Classifications

• • E—FIXED CONSTRUCTIONS
  • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
  • E02B—HYDRAULIC ENGINEERING
  • E02B3/00—Engineering works in connection with control or use of streams, rivers, coasts, or other marine sites; Sealings or joints for engineering works in general
  • E02B3/04—Structures or apparatus for, or methods of, protecting banks, coasts, or harbours
  • E02B3/12—Revetment of banks, dams, watercourses, or the like, e.g. the sea-floor
  • E02B3/129—Polyhedrons, tetrapods or similar bodies, whether or not threaded on strings

Definitions

• the invention relates to a maritime or fluvial hydraulic structure comprising a shell, such as a pier, a spur, an underwater reef, a detached breakwater, a solid breakwater and coastal road, a dike. river, or a bank protection structure.
• a shell such as a pier, a spur, an underwater reef, a detached breakwater, a solid breakwater and coastal road, a dike. river, or a bank protection structure.
• These blocks which comprise a central part with a solid core and projecting legs of this central part, have a geometry resulting from a compromise between robustness and hydraulic stability so as to withstand, for example, shocks and mechanical forces due to the swell. and the waves.
• the artificial blocks used until now can have dimensions of several meters in height and laterally (dimensions that can be modified according to the application and the conditions of use referred to) and generally include massive parts made by concrete formwork.
• An object of the invention is to provide the sector of the realization of maritime and river protection works a new type of shell, having a spatial modulation of its porosity.
• Another object of the invention is the use of rockfill blocks that can be made with highly reactive cements with improved reliability.
• the subject of the invention is a hydraulic structure comprising a shell formed of interlocking stone blocks interlocking into each other, in which the rockfill concrete blocks comprise a central part with a solid core and legs which protrude from this central portion, wherein the blocks comprise at least one duct extending radially from the inside of the core of the central portion and opening on the outside of the block, wherein the shell has a Heterogeneous permeability, the shell being formed of first blocks having a first porosity, defined by a first number of conduits and / or by first duct dimensions specific to the first blocks, and at least second blocks having a second porosity, different from the first porosity and defined by a second number of ducts and / or second duct dimensions specific to the second blocks, the number of channels; second blocks being different from the number of channels of the first blocks and / or the dimensions of the channels of the second blocks being different from the dimensions of the channels of the first blocks.
• the ducts in the blocks forming the shell it is possible to vary the porosity (permeability) of the shell of the hydraulic structure such as a coastal or river protection structure, not by varying the size of the concrete blocks constituting the carapace, but by varying the intrinsic porosity of these blocks by variations in the dimensions of the ducts and / or the number of these ducts in these blocks.
• the shell may further comprise third blocks having a third porosity, defined by a third number of ducts and / or third duct dimensions specific to the third blocks, the first blocks, the second blocks and the third blocks which may be situated respectively in a lower part, in a median part and in an upper part of the shell, the median part being able to be located above the lower part and below the upper part, the first blocks and the third blocks may have porosities higher than the second blocks;
• the first blocks may be situated in a first longitudinal portion of the structure and the second blocks may be located in a second longitudinal portion of the structure, the second blocks may have a greater porosity higher than the first blocks;
• said duct may be part of a through passage
• said blocks may each comprise a plurality of ducts with at least one duct ending in a cul-de-sac;
• the core is substantially cubic shape and has two opposite end faces and two opposite side faces
• the legs may comprise two front lugs projecting from the central portion respectively perpendicular to the two front faces of the core and two lateral lugs projecting from the central portion respectively perpendicular to the two lateral faces
• each block may comprise at least one duct which extends radially from the inside of the core of the central portion and which opens on the outside of the block between a front leg and an adjacent side leg;
• each block may furthermore comprise at least one through conduit which passes through the core and which opens at ends of the front tabs;
• each block may furthermore comprise an internal cavity located in the central part and in which the conduit opens out;
• said through passage may have an upward orientation, so as to facilitate the circulation of a fluid by convection through the block in which it is included when the block rests on the ground;
• the blocks may further comprise each of the additional conduits respectively in the tabs, to allow the circulation of a fluid in the corresponding tab to promote the evacuation of hydration heat generated by the concrete during the manufacture of said blocks;
• the ducts may allow a circulation of a fluid in the core to promote the evacuation of hydration heat generated by the concrete during the manufacture of said blocks.
• conduits and the possibility of doing to vary their number and / or their dimensions, offers the possibility of designing a shell of blocks that can be of the same geometry and size, but of different porosities to adapt these blocks to the specific needs and / or functions of different parts of said shell.
• Another advantage of the blocks used is related to the heat of hydration generated during the formation of concrete blocks.
• the heat of hydration can cause two phenomena that can damage the blocks structurally.
• the first is related to thermal gradients induced by the heat of hydration, which cause differential expansion in the block and consequently induce significant stresses and cracks.
• the second is related to the creation of deleterious secondary chemical compounds within the concrete, such as secondary etangement, affecting the durability of the blocks.
• the secondary étingite spreads over time, especially in humid environments, which can induce a deterioration of the concrete of the interior which can go as far as the destruction of the structure formed by the concrete.
• An openwork concrete block for rip rap used in the hydraulic structure according to the invention comprises one or more ducts, open or non-through, through which a natural and / or forced ventilation limits the temperature rise induced by the heat of hydration during the formation of the block, which removes or limits the degradation phenomena of the blocks detailed above.
• the presence of such conduits makes it possible to better use the quantity of concrete necessary for the manufacture of the block by distributing it differently on the latter, which makes it possible to redistribute the volume of concrete equivalent to the volume of the ducts situated in the central part of the block. block to increase all the external volume of the latter.
• the perforated block takes up more space in the structure and thus reduces the number of blocks and the amount of concrete for the whole of a riprap.
• FIG. 1A represents a tetrahedron
• Fig. 1B shows a conventional block based on the geometry of the tetrahedron
• Figure IC represents a block according to the invention based on the block of FIG.
• Figure 1D shows a detail of the block according to the invention of Figure IC;
• FIG. 2A represents a perspective view of a block according to the invention
• Figure 2B shows the core of the block of Figure 2A;
• Fig. 3A shows a front view of the block of Fig. 2A
• Fig. 3B shows a section C-C 'of the block of Fig. 2A;
• Figs. 4A and 4B show, respectively, sections B-B 'and A-A' of the block of Fig. 2A;
• Figures 5A1 and 5A2 show a cross section and a top view of a dike, respectively;
• Figs. 5B1 and 5C1 show, respectively, a horizontal section and a vertical cross section of the dike of Figs. 5A1 and 5A2 showing a conventional dike carapace structure
• Figs. 5B2 and 5C2 show, respectively, a horizontal section and a transverse vertical cross section of the dike of Figs. 5A1 and 5A2 showing a dike shell structure taking advantage of a variation in block porosity
• Figure 6 shows a section B-B 'of a variant of the block of Figure 2A.
• a concrete block for rip rap can be formed of a core of which legs project in a three-dimensional geometry.
• the tabs have a hooking role for mutual nesting between adjacent blocks and the core has the role of securing the tabs of a block to each other.
• Blocks consisting of legs projecting from a core instead of massive blocks can limit the consumption of concrete and, possibly, to obtain a better dispersion of wave energy.
• a structure of given dimensions requires a quantity of concrete depending on the porosity of the material (here, an assembly of blocks) constituting it, porosity itself a function of the geometry of the blocks.
• the tetrahedron is one of the simplest three-dimensional geometric shapes.
• a tetrahedron 10 has four vertices S1, S2, S3 and S4 defining triangular facets and has a center of gravity G.
• FIG. 1B illustrates a conventional block having a geometry based on a tetrahedron: a central part PC of the block comprises a solid core 12 in which is located the center of gravity G of the tetrahedron.
• the legs are in contact at zones 15 of birth of the legs. This geometry is known from US Pat. No. 2,766,592.
• the core 12 is by nature the most compact part of the block, and therefore the one that is most concerned by the problems caused by the heat of hydration generated during the setting phase of the concrete during the formation of the block.
• a block according to the invention comprises conduits intended to facilitate the evacuation of the heat of hydration.
• conduits In the conduits, a natural or forced circulation of a fluid between the core and the outside of the block can take place, thus allowing the removal of the heat of hydration and the limitation of the rise in temperature of the block.
• the fluid may be the surrounding air or a coolant, such as water.
• Fluid circulation may be forced by means such as fans or a pumped water circulation system.
• the ducts do not significantly compromise the mechanical integrity of the block.
• Ducts ending in cul-de-sac allow direct access to the volumes of concrete to be cooled and can promote the maintenance of the mechanical robustness of the block compared to a similar block having conduits connected to each other.
• connected conduits may form one or more through-passages, for example by extending to the center of gravity of the block, inside the core, to facilitate the circulation of the fluid and promote the evacuation of the heat of hydration.
• FIGS. 1C and 1D illustrate the application of the invention to the block of FIG. 1B.
• a block 100 according to the invention can be based on the conventional block 11 of FIG. 1B and comprise ducts 20 and 30 that can join within the core, and / or tabs 30 '. ending in cul-de-sac.
• Figure 1D shows a section of a lug 14 of the block 100 comprising ducts 40 joining and ducts 40 'dead-end.
• the ducts 20 are located along the extension directions of the tabs and open at the ends thereof.
• the ducts 30 and 30 ' open out between two adjacent tabs in zones 15.
• the ducts 20 can simultaneously cool the legs and the core, but they can be difficult to achieve the length and width of the legs.
• the ducts 30 and 30 are more efficient for cooling the core and easier to perform, but they do not allow the cooling of the legs.
• An advantage of the interconnection of all or part of the conduits 20, 30 and 40 is the creation of passages P 'allowing easy circulation of a fluid through the block.
• the block 100 can rest stably on a horizontal plane ground on its three support points SP1, SP2 and SP3.
• One or more of the ducts may end in cul-de-sac, such as ducts 30 'and 40', instead of forming passages P such as ducts 20, 30 and 40.
• the section of a conduit may be constant along its extension direction.
• the geometry or geometries of the ducts, their number and their dimensions must be adapted according to the priorities of the project concerned, for example the robustness of the block, its longevity, the production speed of the blocks, the savings in concrete or the reconquest of the site by targeted animal species.
• FIGS. 2A to 4B and 6 illustrate the case of a block 200 according to the invention based on that described in patent FR 2 791 370.
• the block has three planes of symmetry, xoz, xoy, and yoz, respectively corresponding to sectional planes A-A ', B-B' and C-C '.
• the cutting plane AA ' is normal to the view planes of FIGS. 3A, 3B and 4A
• the section plane BB' is normal to the view planes of FIGS. 3A, 3B and 4B
• the section plane CC ' is normal to shots of Figures 4A and 4B.
• the shape of the block 200 can be described as being established around a central part PC with a solid core 201, represented by FIG. 2B in the same orientation as FIG. 2A, of cubic shape, having a first front face 110 and a second rear face 120 opposed to each other, a third lower face 130 and a fourth high face 140 opposite one another, and a fifth left side face 150 and a sixth opposite side face 160 opposite each other. one to the other.
• the first and second faces 110 and 120 of the core are each provided with a front lug 310 protruding perpendicularly to these faces.
• Each front lug 310 has a generally truncated pyramid shape having four substantially identical lateral faces 312 and a front face 314 parallel to the faces 110 and 120 of the core.
• each front lug 310 The four lateral faces 312 of each front lug 310 are each extended by an enlargement facet 315 contiguous to widening facets 215 of the lateral lugs to increase the robustness of the block.
• the facets of enlargements are localized in zones of birth of the legs.
• Each of the third and fourth faces 130 and 140 serves to support an anvil-shaped side tab 210.
• the two lateral tabs 210 protrude perpendicularly from the two opposite faces 130 and 140 of the core, each of these two lateral tabs extending in two opposite lateral directions, left and right, parallel to the two opposite faces 130 and 140 and perpendicular to the directions of extension of the two front legs 310; these two lateral tabs 210 each comprise a table 212 parallel to the faces 130 and 140 of the core 100, two end faces 214 opposite and parallel in pairs to the faces 110 and 120 of the core, and may extend to cover the lateral faces opposites 150 and 160 of the core.
• Each side tab 210 has a general anvil shape having a transverse indentation 216 extending over the entire width of the table separating it into two portions.
• the end faces 214 of the lateral tabs 210 and the end faces 314 of the front tabs 310 may have a rough surface formed by pyramidal protuberances 400, which may contribute to strengthening the blocking ability of the block.
• the pyramidal protuberances 400 of the end faces 214 are not shown in FIGS. 4A and 4B.
• corner edges of the side and front legs are folded and form chamfers.
• the block comprises four ducts 610 and four ducts 620 joining in the core and opening each in one of the enlargement facets 315 of the front tabs 310, that is, opening into the birth zones of the tabs, between one of the front tabs and one of the lateral tabs; two ducts 630 joining and joining the ducts 610 and 620 in the core and opening each into the front face 314 of one of the two front lugs 310, forming a through duct which passes through the core and which opens at the ends of the front legs 310; and eight ducts 640 forming two by two four passages between the front and rear sides of the block at the end faces 214 of the side tabs 210.
• an effective ventilation of the core by convection can take place through the passages P and P 'formed by the ducts 610, 620 and 630 which meet in its interior.
• each side tab 210 can be used for laying the block on a flat and horizontal floor, parallel to the xoy plane of Figure 2A, for storage before use.
• the ducts 610 form upwardly directed passages and are particularly effective for cooling the core of the convective block.
• Block 200 may be characterized by the following dimensions as shown in FIGS. 3A-4D.
• the side tabs 210 may be characterized by widths (210) of 0.26, 11 (210) of 0.29, 12 (210) of 0.34, 13 (210) of 0.27, 14 (210). of 0.34, and with heights h1 (210) of 0.17, h2 (210) of 0.28, h3 (210) of 0.01 and h4 (210) of 0.01 and h5 (210) of 0.01; the front legs 310 may be characterized by widths (310) of 0.23, 11 (310) of 0.25, 12 (310) of 0.33, 13 (310) of 0.51 and 14 (310).
• the pyramidal protuberances 400 may be characterized by a base width 1 (400) of 0.01 and a height h (400) of 0.003.
• conduits 610, 620, 630 and 640 have, respectively, diameters 0 at the outside surfaces of the block between 0.05 and 0.10 for 0 (610), between 0.6 and 0.12 for 0 (620) and between 0.04 and 0.08 for 0 (630) .
• the upper limits of the diameters of the ducts indicated above correspond to a compromise in which the cooling capacities of the ducts are maximum without a significant reduction in the robustness of the block.
• these upper limits may be exceeded if, depending on the intended application, it is acceptable to modify the geometry of the block 200 to redistribute the structural volumes of this block, for example with the aim of increasing the porosity of the block, the latter corresponding to the volume of the openings formed in the block relative to the external volume of the block; increasing the number of ducts and / or their dimensions, and therefore their volumes, increases the porosity of the block, zero for a total absence of openings therein.
• the porosity of the block can also be increased by forming an internal cavity Cav, located in the core and in which the ducts open, as shown in FIG.
• This internal cavity can have a characteristic dimension l Ca v greater than the diameters of the ducts, and has the advantages of resulting in a lower consumption of concrete, a reduction of heat emission of hydration at the core and a better evacuation of it.
• the presence of the conduits in a rockfill concrete block according to the invention allows to easily modulate the porosity or permeability of a structure consisting of such blocks considered as a whole so that it has a heterogeneous porosity.
• Hydraulic protection structures comprising sets of identical blocks positioned next to each other in a homogeneous matrix, such as for example the breakwaters described in the patent application US 2015/0050086.
• FIGS. 5A1 and 5A2 represent, respectively, a transverse section and a view from above of a coastal protection structure 500 constituted by a dike comprising, below a cap 510 surmounting a slope 502 placed on a ground 503 , a carapace 520 inclined and made of blocks for rip rap that covers and protects the slope from external aggression; these blocks can be dimensioned differently in different longitudinal portions of the shell in order to meet the robustness requirements of these different portions while limiting oversizing.
• a first longitudinal portion 504 and a second longitudinal portion 506 of the shell 520 may consist of blocks of the same shape but different dimensions and weights, for example blocks of 6 m 3 for part 504 and blocks of 4 m 3 for part 506.
• FIG. 5B1 which shows a horizontal section X1-Y1 of the carapace, passing directly from blocks 522 4 identical to each other in the longitudinal portion 504 to 522e blocks identical to each other in the longitudinal portion 506, which naturally leads to using oversized blocks on at least a portion of the shell of the portion 504 along the limit Ll: in the example taken here, blocks of 6 m 3 are used on part of the carapace where it is might be acceptable to use smaller and / or lighter blocks.
• blocks 525 according to the invention whose porosities are different depending on the positions of the blocks in the horizontal section Xl-Yl, c that is, at a given vertical position in the carapace.
• the blocks 525 4b having a higher porosity than the blocks 525. 4a but may be of the same external shape and have the same external dimensions as these, so that the longitudinal portion 504 comprises two longitudinal portions 504 'and 504 "as shown in Figure 5B2, the blocks of the longitudinal portion 504" having a higher porosity than the blocks of the longitudinal portion 504 '.
• This band of relatively high porosity blocks allows both a saving in concrete and an improvement in the behavior of the dike by reinforcing its capacities directly related to the porosity such as the wave energy dispersion and resistance to wave crossing; moreover, its constitution does not necessarily entail additional difficulties in the placement of the blocks since they can all have the same external shape and the same external dimensions for the same portion longitudinal.
• the blocks 522 4 are conventionally all sized to withstand stresses actually experienced only by a median portion PM of the carapace, located below of a high part PH and above a low part PB as illustrated by figure 5C1, the middle part undergoing the most important waves forces
• the blocks are identical over the entire height of the carapace, oversized in relation to the weight requirements and robustness in the lower part and in the upper part of the carapace.
• blocks according to the invention with different porosities according to their vertical positions in the shell, as illustrated by FIG. 5C2, makes it possible to produce a shell having characteristics that can be modulated in the vertical direction by using blocks 525 of the same external geometry and of the same external dimensions, the bottom PB of the shell being made up of blocks 525 b having a first porosity, the middle portion MP of blocks 525 m having a second porosity and high PH of blocks 525 h having a third porosity, the first and third porosities being preferably higher than the second porosity.
• a high porosity of the blocks 525 b at the bottom PB encourages ecological conquest blocks by sub-marine animal species;
• a low porosity of the 525 m blocks in the middle part PM promotes the robustness of the blocks to withstand the strong mechanical stress imposed by the swell at this level of the structure as well as a high weight to withstand the thrust of the swell;
• a high porosity of the 525 h blocks in the upper part PH improves the dispersion of the wave energy and limits the crossing of the structure by the waves.
• a carapace having only two of these three low, middle and high parts, for example a carapace comprising only the lower and middle parts or the middle and high parts.
• a structure coastal protection system 500 comprising a shell formed of concrete blocks and characterized in that, at a given vertical positioning in the shell, the blocks have a higher porosity in a first longitudinal portion 504 "of the structure than in a second longitudinal portion 504 'of the structure, and / or, in a given longitudinal portion of the shell, the blocks have a higher porosity in a lower part PB and in an upper part PH than in a middle part PM situated above of the lower part and below the upper part, as described in Figures 5A1 to 5C2 and the corresponding text.
• a block 525 4a and a block 525 m can have a porosity of zero, equal to or less than 2%, 5%, 10% or 30%; a block 525 4b may have a porosity at least greater than 2 percentage points, 5 percentage points, 10 percentage points, or 20 percentage points to the porosity of block 525 4a ; a block 525 b and / or 525 h block can have independently of porosities at least greater than 2 percentage points, 5 percentage points, 10 percentage points to 20 percentage points to the porosity of a block 525 m.
• blocks 525 of the same type, according to the invention including the number and the sizes of the ducts, and therefore the porosity and weight vary, without causing particular difficulty in the implementation of these blocks since their external dimensions may be the same.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Inorganic Chemistry (AREA)
• Environmental & Geological Engineering (AREA)
• Ocean & Marine Engineering (AREA)
• Mechanical Engineering (AREA)
• Civil Engineering (AREA)
• Structural Engineering (AREA)
• Revetment (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=63209472

Family Applications (1)

Country Status (5)

Citations (10)

Family Cites Families (1)

• 2018
  • 2018-03-19 FR FR1852335A patent/FR3078984B1/fr not_active Expired - Fee Related
• 2019
  • 2019-03-18 WO PCT/FR2019/050602 patent/WO2019180359A1/fr unknown
  • 2019-03-18 EP EP19717542.5A patent/EP3768897B1/fr active Active
  • 2019-03-18 ES ES19717542T patent/ES2912890T3/es active Active
  • 2019-03-18 PT PT197175425T patent/PT3768897T/pt unknown

Patent Citations (10)

Also Published As

Similar Documents

Legal Events