Abstract:
A fire-resistant road-system apparatus includes at least one cover can be arranged detachably in a frame that is intended to be fixed to the ground, to close a gallery or an underground technical room to protect it from fires. A casing filled with a heat-insulating refractory material is fixed detachably under the cover. The invention is applied in road-system or railroad tunnels.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to road-system fire stop equipment comprising at least one cover or plug, which can be arranged detachably in a frame intended to be fixed to the soil, to close off a gallery or an underground technical room which has to be protected from fires.  
         [0002]     It applies to the type of road-system equipment which is installed, for example, in road-system or railroad tunnels, and subject to drastic safety standards, requiring that the technical equipment housed in the underground rooms that are closed off by road-system equipment must be effectively protected by this equipment for a predetermined period in case of a fire in the tunnel.  
       BACKGROUND  
       [0003]     Road-system equipment is known that protects the technical equipment housed in the underground room, which is closed off by the covers or plugs of the equipment, and consists in providing one or more covers comprising a heat-insulating material arranged on top of each cover, or a plug, arranged in the support frame that is secured in the ground.  
         [0004]     This known arrangement has the drawbacks of having a very complex and consequently expensive structure, and of being difficult to install, since subcovers must be available in the technical room before closing the latter with external covers or plugs. In addition, access to the technical equipment housed in the room is not easy, because the external covers or plugs have to be removed first so that then one can reach the subcovers and remove them from the room.  
       SUMMARY OF THE INVENTION  
       [0005]     The purpose of the present invention is to eliminate the above drawbacks of known fire-resistant road-system equipment.  
         [0006]     For this purpose, the invention proposes road-system fire stop equipment comprising at least one cover or plug, which can be arranged detachably in a frame intended to be secured to the ground to close off a gallery or an underground technical room which is to be protected from fires, and characterized in that it comprises a casing that is filled with a heat-insulating refractory material and is fixed detachably under the cover.  
         [0007]     The equipment comprises at least a second cover, which can be arranged so it rests on the frame in alignment and in the same plane as the first cover, and a second casing, which is filled with a heat-insulating refractory material and fixed detachably under the second cover.  
         [0008]     Each cover is in the form of an inverted basin which is filled with a heat-insulating refractory material, and whose external upper wall is provided with continuous passages which are also filled with the refractory material and just come in contact with the external face of the wall of the cover.  
         [0009]     The external upper wall of each basin of the cover is surrounded by a gutter, which is delimited by the external walls of the cover and raised parallel to perforated lateral walls of the basin opposite the walls where the refractory material fills the peripheral gutter through the holes of the lateral walls of the basin.  
         [0010]     The external walls of each cover and the bottom wall of the peripheral gutter constitute the seat of the cover and they can come to rest with their external faces respectively on the internal faces of the lateral walls of the frame, delimiting its opening and an internal peripheral ledge integrally connected to the lateral walls of this frame.  
         [0011]     Each cover comprises lower peripheral walls that extend under the bottom wall of the peripheral gutter to delimit the inverted basin of the cover, where these lower peripheral walls are at a separation from the lateral walls of the frame when the cover is arranged so that it rests in the frame.  
         [0012]     It is preferred for each casing or bottom, in the form of a box containing the heat-insulating refractory material, to be fixed detachably under the corresponding cover so that the end borders of the lower walls of The basin rest on the refractory material of the casing, and the free upper parts of the walls of the casing surround, with some separation, the lower walls of the basin when the cover is arranged in its frame.  
         [0013]     Several threaded rods are anchored by their respective heads to the wall of the corresponding cover, perpendicularly under the latter wall, opposite, respectively, continuous passages in the wall of the cover so that the heads of these threaded rods are embedded in the refractory material filling these passages, and so that the threaded rods are partially embedded in the refractory material filling the basin of the cover, protruding outside this material opposite the wall of the cover where the casing is fixed under the cover by threaded rods that traverse the refractory material of the casing, and where the lower wall forms the bottom of the casing, and is screwed by nuts to the threaded rods on the bottom wall of the casing.  
         [0014]     The head of each threaded rod is anchored in a contact plate that is integrally connected to the internal face of the wall of the cover opposite the corresponding continuous passage of this wall.  
         [0015]     The second cover presents a structure with an inverted basin which is filled with a heat-insulating refractory material that is substantially identical to that of the first cover, * where the external upper wall of the second cover has one of its edges, which is not bordered i by a gutter, such that it can be rest directly on the corresponding raised external wall of the first cover when the two covers are arranged in the frame, and the second cover comprises, under the border of its upper wall that rests on the external wall of the first cover, a bar arranged with clearance below the corresponding bottom wall of the gutter of the first cover, by being opposite, with some separation, the corresponding lower wall of the basin of the first cover.  
         [0016]     According to another embodiment, each cover is in the form of a basin filled with a heat-insulating refractory material and comprises a peripheral ledge constituting the seat of the cover and delimiting the basin of the cover into two parts, an upper and a lower part, having a larger and smaller cross section, respectively, and the cover rests with its peripheral ledge on an integrally connected internal peripheral ledge of the lateral walls of the frame, so that the lateral walls of the upper part of the basin rest on the internal faces of the lateral walls of the frame, and the lateral walls of the lower part of the basin are separated from the lateral walls of the frame.  
         [0017]     Each casing containing the heat-insulating refractory material is fixed detachably under the corresponding cover of this other embodiment, so that the bottom wall of the basin rests on the refractory material of the casing, and the free upper parts of the walls of the casing surround, with some separation, the lower part of the basin when the cover is arranged in its frame.  
         [0018]     Several threaded rods with heads traverse the bottom wall of the basin, protruding perpendicularly under this wall, where the heads of these rods rest on the internal face of the bottom wall of the basin and are embedded in the refractory material that fills the basin, and the casing is fixed under the cover by the threaded rods that traverse the refractory material of the casing and the bottom wall of the casing, and by nuts that are screwed to the threaded rods under the bottom wall of the casing.  
         [0019]     The second cover of this other embodiment has one of its lateral walls, which does not comprise a peripheral ledge part, present an upper part that can be placed directly on the upper part of the corresponding wall of the first cover when the two covers are arranged in the frame, and the second cover, which is integrally connected to its lateral wall, comprises a bar arranged with clearance below the corresponding ledge of the support wall of the first cover, by being opposite, with some separation, the lower part of this support wall.  
         [0020]     Advantageously, a heat-expandable joint is interposed between the bar of the second cover and the bottom wall of the gutter of the first cover or the ledge of the first cover.  
         [0021]     The casing with refractory material, which is fixed under the second cover identically to the casing of the first cover, extends in the same plane as the casing of the first cover, and one of its lateral walls faces, with some separation, the corresponding lateral wall of the casing of the first cover when these covers are arranged in the frame.  
         [0022]     A part forming a joint with the heat-insulating refractory material is fixed to at least one of the bottom walls of the casings of the two covers, so that it covers the space between the two lateral walls opposite the two casings perpendicularly to this space.  
         [0023]     Advantageously, the part forming the joint consists of a flat parallelepiped box covering the two bottom walls of the casings of the two covers, perpendicularly to the plane of the above-mentioned space, and containing the refractory material that can consist of refractory concrete, or of one or more noncombustible heat-insulating superposed plates based on calcium silicate and alumina.  
         [0024]     The lateral walls of each cover casing are separated from the lateral walls opposite the frame, and the bottom wall of each cover casing hangs over a lower peripheral ledge of the lateral walls of the frame, where a heat-expandable peripheral joint is interposed between this ledge and the bottom wall of the casing.  
         [0025]     Advantageously, the frame presents a modular structure with main beams and crosspieces which can be assembled detachably to each other to receive several juxtaposed covers.  
         [0026]     The lateral walls of the frame are perforated and a heat-insulating refractory material fills the openings of these walls before embedding the frame in the ground.  
         [0027]     The refractory material that fills the basin of each cover is, for example, concrete cast into the basin in at least two layers that can present heat and mechanical resistance properties that differ from one layer to the other, and the material filling the openings of the main beam and crosspieces of the frame is also concrete cast into these openings.  
         [0028]     The material that fills each cover casing consists of concrete or one or more heat-insulating noncombustible superposed plates based on calcium silicate and alumina.  
         [0029]     The continuous passages are in the form of oblong holes distributed over the main portion of the surface of the upper wall of each cover.  
         [0030]     Each cover is rectangular in shape.  
         [0031]     Each casing can be replaced by another casing having a different height from that of the preceding one, and can be fixed detachably under the corresponding cover being filled with a heat-insulating refractory material. 
     
    
     BRIEF DESCRIPTION OF DRAWING FIGURES  
       [0032]     The invention will be understood better, and other purposes, characteristics, details and advantages of the invention will become clearer in the following explanatory description, which is made in reference to the drawings in the appendix that are given only as an example illustrating two embodiments of the invention, in which drawings:  
         [0033]      FIG. 1  is a lower half-view with transverse cross section of a railroad tunnel comprising several road-system equipment items in accordance with the invention;  
         [0034]      FIG. 2  is a perspective view from above of the road-system equipment of the invention with two covers arranged in a frame and filled with concrete;  
         [0035]      FIG. 3  is a perspective view similar to that of  FIG. 2  with one of the covers removed from the frame, and the other cover empty;  
         [0036]      FIG. 4  is a perspective view of a modular assembly with main beams and crosspieces of the frame of the road-system equipment of the invention;  
         [0037]      FIG. 5  is a perspective view from below of one of the covers of the equipment of  FIGS. 2 and 3 ;  
         [0038]      FIG. 6  is an enlarged view of the circled part at VI of  FIG. 5 ;  
         [0039]      FIG. 7  is a view of the cover of  FIG. 5  filled with a refractory material;  
         [0040]      FIG. 8  is a perspective view of one of the covers of  FIG. 2 ;  
         [0041]      FIG. 9  is a partial perspective view from below of the junction between the two adjacent covers of  FIG. 2 ;  
         [0042]      FIG. 10  is an enlarged cross-sectional view along line X-X of  FIG. 2 ;  
         [0043]      FIG. 11  is a perspective view of a casing fixed under one of the covers of the road-system equipment of  FIG. 2 ;  
         [0044]      FIG. 12  is a cross-sectional view along line XII-XII of  FIG. 2 ; and  
         [0045]      FIG. 13  is a cross-sectional view along line XIII-XIII of  FIG. 2 ;  
         [0046]      FIG. 14  is a perspective view from above of road-system equipment according to a second embodiment, and comprising two covers arranged in a frame;  
         [0047]      FIG. 15  is a perspective view similar to that of  FIG. 14  with one of the covers removed from the frame, and the other cover empty;  
         [0048]      FIG. 16  is a view from below of a cover filled with concrete according to this second embodiment;  
         [0049]      FIG. 17  is a view from above of a cover of the second embodiment, which is not filled with concrete;  
         [0050]      FIG. 18  is a cross-sectional view along line XVIII-XVIII of  FIG. 14 ;  
         [0051]      FIG. 19  is an enlarged view of the circled part at XIX of  FIG. 18 ;  
         [0052]      FIG. 20  is an enlarged cross-sectional view along line XX-XX of  FIG. 14 ; and  
         [0053]      FIG. 21  is a an enlarged cross-sectional view along line XXI-XXI of  FIG. 14 . 
     
    
     DETAILED DESCRIPTION  
       [0054]      FIG. 1  represents two road-system equipment items  1  of the invention, which can be installed in a railway tunnel T to close a technical room or gallery  2  in which technical installations are housed, such as, for example, electrical cables C.  
         [0055]     Each road-system equipment item  1  is capable of protecting, for a predetermined duration, the electrical installations in the technical gallery or room  2  from a considerable increase in the external temperature due to a fire propagating in the tunnel T.  
         [0056]     The road-system equipment of the invention which is resistant to fire or acts as a fire stop will now be described in reference to  FIGS. 2-13 , for the case where this equipment comprises two rectangular covers or plugs  3 ,  4 , which are arranged detachably in a frame  5 , in alignment and in the same plane, although it must be clearly understood that this equipment can be of the type comprising a single circular, triangular or rectangular cover or a plug, which can be housed in a frame, or several rectangular, or triangular plugs housed in the corresponding frame.  
         [0057]     The cover plug  3  has the general shape of an inverted basin whose external upper flat wall  6  is provided with a large number of continuous passages  7 , preferably in the form of oblong holes, occupying the majority of the surface of the rectangular wall  6  of the cover  3 .  
         [0058]     The upper wall  6  of the cover  3  is surrounded completely by a gutter  8 , which is delimited by raised external walls  9  of the cover  3  which are parallel to the perforated walls  1 O of the basin of this cover.  
         [0059]     The frame  5  consists of a modular assembly of main beams I  1  and crosspieces  12 , which can be assembled to each other to define the four peripheral lateral walls  13  of the rectangular frame  5 . As is more apparent from  FIG. 4 , two main beams  11  on the same side are assembled end to end by two external flat lugs  14 , which extend perpendicularly to the corresponding main beams and are held together, in juxtaposition, by at least one bolt, not shown, traversing its lugs. This figure also shows that each crosspiece  12  is fixed at each end of a main beam by means of two flat lugs  14 , which are integrally connected perpendicular to the corresponding main beam  11 , and to the end of the crosspiece  12 , respectively, in its extension, so that the two lugs  14  can be fixed to each other by being held together, in juxtaposition, by at least one traversing bolt, not shown. Thus, this modular structure makes it possible to extend, in alignment with each other, other main beams  11  with the help of external lugs  14 , depending on the number of covers one wishes to arrange in the frame  5 .  
         [0060]     The external walls  9  of the cover  3  and the bottom wall  15  of the peripheral gutter  8  constituting the seat of this cover have external faces resting, respectively, on the internal faces of the lateral walls  13  of the frame  5  and an internal peripheral ledge  16  made of the same material as the walls  13  of the frame  5 .  
         [0061]     The cover  3  comprises four lower peripheral walls  17 , which extend under the bottom wall  15  of the peripheral gutter  8  to delimit the inverted basin of the cover  3 . As is apparent notably from  FIG. 13 , the lower peripheral walls  17  are at some distance from the lateral wall parts  13  of the frame  5 , which are located below the bottom wall  15  of the gutter  8 .  
         [0062]     The basin of the cover  3  is completely filled with a heat-insulating refractory material, consisting preferably of Concrete BF cast into the basin of the cover  3 , which is represented in its inverted position in  FIG. 5 , so that the concrete not only fills this basin, but also the continuous passages  7  of the upper wall  6  of the cover  3 , coming just in contact with the external face of this wall as well as the peripheral gutter  8  by passing through holes  10   a  of the lateral walls  10  of the basin of the cover  3 . This filling with refractory material considerably decreases the thermal bridges between the cover  3  and the technical room  2 . Only the four passages  7  located at the four corners of the cover  3  are not filled with concrete and are used only for introducing a tool for lifting the cover  3  during an intervention in the technical room.  
         [0063]      FIG. 7  shows the refractory concrete BF completely filling the basin of the cover  3  of  FIG. 5 , so that the concrete is just in contact with the peripheral margins of the lower walls  17  of this cover.  
         [0064]     It is preferred for two layers of refractory concrete to be cast successively into the cover  3 , where these two layers can have different fire and mechanical resistance properties. Thus, the first layer of refractory concrete cast on the lower face of the plate  6  of the cover  3  can have a higher mechanical resistance than the second underlying layer, and a lower fire resistance and/or lower heat insulation than the second layer.  
         [0065]     Before casting the refractory concrete into the inverted cover  3 , a certain number of threaded rods  18 , in the present case four, are anchored by their respective heads  19  in plates  20 , so that the heads  19  are, respectively, opposite certain continuous passages  7  with the rods protruding from the lower face of the wall  10  of the cover  3  perpendicularly to this face. By casting the concrete into the inverted cover  3 , the concrete introduces itself particularly into the continuous passages  7  opposite the screw heads  19  to embed them in concrete and thus cut off any thermal bridge that may be created by the threaded rods  18 . Once the inverted basin  3  has been completely filled with the refractory Concrete HF, the end parts of the threaded rods  18  project from the concrete layer opposite the wall  6  of the cover  3 .  
         [0066]     A casing  21  in the form of a box with rectangular cross section, more clearly visible in  FIG. 11 , which contains a heat-insulating refractory material, is fixed under the cover  3 , so that the end edges of the lower walls  17  of the basin of this cover rest on the refractory material of the casing  21 . The refractory material does not completely fill the casing  21 , so that it leaves free the upper parts of the walls  22  of the casing, which surround, in a spaced manner, and along a space e 1 , the lower walls  17  of the basin of the cover  3 , when the casing  21  is fixed under this cover, as can be seen notably in  FIG. 12 . The casing  21 , which contains the refractory material, is fixed under the cover  3  by the threaded rods  18  that traverse the refractory material BF of the casing and the corresponding perforations  23  provided in the bottom wall  24  of the casing  21 , and by nuts  25  screwed to the free ends of the threaded rods  18  resting on the external face of the bottom wall  24 .  
         [0067]     The refractory material contained in the casing  21  can consist of refractory Concrete BF, or one or more layers of heat-insulating noncombustible plates based on calcium silicate and alumina, which in themselves are known.  
         [0068]     The lateral walls  22  of the casing  21  are arranged opposite the lower parts of the lateral walls  13  of the frame  5 , defining between themselves a space e 2 , and the bottom wall  24  of the casing  21  protrudes over a lower peripheral ledge  13   a  of the walls  13  of the frame  5  extending perpendicularly to these walls leaving a space e 3  between this ledge and the wall  24 , in which a joint J 1  made of a heat-expandable material can be housed.  
         [0069]     The walls  13  of the main beams  11  and crosspieces  12  of the frame  5  comprise openings in the form of windows  26 , which are filled with a refractory material, preferably refractory concrete, before the frame is embedded in the ground.  
         [0070]     The second cover  4  of the road-system equipment  1  presents the general structure of an inverted basin filled with a refractory material, which is substantially identical to the structure of the first cover, so that the elements of the cover  4  that are identical to those of the cover  3  bear the same reference numerals and are not described again.  
         [0071]     The difference between the cover  4  and the cover  3  concerns the fact that the upper wall  6  of the cover  4  is only bordered by the gutter  8  on three of its sides, and the free edge of the fourth side of the wall  6  rests directly on the adjacent raised external wall  9  of the cover  3 , and the cover  4  comprises, on this edge resting on the adjacent wall  9  of the cover  3 , a bar  27  extending transversely between the main beams  11  of the frame  5 , engaging under the bottom wall  15  of the gutter  8  located below the adjacent wall  9  of the cover  3 , and forming a clearance e 4  between the upper face of the bar  27  and the lower face of the wall  15  of the gutter. A heat-expandable joint J 2  can be housed in the space e 4 . In addition, the bar  27  is arranged opposite, with some separation, the adjacent lower wall  17  of the basin of the cover  3 . This assembly makes it possible to produce a fire stop baffle.  
         [0072]     A casing  21 , identical to the casing  21  of the cover  3 , is fixed under the cover  4  in the same manner as the casing  21  of the cover  3  with the help of sets of threaded rods  18  that traverse the refractory material contained in the casing  21  of the cover  4  and with nuts  25  that are screwed to the free ends of these threaded rods.  
         [0073]     The two casings  21  extend adjacently in the same plane with two of their lateral walls  22  adjacent to each other, and separated by a space e 5 .  
         [0074]     A relatively flat parallelepiped box  28 , filled with a heat-insulating refractory material, such as, for example, concrete or one or more heat-insulating noncombustible superposed layers based on calcium silicate and alumina, is arranged in part on the external faces of the two bottom walls  24  of the adjacent casings  21 , by covering, perpendicularly to the walls, the space e 5  of the adjacent walls  22  of the casings  21 , so as to increase the properties of fire resistance and/or heat insulation of the road-system equipment.  
         [0075]     It is preferred for the casing  28  to be fixed, for example, by welding, in part to the wall  24  of one of the casings  21 , for example, the one that is fixed under the cover  4 , where said wall extends perpendicularly to the wall  22  of the casing  21  and protrudes below this wall to rest directly under the bottom wall  24  of the other casing  21  when the cover  4  is arranged in the frame  5  engaging under the cover  3 . Thus the casing  28  extends perpendicularly to the plane of the space e 5 .  
         [0076]      FIGS. 14-21  represent another embodiment of the fire stop road-system equipment of the invention.  
         [0077]     According to this embodiment, the elements of the road-system equipment that present the same structure and fulfill the same functions as those of the first embodiment described above bear the same reference numerals and are not described in detail again; only the elements of the second embodiment that are different from those of the first embodiment will be described below.  
         [0078]     Thus, each of the covers  3 ,  4  of the road-system equipment consists of a basin that is right side up and comprises a peripheral ledge  15  constituting the seat of the cover and delimiting the basin of this cover into two peripheral parts, an upper  9   a  and lower  9   b  peripheral part, which have larger and smaller transverse cross sections, respectively, where the lower part  9   b  of the peripheral walls  9  of the basin of the cover  3 ,  4  is connected to the bottom wall  9   c  of the basin. The cover  3 ,  4  rests with its peripheral ledge  15  on the internal peripheral ledge  16  of the lateral walls  13  of the frame  5 , so that the lateral walls  9  of the upper part  9   a  of the basin rest on the internal faces of the lateral walls  13  of this frame, and the lower part  9   b  of the lateral walls  9  of the basin are at some distance from the lateral walls  13  of the frame  5 , as one can see more clearly in  FIG. 21 .  
         [0079]     Each basin of the covers  3 ,  4  is completely filled with a heat-insulating refractory material, such as concrete B, in such a manner that they embed the plates  29 , for example, four such plates, as represented in  FIG. 5 , which protrude from the internal face of the bottom wall  9   c  of the basin and whose upper ends comprise oblong holes  29   c  for introducing a tool or key for lifting the cover  3 ,  4  from its frame  5 , where the refractory material BF is cast into the basin to come just in contact with the ends of the plates  29 .  
         [0080]     The bottom wall  9   c  of the basin of each cover  3 ,  4  comprises perforations, for example, four perforations, for the passage of the threaded rods  18 , whose heads  19  rest on the internal face of the bottom wall  9   c  in such a manner that the threaded rods project from the bottom wall  9   c , perpendicularly to the latter. The threaded rods  18  are held so that they are integrally connected to the cover  3 ,  4  by the refractory material embedding the heads  19  of these rods in the basin.  
         [0081]     As can be seen more clearly in  FIG. 19 , all the threaded rods  18 , heads  19  and nuts  25  make it possible to detachably fix the casing  21  under the corresponding cover  3 ,  4 , so that the bottom wall  9   c  of the basin of this cover rests on the heat-insulating refractory material, such as concrete, which fills the casing  21 . In addition, the lateral walls  22  of this casing are separated by their upper parts from the lower part  9   b  of the peripheral walls  9  of the cover  3 ,  4 , along a peripheral space e 1 , thus cutting off any thermal bridge. As represented in  FIG. 20 , the cover  4  has one of its lateral walls  9  not comprising a ledge  15 , but a bar  27  integrally connected exterior to this lateral wall  9  and engaging below the ledge  15  of the other cover  3 , along an area e 4  when these two covers  3 ,  4  are arranged in the frame  5  in side-by-side opposition closing the latter. In this position, the upper part  9   a  of the wall  9  of the cover  4  rests on the upper part  9   a  of the lateral wall  9  of the cover.  
         [0082]     The road-system equipment of the invention constitutes an adaptable modular set that effectively resists fire while being also mechanically resistant, and it is easy to handle in practice like a conventional cover to gain access to the technical installations housed in the underlying gallery or technical room.  
         [0083]     The road-system equipment is arranged in such a manner that it eliminates almost all the thermal bridges that can conduct heat into the underground room. As a nonlimiting example, the road-system equipment is capable of maintaining the internal temperature of the room  2  at a value below 100° C. for two hours while the external temperature is approximately 1100° C.  
         [0084]     The road-system equipment of the invention is adaptable, that is, its fire stop performances can be improved by replacing the lower casing of the cover with another casing having a greater height, so that it can be filled with a greater thickness of heat-insulating refractory material without changing the cover.