Floor slab blocks and bridges

Abstract

To provide an abutment block capable of more efficiently constructing or manufacturing a bridge.SOLUTION: A precast floor plate block 31 constituting the bridge 1 by being placed on a bearing part of an abutment 100 is provided with a ground covering part 20 integrally molded with a floor plate part at one end along the longitudinal direction of the floor plate part 32, and the floor plate block 31 has the ground covering part whose inside length is shorter than the length in the longitudinal direction of the floor plate part. Both ends on the inner side of the ground covering part are positioned inside both ends of the floor plate part, and a connection area between the bridge 1 and a road 4 can be effectively utilized.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to floor slab blocks constituting a bridge and a bridge using the same.

Background Art

[0002] In Patent Document 1, in order to easily and efficiently join precast concrete floor slabs and construct a bridge, it is described that a ground covering is integrally formed on both sides in the short side direction of a precast concrete slab where the upper part of the truss bars protrudes from the concrete slab.

[0003] Patent Document 2 discloses a technique aimed at providing a guardrail support column and a guardrail that can suppress the overhang of the guardrail support column to the sidewalk side while ensuring the building limit, realize smooth passage on the sidewalk, and sufficiently secure impact absorption power. In this document, the guardrail support column is mainly composed of a front flange, a rear flange, and a connecting piece, and is fixed to the ground covering concrete with anchor bolts.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 1

Summary of the Invention

[0007] Since these deck blocks are integrally molded in the factory, there are no construction joints between the curb and the deck at the construction site. Therefore, there is no need to consider rusting of the reinforcing bars that make up the curb or a decrease in the strength of the construction joints, allowing the bridge to be constructed in a short time at the construction site, and also increasing the flexibility of the curb size. For this reason, the length of at least the inner part of the top surface can be made shorter than the longitudinal length of the deck, the edge of at least the inner part of the top surface can be set back from the longitudinal end of the deck, and the upper edges of at least the inner parts of the faces at both ends of the curb can be set back from the longitudinal end of the deck.

[0008] One example is a design where both inner ends of the curb are positioned further inward than both ends of the deck. By making the inner length of the curb shorter than the length of the deck, interference between vehicles and the curb can be prevented at the bridge's entrances and exits. Consequently, the dead space between the road accessing the bridge and the bridge itself can be reduced, and the connection areas with roads at both ends of the bridge and / or nearby can be effectively utilized.

[0009] The outer ends of the curb may be positioned inward from the ends of the floorboard, the outer length of the curb may be longer than the inner length, and it may include obliquely cut surfaces at both ends in the longitudinal direction. At least one of the surfaces at both ends of the curb may include a surface that is inclined upward. A portion of the surface that is inclined upward may include an area that reflects car headlights. Reflective material may be embedded or attached in the reflective area. The angle of the reflective area may differ from that of the surfaces that are inclined upward at both ends of the curb. Furthermore, at least a portion of the inner surface of the curb may include an area that reflects car headlights. A component that reflects car headlights may be attached to at least a portion of the upper surface of the curb. This can improve the identifiability or visibility of both ends of the curb.

[0010] Another aspect of the present invention is a bridge having an abutment and a deck block placed on the support portion of the abutment. The bridge comprises a bridge abutment, a deck block including a deck plate portion with both ends in a first direction resting on the support portion of the bridge abutment, and a curb portion provided at the end of the deck plate portion along the first direction, wherein the deck plate portion inside the curb portion is an area used for the passage of vehicles, and at least the upper side of the inner side of at least one end of the curb portion in the first direction is set back from one of the ends of the deck plate portion in the first direction. A base plate is provided at one end of the base plate along its longitudinal direction, with a base plate whose length, at least the inner length of its upper surface, is shorter than the longitudinal length of the base plate. The inner end of the upper surface of the base plate may be set back from the longitudinal end of the base plate, and the upper end of at least one of the surfaces at both ends of the base plate may be set back from the longitudinal end of the base plate. The inner ends of the base plate may be set inward from the ends of the base plate. The outer ends of the base plate may be at the same position as the ends of the base plate, or they may be set inward from the ends of the base plate. If the outer length of the base plate is longer than the inner length, the base plate may include obliquely cut surfaces at both ends in the longitudinal direction.

[0011] At least one face at each end of the curb may include a face that is inclined upward. A portion of the face that is inclined upward may include an area that reflects the lights of vehicles. The abutment may include a number of precast abutment blocks arranged in the width direction, with precast deck blocks without curbs placed between deck blocks with curbs. The bridge may have handrails provided on top of the curb. [Brief explanation of the drawing]

[0012] [Figure 1] A diagram showing an overview of the constructed bridge. [Figure 2] A diagram showing the state of constructing the bridge. [Figure 3] A diagram showing an example of the constructed bridge. [Figure 4] A diagram showing another example of the constructed bridge. [Figure 5] A diagram showing the state of connecting the abutment block and the floor slab block. [Figure 6] A diagram showing the state of linking the abutment block and the floor slab block. [Figure 7] A diagram showing the state of constructing the bridge with the abutment block and the floor slab block. [Figure 8] A diagram showing the state of the bridge viewed from above. [Figure 9] An end view and a sectional view of the superstructure of the bridge. [Figure 10] A diagram showing the formwork for prefabricating the floor slab block. [Figure 11] A diagram showing the plan view, bottom view, front view, rear view, side view and sectional view of the floor slab block. [Figure 12] A diagram showing another example of the superstructure of the bridge. [Figure 13] A diagram showing the plan view, bottom view, front view and rear view of different examples of the floor slab block. [Figure 14] A diagram showing another example of the superstructure of the bridge. [Figure 15] A diagram showing another example of the superstructure of the bridge. [Figure 16] A diagram showing an overview of another example of the constructed bridge. [Figure 17] A diagram showing the state of the bridge viewed from above. [Figure 18] A diagram showing the state of the superstructure of the bridge viewed from above. [Figure 19] An end view and a sectional view of the superstructure of the bridge. [Figure 20] A sectional view showing some examples of the ends of the ground covering part. [Figure 21] A diagram showing the state of different examples of the superstructure of the bridge viewed from above. [Figure 22] A perspective view showing different examples of floorboard blocks. [Modes for carrying out the invention]

[0013] Figure 1 shows an overview of a bridge (bridge, bridge structure) which is an example of the present invention. Figure 2 shows the manufacturing (construction) of bridge 1. Bridge 1 is a structure that crosses over obstacles such as a river 2, and includes abutments 100 located on both sides 3 of the riverbank 5 of the river 2, and deck slab blocks 30 and 31 supported by the abutments 100 on both sides and positioned to straddle the river 2. An example of a deck slab block 31 is equipped with a curb 20, and bridge 1 includes a protective fence (handrail, railing) 40 installed on the curb 20. The abutments 100 are factory prefabricated (precast) as a single unit and are constructed by installing multiple abutment blocks 10 equipped with a high-strength superstructure 11. The deck slabs 30 and 31 are also factory prefabricated (precast), and the deck slab blocks 31 on both sides are precast including the curb 20. Therefore, Bridge 1 can be constructed in a short period of time by assembling these precast concrete blocks (parts) 10, 30, and 31 on-site, and the labor required for construction can also be reduced.

[0014] One example of bridge 1 is suitable for bridges 1 constructed for purposes such as installing a road 4 with a wheel load of, for example, 8 tons or more, at sites where the span (distance between abutment blocks) exceeds 3m and is generally 10m or less, and more preferably 8m or less. Furthermore, it is suitable for construction of bridge 1 with the shortest possible span in locations where there are existing revetment structures 5 in rivers 2, etc., while largely preserving the revetment structures 5 and without damming or altering the flow of the river 2. Note that the above figures are examples and are not limiting.

[0015] As shown in Figure 2, the abutment block 10 for assembling the abutment 100 has an upper part (superstructure, floor slab support part, floor slab support structure) 11 which includes a support part 15 that supports the floor slab blocks 30 and 31 provided on the front (inner) side 19a, and a parapet part 16 at the rear 19b that rises from the support part 15. The abutment block 10 further has this upper part 11, a vertical wall part 12 that supports the upper part 11, and a footing part 13 that extends forward 19a and rear 19b to support the vertical wall part 12, and these are precast as a single inverted T-shaped concrete abutment block. The back of the retaining wall 5 of the revetment is excavated to the extent that the abutment block 10 can be transported in and installed, and the abutment block 10 is installed (constructed). Subsequently, the bridge 1 equipped with the deck slab section 32 can be constructed by placing (mounting) the deck slab block 31, which has a prefabricated deck slab block 30 and / or curb 20, on top of the abutment block 10. When the abutment block is constructed by casting in place, additional space is required for assembling and removing the formwork, but such space is not required for the precast abutment block 10 in this example. One example of a deck slab block is a block 31 consisting only of the deck slab section, while another example is a deck slab block 31 in which the curb section 20 and the deck slab section 32 are integrated. The following explanation will refer to the deck slab block 31, but the method of connection to the abutment 100 is common to all.

[0016] For example, a foundation concrete layer 7 containing foundation crushed stone and base concrete may be constructed in the excavated area 9, and the abutment blocks 10 may be installed on top of it via grout for height adjustment. This method allows the abutment blocks 10 to be constructed without demolishing the retaining wall 5, and since the abutment blocks 10 are precast, a curing period is basically unnecessary, and the bridge 1 can be constructed in a short period of time.

[0017] Furthermore, inserts 61 are embedded in the support surfaces 15a of each support portion 15 of the abutment block 10 that assembles a pair of abutments 100. By screwing anchor bars 80 into the inserts 61 and inserting them into through holes 33 provided in the deck plate 31, the abutments 100 and the deck plate 31 can be easily combined on-site to construct the bridge 1. The anchor bars 80 could be embedded in the support surfaces 15a on-site, but this would be time-consuming and would damage the support surfaces 15a that support the deck plate blocks (deck plates) 31, reducing durability. By embedding the inserts (embedded metal fittings) 61 in the support surfaces 15a in advance and attaching the anchor bars 80 to them, the anchor bars (anchor pins) 80 can be installed embedded in the abutment 100.

[0018] Figure 3 shows a top view of bridge 1. This bridge 1 is constructed to connect roads 4 and 4a located on both sides of the revetment 5. The precast deck slab block 31 that constitutes bridge 1 by being placed on the support portion 15 of the abutment 100 includes a curb portion 20 integrally molded with the deck slab portion 32 at one end along the longitudinal direction X of the deck slab portion 32. The length 21 of the inner side 21 of the curb portion 20 relative to the outer side 22 of the deck slab block 31 (more specifically, the length 21 of the inner side 21 of the upper surface 25 of the curb portion 20) 21w is shorter than the length 32w of the longitudinal direction X of the deck slab portion 32, and both inner ends (both upper ends) 21a of the curb portion 20 are located inward from both ends 32a of the deck slab portion. Therefore, the curb portion 20 is less likely to obstruct traffic at the section connecting bridge 1 to road 4 or 4a. Therefore, as shown by the dashed line 110, the area of ​​the floor plate section 32 at the connection point with the road 4 (connection area) can be used for the passage of vehicles and people. Thus, almost the entire width 1w of the bridge 1 can be effectively utilized for the passage of vehicles and the like.

[0019] Furthermore, as shown in the road 4a on the left, the end 32a of the floor plate section 32 can also be used as part of road 4a. Therefore, roads 4 and 4a can be constructed closer to the revetment 5, and even roads 4 or 4a that are close to the revetment 5 can be easily connected by the bridge 1. The guardrail 49 may also be installed on the revetment 5.

[0020] Figure 4 shows, for reference, a bridge 101 using a deck block 131 in which both ends 121a of the inner part 121 of the curb 120 extend to both ends 132a of the deck section 132. As shown by the dashed line 119, the area where vehicles can pass is limited by the curb 120 extending to both ends of the deck section 132. Therefore, even if bridge 101 has the same width 1w as bridge 1, the passage space at the connection point with road 4 is limited, and the width 101w that can be used for vehicle traffic within the bridge width 1w is effectively limited. Also, as shown in road 4a in Figure 3, it is not possible to use part of the deck section 132 as a road, and road 4 must be constructed at a certain distance from the revetment 5.

[0021] The width (length in the direction perpendicular to the longitudinal direction X) and height (length protruding from the floor plate section 32) of the curb section 20 may be 200 to 400 mm, or 300 to 350 mm. The cross-section of the curb section 20 may be a square, a rectangle with a longer height, or a rectangle with a longer width. The distance (on one side) from the end 32a of the floor plate section 32 to the end 21a of the inner side 21 of the curb section 20 may be about 1 to 4 times the width of the curb section 20, about 1.5 to 3.5 times, or about 2 to 3 times. In a floor plate block 31 in which the curb section 20 and the floor plate section 32 are integrally molded (precast) in a factory, it is superior in terms of durability and strength compared to when the curb section 20 is constructed on site, and the width of the curb section 20 can be reduced. Therefore, in this respect as well, a wide bridge 1 that can be used for the passage of vehicles can be provided.

[0022] Figures 5 to 7 illustrate an enlarged view of one end of the floor slab block 31. The floor slab block (floor slab) 31 is provided with through holes 33 for connection or linking on both sides in its longitudinal direction. By inserting anchor bars 80 into these holes, the floor slab 31 is attached to the abutment 100, and the bridge 1 is assembled. An example of an anchor bar 80 includes a main anchor pin (reinforcement bar) 81 and an elastic cover (column, resin, elastic member) 82 that covers its upper part (upper half). The lower part (lower half) of the anchor pin 81 is provided with a threaded portion 83 for screwing into an insert 61. With the elastic cover 82 of the anchor bar 80 inserted into the through hole 33, the through hole 33 is filled with a hard filler material 39 such as concrete. This creates a space 89 inside the through hole 33 in which the anchor bar 80 can move around due to the elasticity of the elastic cover 82. A floor slab 31 with a curb 20 can be similarly attached to the abutment 100. Instead of the anchor bar 80 with the elastic cover 82, a reinforcing bar 81 may be inserted, and an elastic material such as urethane or butyl rubber may be packed around it.

[0023] In this bridge 1, the deck slab 31 is supported by resting it on the bearing surfaces 15a of the abutments 100 on both sides. That is, a movable area 89 is provided around the anchor bar 80, and the deck slab 31 is mounted (placed) on the bearing surface 15a in a state that allows it to move back and forth (left and right). On the other hand, the anchor bar 80 is inserted into the through hole 33 and fits inside, so the deck slab 31 can also be prevented from falling. Therefore, the bridge 1 has a simple structure that combines the functions of a simple beam with fall prevention.

[0024] For bridges with a length of several meters to about 10 meters, when installing the deck slab 31 on the abutment, it may be considered to attach the abutment and the deck slab using anchor bars (reinforcement bars). The reinforcement bars of the anchor bars may be embedded in the predetermined positions during the construction of the abutment. Alternatively, after the abutment is completed, holes may be drilled in the support section of the abutment and the anchor bars may be installed in these holes, and then the holes around the anchor bars may be filled with concrete. After that, the procedure of placing the perforated deck slab on the abutment and filling the gaps with concrete may be adopted.

[0025] One of the problems with this method is the difficulty in positioning the anchor bars accurately. When anchor bars are installed in wet concrete before it has hardened, the protruding portion (reinforcement) is heavy, making the anchor bars prone to tilting and sinking. Therefore, in order to install the anchor bars in the specified position and shape, it is necessary to prepare anchor frames or other components, resulting in a large-scale construction project. Furthermore, although the holes in the deck slab should be kept as small as possible to minimize cross-sectional loss, construction constraints often force the holes in the deck slab to be made larger. If the support sections are drilled after the abutment is completed, the cross-sectional loss becomes large, reducing the strength of the support sections that are constantly subjected to impact loads from vehicles. In addition, even if the anchor bars fit within the allowable range of the holes in the deck slab and are fixed in place, both ends of the deck slab will be fixed to the abutment, making it difficult to obtain the strength required for structural calculations as a simply supported beam.

[0026] In the example of bridge 1, the abutment 100 is constructed from prefabricated abutment blocks 10, and the above problem is solved by embedding inserts 61 in predetermined locations on the bearing surface 15a of the abutment blocks 10. By embedding the inserts 61 in the abutment blocks 10 during precasting, the inserts 61 can be embedded in a highly accurate position without reducing the strength of the bearing surface 15a. Furthermore, by installing (screwing in) anchor bars (anchor pins) 80, which have threaded portions 83 on at least the lower half, into the inserts 61 on site, the anchor bars 80 can be embedded in the bearing surface 15a, or remain embedded, without shifting or tilting. Therefore, through holes 33 of the minimum diameter can be provided in the floor plate 31 with almost no consideration for errors in the installation position and orientation of the anchor bars 80.

[0027] The method of inserting anchor bars 80 embedded in the bearing surface 15a into through holes 33 provided in the floor slab blocks 31 and filling the through holes 33 with a hard filler material such as mortar or concrete is suitable for constructing the bridge 1 in a short period of time. A different problem with this method is that the mortar or concrete 39 filling the through holes 33 may sink. That is, the mortar or concrete 39 filled on site, although having sufficient strength, differs from the prefabricated floor slab 31 in terms of density, etc. Therefore, it tends to be gradually compressed downwards due to pressure, vibration caused by vehicles passing over the bridge 1, and repeated displacement of the floor slab blocks 31, causing the surface to sink. When the concrete 39 filling the through holes 33 sinks due to this phenomenon, it becomes easier for debris and drainage to accumulate on top of the through holes 33, resulting in an unsightly appearance. In addition, the area around the anchor bars 80 may be compressed, potentially compressing the space 89 in which the anchor bars 80 can move.

[0028] Therefore, the through-hole 33 that penetrates the floor slab 31 includes a tapered sealing portion 38 that is wider at the top and narrows at the bottom, near the upper opening (upper part) 36 into which mortar or concrete 39 is injected. For example, the through-hole 33 includes an intermediate portion 34 with a smaller diameter than the upper opening 36, and as shown in Figure 4, a space 89 for the anchor bar 80 to move is formed below the sealing portion 38, where the lower diameter is narrower than the upper diameter. Therefore, in the through-hole 33 that penetrates the floor slab 31, even if pressure is applied from above, the injected mortar or concrete 39 will not move downward due to the tapered structure or stepped structure of the sealing portion 38, which is narrower at the bottom, and the space 89 formed by the elastic cover 82 around the anchor bar 80 inserted into the through-hole 33 will not be crushed by the mortar or concrete 39. Therefore, the space 89 for the anchor bar 80 to move is secured by the elastic cover 82, and its function as a roller pivot point is maintained.

[0029] Furthermore, the narrower lower part of the sealing portion 38 makes it difficult for the hard mortar or concrete filler 39 injected into and hardened in the sealing portion 38 to move below the sealing portion 38. As a result, the filler 39 filling the upper opening 36 of the through hole 33 is less likely to sag, and sagging that can cause water to accumulate and dirt to form is less likely to occur on the surface of the floorboard 31. The through hole 33 may also have a lower opening 35 at its lowest point that opens downwards to facilitate the insertion of the anchor bar 80.

[0030] Figure 8 shows a view from above of the bridge 1 assembled from the abutment block 10 and the deck slab blocks 30 and 31. Figure 9(a) shows the end of the bridge superstructure 41 assembled from the deck slab blocks 30 and 31, and Figure 9(b) shows the bridge superstructure 41 in a cross-section of the center. The central deck slab block 30 is made of a single, almost flat precast plate, while the left and right deck slab blocks 31 have the curb 20 and deck slab section 32 integrally molded.

[0031] For example, the deck blocks 30 and 31 are 2m wide and 8m long, and a bridge 1 with a total width of 6m and a span of 8m is constructed using 3x2 abutment blocks 10 arranged on both sides, and a total of 3 deck blocks 30 and 31. The deck block 31 has the deck section 32 and the curb section 20 molded as one piece. The upper end 22a of the outer 22 of the upper surface (top) 25 of the curb section 20, together with the upper end 21a of the inner 21, is located inward (recessed) from the end 32a of the deck section 32, and the lower end 22b of the outer 22 and the lower end 21b of the inner 21 of the curb section 20 are also located recessed from the end 32a of the deck section 32. As a result, both ends 23 of the curb section 20 are surfaces that are approximately perpendicular to the longitudinal direction X. The ends of the curb section 20 are formed similarly.

[0032] Figure 10 shows an example of a formwork 29 for manufacturing a concrete floor slab block 31 in which the curb section 20 and floor slab section 32 for installing the handrail 40 are integrally molded. By prefabricating (precasting) the curb section 20 and floor slab section 32 as a single unit in the factory, the on-site construction period can be shortened. Furthermore, since there is no construction joint between the curb section 20 and the floor slab section 32 at the site, there is no need to consider rusting of the reinforcing bars or a decrease in the strength of the construction joint, and the width of the curb section 20 can be made thinner. In addition, by making the length of the curb section 20 shorter than the length of the floor slab section 32, interference between vehicles and the curb section 20 at the entrance and exit of the bridge 1 can be prevented.

[0033] Figure 11 shows a floor slab block 31. Figure 11(a) is a plan view, Figure 11(b) is a bottom view, Figure 11(c) is a front view, Figure 11(d) is a rear view, Figure 11(e) is a right side view, and Figure 11(f) is a cross-sectional view, with the left side being symmetrical to the right side. In this example, there are two through holes 33 at each end, but there may be one at each end, or three or more.

[0034] Figure 12 shows a top view of the superstructure 41 of a bridge 1 using a deck block 31 with a curb section 20 of different shapes. The deck block 31 includes a curb section 20 integrated with a deck section 32, and the length of the inner side 21 of the curb section 20 is shorter than the length of the deck section 32. The length of the outer side 22 of the curb section 20 is greater than the length of the inner side 21, and the surfaces 23 at both ends in the longitudinal direction X are surfaces that are cut diagonally inward. That is, the inner end (upper end) 21a of the upper surface 25 of the curb section 20 is set back inward from the end 32a of the deck section 32, and the lower end 21b is also set back inward. On the other hand, the outer end (upper end) 22a and the lower end 22b of the upper surface 25 of the curb section 20 are at the same position as the end 32a of the deck section 32. Therefore, the end surfaces 23 of the curb section 20 are surfaces that are inclined inward. By shortening the length of the inner 21 of the curb section 20 and setting back the inner ends 21a and 21b, the connection portion (connection area) with the road 4 can be effectively utilized, similar to the bridge 1 using the floor slab block 31 described above. In addition, by lengthening the length of the outer 22 of the curb section 20 and making the angle of the faces 23 at both ends gentler, it can be made to look better and give the impression that it will not obstruct the passage of vehicles, etc. The ends 22a of the outer 22 of the curb section 20 may be in the same position as the ends 32a of the floor slab section 32, or they may be set inward. That is, the end faces 23 of the curb section 20 may extend diagonally inward from the ends 32a of the floor slab section 32, or they may extend diagonally inward from a position set back from the ends 32a of the floor slab section 32.

[0035] Figure 13 shows the floor slab block 31 as described above. Figure 13(a) is a top view, Figure 13(b) is a bottom view, Figure 13(c) is a front view, and Figure 13(d) is a rear view. The right side, left side, and cross-sectional views are the same as those of the floor slab block shown in Figure 11.

[0036] Figures 14 and 15 show a top view of the superstructure 41 of the bridge 1 using yet another example of a floor slab block 31. The size of the curb section 20 relative to the floor slab section 32 may vary depending on the size of the floor slab section 32, as shown by the shaded lines in each figure, and is not limited to these. In all floor slab blocks 31, the length of the inner side 21 is shorter than the length of the floor slab section 32, and the end 23 is located inward. As a result, the end 23 acts as a corner cut, making it possible to construct a bridge 1 that is easily accessible for vehicles and people.

[0037] Figure 16 shows a bridge 1 constructed using yet another deck block 31. Figure 17 shows a top view of the bridge 1. This deck block 31 is also a precast deck block 31 that constitutes the deck section 32 of the bridge 1 by being placed on the support section 15 of the abutment 100, which is composed of multiple abutment blocks 10. The deck block 31 includes a curb section 20 that is integrally molded with the deck section 32 at one end along the longitudinal direction of the deck section 32. The length 21w of at least the inner 21 of the upper surface 25 of the curb section 20 is shorter than the longitudinal length 32w of the deck section 32. Also, the end 21a of at least the inner 21 of the upper surface 25 of the curb section 20 is set back (inward) from the longitudinal end 32a of the deck section 32. Furthermore, the upper end 21a of at least one inner surface 21 of at least one of the surfaces 23 at both ends of the base plate 20 is located set back from the longitudinal end 32a of the floor plate 32.

[0038] Furthermore, the floor slab block 31 has at least one surface 23 at both ends of the curb section 20 that is inclined upward. That is, the upper end 21a of the inner 21 and the upper end 22a of the outer 22 of the surfaces 23 at both ends of the curb section 20 are set back inward from the lower ends 21b and 22b, forming an upward-facing inclined surface. The lower ends 21b and 22b may be in the same position as the end 32a of the floor slab section 32, or they may be set back inward. On this inclined surface 23, the lower ends 21b and 22b, which are closer to the end 32a of the floor slab section 32, are lower than the upper ends 21a and 22a. Therefore, the surfaces 23 at both ends of the curb section 20 are less likely to interfere with the tires of vehicles turning to enter and exit the bridge 1. For this reason, similar to the floor slab block 31 described above, it is possible to construct a bridge 1 that allows vehicles to easily enter and exit while changing direction.

[0039] Furthermore, in the floor slab block 31 of this example, a region 50 that reflects car headlights is formed on a part of the inclined surface 23 that faces upward at both ends of the curb 20. By providing a reflective region 50 on the surface 23 that faces diagonally upward, the headlights of cars entering the bridge 1 can be reflected diagonally upward, making it easier to identify (visualize) the positions of both ends of the curb 20 even at night. The reflective region 50 may be formed with reflective paint or the like. Reflective material 51 may be embedded in the reflective region 50 when the floor slab block 31 is precast. Reflective material 51 may be attached to the reflective region 50 after the floor slab block 31 is precast, or during the construction of the bridge 1.

[0040] Furthermore, in the floor slab block 31 of this example, a portion of the inner surface (inner surface) 26 of the curb portion 20 is provided with multiple light-reflecting areas 50, either intermittently or continuously. Reflective paint may be applied to the reflective areas 50 of the inner surface 26, or reflective material 51 may be embedded or attached.

[0041] Figure 18 shows different examples of bridge 1 assembled from abutment blocks 10 and deck slab blocks 30 and 31, viewed from above. Figure 19(a) shows the end of the bridge superstructure 41 assembled from deck slab blocks 30 and 31, and Figure 19(b) shows a cross-section of the structure of the curb 20. In this example as well, the central deck slab block 30 is made of a single, almost flat precast plate, and the left and right deck slab blocks 31 are integrally molded with the curb 20 and deck slab 32. The deck slab block 31 has the deck slab 32 and curb 20 integrally molded, and the upper ends 21a and 22a of the inner 21 and outer 22 of the upper surface (top) 25 of the curb 20 are set inward from the lower ends 21b and 22b, and upwardly inclined surfaces 23 are formed at both ends of the curb 20. Furthermore, the lower ends 21b and 22b of the base plate 20 are set back from the end 32a of the floor plate 32, and the upward-facing surfaces 23 at both ends of the base plate 20 are set back inward from both ends 32a of the floor plate 32, further reducing the likelihood of interference with the vehicle's tires.

[0042] Furthermore, the inclined surface 23, which faces upward, is provided with a region 50 that reflects car headlights. The angle of the reflecting region 50 is adjusted by making the angle steeper or gentler relative to the inclined surface 23, so that the car headlights are reflected in a way that is easily visible to the driver.

[0043] Figure 20 shows several examples of surfaces 23 that are inclined upward at the ends (both ends) of the curb section 20. In Figure 20(a), a reflective surface (region) 50 is formed above the inclined surface 23, extending from the upper surface 25 of the curb section 20, and a reflective material 51 is embedded in the reflective surface 50. An example of the reflective material 51 is an embedded object that includes a diamond-cut surface. The reflective surface 50 may be at the same angle as the inclined surface 23, or it may be set at an angle that better reflects car headlights toward the driver.

[0044] Figure 20(b) shows a reflective surface 50 formed near the center of the inclined surface 23, with a reflective material 51 embedded in it. Figure 20(c) shows a reflective surface 50 formed by attaching the reflective material 51 to the center of the inclined surface 23 with adhesive or the like. Figure 20(d) shows an example in which a reflective member 52, which has an upwardly inclined reflective surface 52a, is attached to the upper surface 25 of the base portion 20 instead of the inclined surface 23.

[0045] Figure 21 shows another example of a bridge 1 assembled from abutment blocks 10 and deck blocks 30 and 31, viewed from above. The deck block 31 is equipped with a curb 20, and reflective material 52 is intermittently attached to a portion of the upper surface 25 of the curb 20. The reflective material 52 has reflective surfaces 52a that are angled upward on all four sides, and can reflect light from car headlights in a way that makes it easily visible to drivers. Therefore, even at night, a bridge 1 can be provided in which the curb 20 is easily recognizable.

[0046] Figure 22 shows a magnified view of the vicinity of the end 32 of yet another floor slab block 31. This floor slab block 31 is also a precast concrete block that constitutes the floor slab portion 32. The floor slab block 31 includes a base portion 20 that is integrally molded with the floor slab portion 32 at one end along the longitudinal direction of the floor slab portion 32. The inner upper end 21a and lower end 21b, and the outer upper end 22a and lower end 22b of the upper surface 25 of the base portion 20 are set back (inward) from the longitudinal end 32a of the floor slab portion 32, and both ends of the base portion 20 include an upwardly inclined surface 23a and an inner surface 23b that is inclined inward and upward. A reflective area 50 is provided by embedding reflective material (reflector) 51 in a portion of each of the upwardly inclined surfaces 23a and 23b. It is possible to construct the bridge 1 using this floor slab block 31, with both ends of the curb section 20 slanted upward and inward, and reflectors 51 embedded at both ends facing upward and inward. As a result, both ends of the curb section 20 are easily visible to car headlights even at night, and the bridge 1 can be provided that is less likely to interfere with car tires when approaching the bridge 1 while turning.

[0047] As described above, by using the precast floor slab block 31 of the present invention, it becomes possible to construct and provide a highly durable bridge 1 equipped with a curb section (curb) 20 in a short period of time and at low cost. [Explanation of symbols]

[0048] 1 bridge section, 10 abutment blocks, 20 curb sections 30, 31 Floorboards (floorboard blocks), 32 Floorboard section

Claims

1. A precast floor slab block having a floor slab portion, wherein both ends of the floor slab portion in the first direction are placed on the support portions of the bridge abutment to constitute a bridge, A floorboard block having a curb portion integrally molded with the floorboard portion at one end of the floorboard portion along the first direction, wherein the floorboard portion inside the curb portion is an area used for the passage of vehicles, and at least one of the ends of the floorboard portion in the first direction becomes an entrance to the bridge for the vehicle to turn in and out of the bridge, and at least the upper inner side of at least one end of the curb portion in the first direction is set back from at least one of the ends of the floorboard portion in the first direction so as to suppress interference between the tires of the vehicle turning in and out of the bridge and the curb portion.

2. In Claim 1, A floorboard block in which the length in the first direction between the upper inner sides of both ends of the base portion in the first direction is shorter than the length in the first direction of the floorboard portion.

3. In claim 1 or 2, A floorboard block in which the inner lower side of at least one end of the base portion in the first direction is set back from one of the ends of the floorboard portion in the first direction.

4. In claim 1 or 2, A floorboard block in which the upper outer side opposite to the inner side of at least one end of the base portion in the first direction is set back from one of the ends of the floorboard portion in the first direction.

5. In claim 4, A floorboard block in which the lower outer side of at least one end of the base portion in the first direction is set back from one of the ends of the floorboard portion in the first direction.

6. In claim 1 or 2, The floorboard block, wherein at least one end of the base portion in the first direction includes the surface that extends diagonally inward.

7. In claim 1, The floorboard block, wherein at least one end of the base portion in the first direction includes a surface inclined upward.

8. A precast floor slab block having a floor slab portion, wherein both ends of the floor slab portion in the first direction are placed on the support portions of the bridge abutment to constitute a bridge, A floorboard block having a curb portion integrally molded with the floorboard portion at one end of the floorboard portion along the first direction, wherein the floorboard portion inside the curb portion is an area used for the passage of vehicles, and at least one of the ends of the floorboard portion in the first direction becomes an entrance to the bridge for the vehicle to turn in and out of the bridge, and at least the upper inner side of the surface of at least one end of the curb portion in the first direction is set back from at least one of the ends of the floorboard portion in the first direction so as to suppress interference between the tires of the vehicle turning in and out of the bridge and the curb portion.

9. In claim 8, A floorboard block in which at least one end surface of the base portion in the first direction includes a surface that is inclined to face upward.

10. In claim 7 or 9, The aforementioned upward-facing inclined surface includes a portion of the surface that reflects the headlights of a car, forming a floor block.

11. In claim 10, A floorboard block in which a reflective material is embedded or attached to the aforementioned reflective area.

12. In claim 10, A floorboard block in which the angle of the reflective region is different from that of the surface inclined to face upward.

13. In claim 1 or 8, A floorboard block having at least a portion of its inner surface on the aforementioned base portion that includes an area that reflects the lights of a car.

14. In claim 1 or 8, A floorboard block having a component that reflects car headlights attached to at least a portion of the upper surface of the aforementioned base plate.

15. A bridge having an abutment and a deck block including a deck plate portion on which both ends in a first direction are placed on the support portion of the abutment, A bridge having a curb provided at the end of the floor plate portion along the first direction, wherein the floor plate portion inside the curb is an area used for the passage of vehicles, at least one of the ends of the floor plate portion in the first direction is an entrance to the bridge into and out of the bridge for vehicles to turn, and at least the upper inner side of at least one end of the curb portion in the first direction is set back from at least one of the ends of the floor plate portion in the first direction so as to suppress interference between the tires of vehicles turning into and out of the bridge and the curb.

16. In claim 15, A bridge in which the length in the first direction between the upper inner sides of both ends of the curb portion in the first direction is shorter than the length in the first direction of the deck plate portion.

17. In claim 15 or 16, A bridge in which at least one end of the curb portion in the first direction includes the surface that extends diagonally inward.

18. In claim 15, A bridge in which at least one end of the curb portion in the first direction includes a surface that is inclined upward.

19. A bridge having an abutment and a deck block including a deck plate portion on which both ends in a first direction are placed on the support portion of the abutment, A bridge having a curb provided at the end of the floor plate portion along the first direction, wherein the floor plate portion inside the curb is an area used for the passage of vehicles, at least one of the ends of the floor plate portion in the first direction is an entrance to the bridge into and out of the bridge into and out of the bridge as the vehicle turns, and at least the upper inner side of the surface of at least one end of the curb portion in the first direction is set back from at least one of the ends of the floor plate portion in the first direction so as to suppress interference between the tires of the vehicle turning into and out of the bridge and the curb.

20. In claim 19, A bridge in which at least one end surface of the abutment in the first direction includes a surface that is inclined upward.

21. In claim 18 or 20, A bridge in which the aforementioned upward-facing inclined surface includes an area on that surface that reflects the headlights of a car.

22. In claim 15 or 19, A bridge having at least a portion of the inner surface of the aforementioned curb section that includes an area that reflects the lights of a car.

23. In claim 15 or 19, A bridge having a component that reflects car headlights attached to at least a portion of the upper surface of the aforementioned curb.

24. In claim 15 or 19, The abutment includes a plurality of precast abutment blocks arranged in a width direction perpendicular to the first direction, A bridge in which precast deck blocks without a curb are placed between deck blocks having a curb.

25. In claim 15 or 19, A bridge having a handrail provided on the aforementioned curb.