the wall exerted by the pickpick. The complementary punch-anvil assembly formed by the latter with the support shoe ensures optimum performance for the tool. In addition, the support shoe, although arranged in alignment with the rock breaker spike, is not opposed to its progression, which can freely cross the wall to come out of the other cat, nor to the evacuation of the masonry debris then formed, which favors the speed of fracturing of the wall by the breaker.

 At least one of its jaws should be provided with attachment means enabling it to be suspended from the cable of a lifting device. Depending on the number and position of these attachment means, the tool can work with its rock breaker oriented horizontally (when the wall to be demolished is vertical), the tool coming to straddle the wall either from above or laterally, or vertically (for a horizontal wall to be demolished).

 The invention also relates to a method of demolishing a tubular masonry veil with a vertical axis, in particular made of reinforced concrete, such as a chimney, making use of the tool defined above.

 This process consists in installing around the top of the tubular veil an annular scaffolding carrying a crane to the boom of which the demolition tool is suspended, to attack and demolish by successive panels, using the latter, the top part of the tubular veil on the extent of a crown of determined height, to bring down the scaffolding by an amount equal to this height, to attack and demolish in the same way the new summit part on said height, and so on not step by step to the foot of the tubular veil.

 In an advantageous embodiment, the scaffolding is supported by suspension, using links of variable length on command, at the top edge of the veil either initial, or born from the demolition of the part of the veil which surmounted it. According to another characteristic of the invention, these links, hooked to said top edge, are unhooked in turn to allow the demolition of a sail panel where they were respectively hung, each of them then being hung up on the new edge summit resulting from the demolition of said panel, following which is ordered a reduction in the length of the corresponding link so as to restore it to its function of supporting the scaffolding.

 Furthermore, the implementation of such links makes it possible to carry out each step of descent of the scaffolding by ordering an identical elongation for each of the links which support it.

 Initially, before the demolition work begins, the scaffolding must be hoisted to the top of the tubular veil to be demolished. This can be achieved using a set of flexible links of variable length on order, each of which is attached by one end to the scaffolding at one of several points distributed around the periphery thereof, climbs pass on a stationary pulley installed at the top of the sail, then descends to attach to the scaffolding at a point close to the aforementioned point, by alternately ordering a reduction in the length of some of these links, then re-tensioning of the other links .

The invention also relates to a material making it possible to implement the demolition process previously defined. This material includes
- an annular scaffolding,
- A set of scaffolding support links by suspension at the top edge of the tubular veil, these links, each of which is of adjustable length on command and can be hung on or off the said edge, being distributed around the periphery of the scaffolding in sufficient number so that any of them can be removed without compromising the stability of the scaffolding suspended by the other links, and
- a crane carried by the scaffolding, to the boom from which the demolition tool is suspended, this crane being designed to allow the breaker of this tool to be brought to any point on a top part of the tubular sail s 'extending over a crown of determined height.

 Preferably, each of the aforementioned links includes a jack for varying its length and a temporary attachment member to said top edge, the link being attached to the scaffolding via the jack.

 In view of the prior hoisting, at the top of the tubular web, of the scaffolding, to this can be fixed, near each jack, a traction device acting as a winch, by which a cable of cable can be attached to the scaffolding. prior hoisting thereof, this cable, after passing over a pulley mounted at the top of the veil, returning to attach to the scaffolding by means of said jack.

 In the case where the masonry web to be demolished is not cylindrical, being for example a frustoconical chimney, provision should be made for the scaffolding to be radially expandable, which can be obtained in a simple manner when the scaffolding is formed of several sectors assembled in a ring by means of connecting elements of adjustable length whose adjustment makes it possible to modify the mutual spacing of the sectors, therefore the diameter of the scaffolding.

 Other characteristics and advantages of the invention will emerge from the description which follows, with reference to the appended drawings, of nonlimiting exemplary embodiments.

 Figure 1 shows, in elevation, a demolition tool according to the invention.

 2 shows a view along arrow II of a part of the object of Figure 1, with half-section.

 Figures 3 and 4 show, in perspective, two alternative embodiments of the tool of Figure 1.

 Figure 5 shows, in vertical section and in a simplified manner, the top of a chimney being demolished using the equipment according to the invention.

 Figure 6 illustrates, in perspective, a phase of demolition of the chimney.

 Figures 7 to 9 schematically illustrate the successive operations of prior hoisting of the annular scaffolding forming part of the demolition equipment.

 Figure 10 shows in plan an expandable annular scaffolding, the two halves shown being adjusted to a different diameter.

 FIG. 11 represents a partial view along arrow XI of the object of FIG. 1.

 The demolition tool 1 represented in FIG. 1 is intended to carry out the demolition of a masonry wall such as the wall 2. I1 comprises a pair of jaws 3, 4 articulated along an axis 5, one of which comprises an attachment part 6 by which the tool can be suspended from a lifting machine. In the suspended situation, the jaws 3, 4 extend downward, so that they can be brought to either side of the top of the wall 2 to be demolished. At the end of the jaw 3 is mounted a rock breaker or hydraulic hammer 7 whose attack member 7a, constituted by a large vibrating spike with conical end, is directed towards a support shoe 8 mounted to the end of the other jaw 4. The latter extends, beyond the articulation axis 5, by an arm 4a connected by a jack 9 to the jaw 3. This jack, with double effect, makes it possible to move aside or move closer the jaws 3 and 4 of the tool 1. The shoe 8 consists of a pair of side cheeks 8a, b articulated to the jaw 4, by means of a pair of pins 11, around an axis 10 parallel to the axis 5. These cheeks, which are connected together by a transverse plate 8c, end in two parallel rectilinear edges situated in a plane substantially perpendicular to the axis 12 of the tool 7 (the possibilities of pivoting of the shoe 8 with respect to the jaw 4 being limited for this purpose by abutment members not shown s) .It by these two edges 8 that the shoe bears against the wall 2, 8c plate being arranged set back, parallel to their plane; furthermore, a hole 13 is cut in the plate 8c around the axis 12, just as the end of the jaw 4 offers a hollow structure in the region of this axis.

 To use the demolition tool 1, it is brought, thanks to a lifting device to which it is suspended, above the wall 2 to be demolished, for example in reinforced concrete, and it is lowered, after having ordered a sufficient opening of its jaws 3, 4, so that the leading rod 7a of the rock breaker and the shoe 8 are placed on either side of the wall. Then the rock breaker is put into operation and the jaws are gradually tightened. The rod 7a, set in longitudinal vibration and acting like a hammer, the reaction forces being taken up by the shoe 8 which comes to lean against the other face of the wall, therefore penetrates into the concrete and pierces it from side to side.

Such an attack, repeated at successive points on the wall, creates a fracture line separating a piece of concrete 2a from the rest of the wall. It will be noted that the tightening of the jaws during each attack operation is only intended to apply to the pike of the rock breaker a sufficient pressure force so that it progresses satisfactorily in the masonry of the wall by effect of percussion; this pressure force alone would be inoperative without the rock breaker being put into action. Thanks to the fact that the shoe 8 and the end of the jaw 4 leave free an area surrounding the axis 12 of the rod. attack 7a of the tool, this can, at the end of penetration, come out without encountering an obstacle on the other side of the wall 2 and advance through the plate 8c and between the pins 11 of the shoe 8, while that the concrete debris detached from this side of the wall can be evacuated easily by the free space dO to the hollowed-out structure of the shoe and to the disposition of the plate 8c recessed with respect to the surface of the wall.

 The tool shown in Figure 1 is provided with a fastener 6 arranged so that, suspended by means of it, the rod 7a of its rock breaker 7 extends horizontally to the vertical to the part 6. As a variant, according to FIG. 3, the tool can be provided with a pair of attachment parts 6a, 6b fixed respectively in the central part of the jaws 3, 4. Suspended using these parts 6a, 6b by means of a lifting beam 60, the tool assumes a horizontal equilibrium position, its hinge axis 5 now being oriented vertically, which completely clears the space located above the breeze -rock 7 and allows to attack a vertical wall 2 to practice, parallel to a vertical edge 52 of the wall, a groove 50 not limited by the depth of the tool between jaws.

 Figure 4 shows another variant where the tool is provided with a single attachment part 6c, fixed in the central part of the jaw 3 so that the suspended tool has the rock breaker 7 oriented vertically, this which allows to attack and demolish a horizontal masonry wall 2.

 It will be noted that, if in the case of FIGS. 3 and 4 the jack 9 is arranged on the side opposite to that of the rock breaker 7, these two members are placed on the same side in FIG. 1. One or the other arrangement can be chosen according to the space requirements that the tool must respect both on the side of the breaker 7 and on the side of the shoe 8.

 As shown in FIGS. 5 and 6, the tool 1 in FIG. 1 can be used to demolish an uneven masonry wall or wall, namely the substantially cylindrical wall 2 of a factory chimney 40 of axis A. In this case, the tool 1 is suspended from a lifting device 15 carried by an annular scaffolding 16 surrounding the chimney, which is lowered along the latter as the progress of demolition work.

 The scaffolding 16 has a high floor 17 and a low floor 18 connected by an annular frame 19 (the structure of which is not specified in FIG. 5). The high floor 17 constitutes a work floor on which the attendant staff stands, inside a body guard 20. The scaffolding is supported by six links 46 hung on the top edge 23 of the chimney 40 and regularly distributed over its periphery. Each of them comprises a hydraulic jack 21 attached, by its body, to a point on the internal edge of the low floor 18 and, by its rod, to a clamp 22 placed on the top edge 23. By actuating the jacks 21, it is possible to modify the length of the links 46 and, consequently, to make the scaffolding 16 move vertically.

 The lifting device to which the tool 1 is suspended is a crane comprising a vertical mast 24 carried by the scaffolding, of which it crosses the top and bottom floors, and a horizontal boom 25 which can pivot around the axis of the mast 24 under the action of a hydraulic rack cylinder (not shown). A carriage 26, which a winch can move along the arrow 25, supports the tool 1 by means of a hook 27 and a cable 28 connected to a lifting winch 29. Through play displacement of the carriage 26 along the arrow 25 and the pivoting thereof around the mast 24, it is possible to bring the tool 1 above any point around the chimney and the '' descend there for the attack of the concrete veil 2.

 The scaffolding 16 also includes a console 30 for controlling the various hydraulic or electrical members of the installation (jacks, winches, rock breaker) as well as a hydraulic unit 31 arranged on the low floor 18. Under the latter are fixed guide rollers 32 preventing friction between the scaffolding and the chimney.

 At the start of the demolition of the chimney 40, the scaffolding 16 is installed, as will be explained below, at the top of the chimney 40 to which it is hung using the clamps 22 adjusted to the thickness of the web 2, by means of the jacks 21 placed in almost complete extension.

Using the desk 30, a worker, standing on the work floor 17, controls the crane 15 so as to bring the tool 1 vertically to a point on the top edge 23 of the chimney, then to put it into action while gradually lowering it to a height h (as large as the depth of the tool allows), then moving it over a certain horizontal length parallel to edge 23, then raising it above said edge . A first U-shaped cut is thus made at the top of the chimney, while a second worker monitors the fracturing of the reinforced concrete wall, cuts the reinforcing bars with shears and drops them inside. the chimney the wall panel thus detached. Then other panels are successively cut along invoice lines in L and eliminated in the same way. When the attacked panel 2a carries a clamp 22 used for the suspension of the scaffolding 16 (FIG. 6), this clamp joint is removed beforehand, after putting the corresponding jack 21 to rest, as shown in the right part of FIG. 5, while the scaffolding remains sufficiently supported by the five other jacks 21 and their clamps 22.

Then, after elimination of the panel, the clamp is replaced on the new top edge 23a, located at a lower level of the abovementioned cutting height h, and the corresponding jack 21 is reactivated, with a retracted elongation of the height h so that the corresponding link 46 resumes its share of the support of the scaffolding 16.

 The top of the chimney is thus attacked and demolished by the tool 1 moved, using the crane 15, over its entire periphery, including in the region of the mast 24 thereof where, despite the free space reduced, its jaw 4 can easily be inserted because the jack 9 is arranged on the side of the other jaw 3.

 When a crown of height h has thus been eliminated by panels, the scaffolding 16 is suspended via the six jacks 21 in the retracted position. Then, by controlling the progressive deployment of the six jacks, the scaffolding is slowly lowered from the height h, which is thus brought into position to allow the demolition of a new wall crown of height h. One proceeds successively in this way to the bottom of the chimney 40.

 Prior to the actual demolition operations, scaffolding 16 must be hoisted to the top of the chimney.

To do this, it is first of all placed on the ground, at the foot of the chimney (FIG. 7), and to the rod of each of the jacks 21 is attached a long cable 35 which is passed over the 'one of six pulleys 36 that we went to climb to the top of the chimney, directly above the jacks 21. Each cable 35 then descends to the scaffolding where it is introduced into a traction device 37 fixed to the scaffolding in the vicinity of the corresponding jack 21. These traction devices, called "Tirfor", are capable of absorbing and blocking under mechanical tension a cable which they receive, in the manner of a winch.

 After installing this equipment, all the jacks 21 having been initially extended, three of these six jacks are made to contract, the left jack in FIG. 7 being one of the three jacks in question. This results in a rise in the scaffolding 16 (FIG. 8), while the slack taken up by the cables 35 attached to the other jacks is absorbed by the corresponding traction devices 37, of which is the one which appears to the right of the chimney. Then the first three jacks are extended again, the slack that their cables 35 then take up being absorbed by the corresponding traction devices 37, so that the jacks 21 are all six in extension (FIG. 9) to support the scaffolding 16 who left the ground. These operations are repeated so as to raise the scaffolding step by step to the top of the chimney.

 The scaffolding 16 is hoisted after being fitted with the mast 24 of the crane 15, fixed by keying. The rest of the components of the crane are subsequently mounted, after the scaffolding arrives at the top of the chimney, using an auxiliary lifting device (not shown) carried by the scaffolding.

 When it comes to demolishing a non-cylindrical chimney, that is to say of variable diameter, for example a frustoconical chimney, an expandable annular scaffolding as shown in FIG. 10 is used. The frame of this scaffolding is consists of six cages 38 which offer an angled shape covering a circular sector in plan and are limited by end faces 38a, b forming an angle of about 600 between them. These six cages, arranged in a ring and provided respectively with the six abovementioned jacks 21, are connected to each other by compasses each formed from two panels 39 hinged together and to the end faces of the cages 38 contiguous along three axes of articulation parallel to the axis of the ring formed by the scaffolding which, in use, coincides with the axis A of the chimney 40. In addition, these end faces 38a, b are kept parallel to one another, with adjustable spacing, by a screw jack 41 whose screw, with double thread ge in the opposite direction, can be actuated in rotation using an operating mandrel 42 wedged in its middle so as to control the bringing together or the spacing of the end faces 38a, b by means of nuts 43a, b which are respectively integral with these and in which engage the parts with reverse threads of the screw. The work floor 17 is here composed of panels 44 covering the cages 38 and of the same shape in plan as these, and of panels 45, of rectangular shape, covering the intervals between cages where the link compasses are located and resting on the ends of the adjacent panels 44 with mutual sliding when adjusting the screw jacks 41.

Claims (12)

Claims  1. Wall demolition tool, in particular in reinforced concrete, comprising a pair of articulated jaws provided with a means for controlling the spacing of their ends, which carry opposing mounted attack members which are brought together and on the other side of a wall to be demolished by straddling it by the pair of jaws, characterized in that the aforementioned attack members consist firstly of a rock breaker (7) mounted on the '' one (3) of the jaws, its perforating spike (7a) being directed towards the end of the other jaw (4), and on the other hand by a support shoe (8) mounted on the latter, facing said perforating spike, and that the conformation of the support shoe (8) and of the means for connecting the latter to the jaw which carries it is such that, when the jaws (3, 4) close, the perforating spike ( 7a) can pass through the shoe without encountering an obstacle.  2. Tool according to claim 1, characterized in that at least one of its jaws is provided with attachment means (6; 6a, 6b; 6c) for suspending it from the cable of a lifting device.  3. A method of demolishing a tubular masonry veil with a vertical axis, in particular in reinforced concrete, such as a chimney, making use of the tool according to claim 1 or 2, characterized in that it consists of install around the top of the tubular web (2) an annular scaffolding (16) carrying a crane (15) to the boom of which hangs the demolition tool (1), to attack and demolish by successive panels (2a), using the latter, the top part of the tubular veil over the extent of a crown of determined height (h), to lower the scaffolding (16) by an amount equal to this height, to attack and demolish in the same way the new top part on said height, and so on step by step until the foot of the tubular veil.  4. Method according to claim 3, characterized in that the scaffolding (16) is supported by suspension, using links (46) of variable length on order, at the top edge (23, 23a) of the web ( 2) either initial, or born from the demolition of the part of the veil which surmounted it.  5. Method according to claim 4, characterized in that links (46), hooked to said top edge (23), are unhooked in turn to allow the demolition of a panel (2a) of sail where they were respectively hung, each of them then being hung up on the new top edge (23a) resulting from the demolition of said panel, after which a reduction in the length of the corresponding link (46) is ordered so as to restore it to its function of scaffolding support (16).  6. Method according to claim 4 or 5, characterized in that each step of descent of the scaffolding (16) is achieved by controlling an identical elongation for each of the links (46) which support it.  7. Method according to any one of claims 3 to 6, characterized in that the scaffolding (16) is previously hoisted to the top of the tubular veil (2) using a set of flexible links (35, 21) of variable length on command, each of which is attached by one end to the scaffolding at one of several points distributed around the periphery thereof, goes up to pass on a stationary pulley (36) installed at the top of the sail, then descends to attach to the scaffolding at a point close to the aforementioned point, by alternately ordering a reduction in the length of some of these links, then re-tensioning of the other links.  8. Equipment making it possible to implement the method according to any one of claims 3 to 7, characterized in that it comprises  - an annular scaffolding (16),  - A set of links (46) supporting the scaffolding by suspension at the top edge (23, 23a) of the tubular web (2), these links, each of which is of adjustable length on command and can be hung on said edge or in be detached, being distributed over the periphery of the scaffolding (16) in sufficient number so that any of them can be detached without compromising the stability of the scaffolding suspended by the other links (46), and  - A crane (15) carried by the scaffolding, to the boom (25) from which the demolition tool (1) is suspended, this crane being designed to allow the supply of the rock breaker (7) of this tool at any point of a top part of the tubular veil (2) extending over a crown of determined height (h).  9. Equipment according to claim 8, characterized in that each link (46) includes a jack (21) making it possible to vary the length thereof and a member (22) for temporary attachment to said top edge (23, 23a) , the link being attached to the scaffolding via the jack.  10. Equipment according to claim 9, characterized in that the scaffolding (16) is fixed, near each cylinder (21), a traction device (37) acting as a winch, by which can be attached to the scaffold a cable (35) for hoisting it, this cable, after passing over a pulley (36) mounted at the top of the web (2), returning to attach to the scaffold via of said cylinder.  11. Equipment according to any one of claims 8 to 10, characterized in that the scaffolding (16) is radially expandable.  12. Equipment according to claim 11, characterized in that the scaffolding (16) is formed by several sectors (38) assembled in a ring by means of connecting elements (39, 41) of adjustable length.