JP4506316B2 - Road leveling structure - Google Patents

Description

  The present invention relates to a road leveling elimination structure on a soft ground in which a structure is embedded.

  On roads constructed on soft ground, uneven subsidence is caused by structures such as underground pipes, box culverts, and abutments provided in the middle of the road, which are buried by crossing or traversing the road. For example, steps or cracks occur at the boundary between the underground roadbed of the underground pipe or box culvert and the other roadbed, and at the boundary between the abutment and the upper roadbed of the soft ground or backfill embankment. It is known.

  Normally, such steps and cracks are repaired by patching, overlaying, and pavement replacement, but by doing so, a new increased load is generated and further subsidence occurs. Is 3 to 5 years (about half a year to 1 year for ultra-soft ground) and the repair work is complicated, so that drastic improvement has been demanded.

  On the other hand, as a road construction method for soft ground, the soft ground is dug down along the road construction position, lightweight foamed resin blocks made of foamed polystyrene etc. are stacked and laid, and then embankment is applied. A construction method for constructing a roadbed on top is known. (For example, refer to Patent Document 1).

  In addition, an asphalt mixture layer that can be plastically deformed is buried under the pavement of the embankment part as a structure to eliminate steps and cracks in the pavement at the boundary between the abutment and the embankment part of the road. In addition, one in which one end portion of the asphalt mixture layer is fixed to an abutment has been proposed (see, for example, Patent Document 2).

JP 2000-73302 A JP-A-8-151602

  In the road level difference elimination structure described in Patent Document 2, a step or crack at the boundary between the abutment and the embankment can be prevented, but a notch for fixing and mounting one end of the asphalt mixture layer is provided at the upper end of the abutment. It is difficult to adapt to existing roads, the work for fixing one end of the asphalt mixture layer to the abutment is complicated, and the asphalt mixture layer itself is a foamed resin block. It is a heavy object compared to the above, and an increased load is generated, further subsidence occurs, workability is not good, and the asphalt mixture layer in a relatively short range from the abutment to the outer edge of the asphalt mixture layer Due to the fact that steps and cracks are absorbed by plastic deformation, the road gradient above the asphalt mixture layer becomes large, and a strong impact is applied from the road surface when the vehicle is running. Or Flip, such as Mi距 may become shorter, that the function of the road is reduced, there are problems such as.

  The purpose of the present invention is to prevent road surface steps and cracks at the boundary between the structure embedded in the road and the soft ground for a long period of time, and to suppress the increase in workability and construction cost, and can be applied over a wide range Thus, it is an object to provide a road leveling structure that can be configured so that the slope of the road near the structure gradually changes even when the soft ground sinks.

  As shown in FIG. 1, the present inventor, as shown in FIG. 1, on a road R on soft ground N in which a structure K is buried in a transverse shape, due to uneven settlement of the road surface M, a road surface M <b> 1 indicated by a one-dot chain line Since both sides of the structure K sink to the center and the gradient change of the road surface M1 on the upper side of the structure K increases, steps and cracks occur, and a strong impact is applied from the road surface M1 when the vehicle is traveling. Paying attention to the feeling and the visual distance shortening, the load load is reduced by embedding a lightweight foamed resin block in the level section L in the vicinity of the structure K like the road surface M2 indicated by a two-dot chain line. To reduce the stress applied to the soft ground N as much as possible, and in the rubbed section S outside the level section L, the load load is evenly distributed to the soft ground N by a net member such as a geogrid. , By reducing the uneven settlement of the road surface M, inspired and can solve the above problems, and have completed the present invention.

The first road leveling structure according to the present invention is a road leveling structure on a soft ground in which a structure is embedded or installed transversely to the road. A lightweight embankment layer is embedded in a substantially horizontal direction on the side, and a net member linked to the light embankment layer is projected outwardly from the light embankment layer at a site where the soft ground outside the light embankment sinks unevenly. It is embedded in the horizontal direction on the lower side. In the present invention, “road” means a concept including a roadway and a sidewalk. “Lightweight embankment layer” means an embankment layer having a unit volume mass of 1.1 t / m 3 or less. Specifically, it is a foam-mixed lightweight soil (FCB), urethane foam, polystyrene foam (EPS), extruded foam. Means an embankment made of polystyrene. Furthermore, “linkage” refers to linkage between a net member and a lightweight embankment, for example, if the tensile load acting on the net member during subsidence is transmitted to the lightweight embankment layer. It is also possible to link them by laying a net member directly or at an interval above the lightweight embankment layer.

  In this first level difference elimination structure, the light weight embankment layer protrudes outward from the structure and is embedded in the substantially horizontal direction below the roadbed, so the load on the outside of the structure is reduced, and the light weight is reduced. The stress applied to the soft ground below the embankment layer can be reduced, and uneven settlement between the light-weight embankment layer and the structure is prevented. In addition, since the net member linked to the lightweight embankment layer extends outward from the light embankment layer and is embedded in the horizontal direction under the roadbed, it is unevenly settled between the lightweight embankment layer and the soft ground outside it. The net member sinks integrally with the soft ground outside the lightweight embankment layer and pulls the lightweight embankment layer diagonally downward, so that the loading load on the net member is reduced to the soft ground below the light embankment layer and the net member. Evenly distributed, it is absorbed so that the gradient of the road surface does not increase.

  For this reason, the road surface on the upper side of the lightweight embankment layer in the structure and the vicinity thereof is substantially flat with almost no uneven settlement, and the road surface on the upper side of the net embankment and the lighter embankment layer in the vicinity thereof is gradually moved toward the structure side. As the slope rises in a curved line, it is possible to effectively prevent the occurrence of road level differences and cracks due to unequal subsidence, as well as to feel a strong impact from the road surface when the vehicle is running and to shorten the viewing distance. It can effectively prevent the road from deteriorating. Moreover, because the lightweight embankment layer and net members are lightweight, workability is good, and because the sinking speed is adjusted by using the lightweight embankment layer and net member together, compared to the case where the sinking speed is adjusted only with the lightweight embankment layer. This reduces the material cost. In addition, since it is not necessary to perform any processing on the structure, it is possible to employ this step eliminating structure when repairing an existing road, not to mention a new road.

The second road level difference elimination structure according to the present invention is a road level difference elimination structure on a soft ground in which a structure is embedded transversely to the road, and a lightweight embankment on the lower side of the roadbed above the structure. A layer is embedded in a substantially horizontal direction, and a net member linked to the lightweight embankment layer is projected outwardly from the lightweight embankment layer at a site where the soft ground on the outside of the lightweight embankment sinks unequally, and substantially below the roadbed. It is buried horizontally.

  In this second level difference elimination structure, since the lightweight embankment layer is provided on the upper side of the structure, the impact load acting on the road surface when a large truck passes is absorbed by the lightweight embankment layer, and the impact load The structure can be protected from. In addition, as with the first step elimination structure, it is possible to effectively prevent cracks and steps from being formed on the road, to prevent the road from degrading due to a large gradient, and only with a lightweight embankment layer. Compared to the case of construction, the material cost is low, and it is possible to employ this step elimination structure when repairing an existing road, not to mention a new road.

As described above, the lightweight embankment layer means an embankment layer having a unit volume mass of 1.1 t / m ³ or less. Specifically, the light-weight embankment (FCB), the foam bead-mixed lightweight soil, the urethane foam, This means an embankment layer made of expanded polystyrene (EPS), extruded polystyrene foam, etc., but it reduces the load on the outside of the structure and reduces the stress applied to the soft ground below the light embankment as much as possible. In order to prevent uneven settlement between the layer and the structure, it is preferable that the unit volume mass is set to 0.1 t / m ³ or less, and especially those constructed using a plurality of foamed resin blocks made of foamed polystyrene. It is suitable because of its excellent properties.

  In addition, the lightweight embankment layer can be set to a uniform thickness, but in order to reduce the earth pressure on the structure, it can be set thicker stepwise or continuously as it approaches the structure side. it can.

  The linkage of the net member to the lightweight embankment layer is performed by sandwiching the net member between the lightweight embankment layer and the roadbed disposed on the upper side in the first and second step elimination structures, but as other structures The net member can also be realized by integrating it with a lightweight embankment layer. For example, a light weight embankment is provided so that a concrete layer is provided on the upper side of the light weight embankment layer and the net member does not fall off the light weight embankment layer with this concrete layer. The layer and the net member can be integrated.

  Specifically, a net member is embedded in the concrete layer, or the concrete layer is formed of a precast concrete plate, and the net member is sandwiched between the concrete layer and the lightweight embankment layer. To embed a net member in a concrete layer, construct a form along the outer edge of the lightweight embankment layer, place the end of the net member on this formwork, and place the concrete into the concrete. The net member can be integrated with the lightweight embankment layer by burying construction. Moreover, when using a precast concrete board, after laying a net member on a lightweight embankment layer, laying a precast concrete board on it, sandwiching a net member between a lightweight embankment layer and a precast concrete board, Using the weight of the precast concrete board and the roadbed to prevent the net member from falling off the lightweight embankment layer, and connecting the precast concrete board to the precast concrete board using a special metal fitting, the net member is integrated with the lightweight embankment layer. can do.

  When the net members are extended from the lightweight embankment layer to both sides, it is possible to configure the net members on both sides as separate members, but the deflection of the light embankment layer and the net member during subsidence becomes even smoother. In order to change, a single continuous net member can be projected from the lightweight embankment layer to both outer sides and embedded in a substantially horizontal direction below the roadbed.

  The net member can be provided on the upper side of the lightweight embankment layer, or can be provided on both upper and lower sides. When it is provided on both the upper and lower sides, the backfill soil arranged between the upper and lower net members is integrated with the lightweight embankment layer by the net members, so the gradient change of the road surface due to unequal subsidence becomes more gradual, It is possible to reduce road surface unevenness more effectively and maintain road functions for a longer period of time.

  As the net member, a geotextile, a geogrid, or a combination of both can be suitably used.

  The net member is strongly pressed against the lightweight embankment layer at the outer edge of the lightweight embankment layer, and the net member may bite into the lighter embankment layer. It is also preferable to provide a reinforcing member that prevents the bite from entering.

  According to the first and second road leveling structure according to the present invention, while preventing a decrease in road function due to an increase in gradient, there is no level difference or cracking on the road on the soft ground in which the structure is embedded. It is possible to fundamentally eliminate what occurs due to equal settlement. Moreover, compared with the case where it comprises only a lightweight embankment layer, material cost becomes cheap and it becomes possible to construct at low cost. Further, it goes without saying that there are no new roads, and this level difference elimination structure can be adopted when repairing existing roads.

  Further, in the second road leveling structure, the impact load acting on the road surface when a large truck passes can be absorbed by the lightweight embankment layer and the structure can be protected from the impact load.

When the unit volume mass of the lightweight embankment layer is set to 0.1 t / m ³ or less, the load on the outside of the structure is reduced, and the stress applied to the soft ground below the lightweight embankment layer is reduced as much as possible. It is possible to effectively prevent uneven settlement between the embankment layer and the structure.

  When the lightweight embankment layer is composed of a plurality of foamed resin blocks, it is possible to construct the lightweight embankment layer easily and efficiently by a simple operation of installing the foamed resin block at the construction position of the lightweight embankment layer.

  If the thickness of the lightweight embankment layer is set to be increased stepwise or continuously as it approaches the structure side, the earth pressure on the structure can be reduced.

  When the net member is integrated with the lightweight embankment layer, the load acting on the net member during subsidence can be reliably transmitted to the lightweight embankment layer.

  When a concrete layer is provided on the upper side of the lightweight embankment layer and the lightweight embankment layer and the net member are integrated with the concrete layer, the bonding strength between the lightweight embankment layer and the net member can be further increased. In addition, if such a concrete layer is provided on the entire upper surface of the lightweight embankment layer, the concrete layer can connect a plurality of foamed resin blocks constituting the lightweight embankment layer to each other, and the impact load during traveling of a truck or the like can be reduced. Since it can disperse | distribute uniformly to a lightweight embankment layer by a layer, the function as a roadbed surface can be improved further.

  When embedding a net member in a concrete layer, work such as constructing a formwork at the site is required, but since the placed concrete also enters the net of the net member, the concrete layer and the net member are It can be firmly bonded, and the lightweight embankment layer and the concrete layer are also fully joined using the entire contact surface with the lightweight embankment layer, so the lightweight embankment layer and the net member are firmly integrated. can do.

  When the concrete layer is made of precast concrete board and the net member is sandwiched between the concrete layer and the lightweight embankment layer, construction work such as formwork at the site is not required, workability can be greatly improved, construction period shortening and traffic regulation Time can be shortened.

  If the continuous net members are projected from the lightweight embankment layer to the outside and embedded in the horizontal direction under the roadbed, the deflection of the light embankment layer and net member during subsidence can be changed more smoothly. Further, it is possible to more effectively prevent a step or a crack from being generated due to uneven settlement on a road on a soft ground in which a structure is embedded.

  When the net member is provided only on the upper side of the light-weight embankment layer, it is not necessary to dig deep into the soft ground at the position where the net member is laid, so that workability can be improved.

  In addition, when net members are provided on both upper and lower sides of the lightweight embankment layer, it is necessary to dig up the soft ground to the lower end level of the lightweight embankment layer even at the position where the net member is laid, but there is no backfill soil arranged between the net members. Because it is integrated with the lightweight embankment layer by the net member, the gradient change of the road surface due to unequal subsidence becomes more gradual, and the unequal subsidence of the road surface can be reduced more effectively and the road function can be maintained for a longer period of time. .

  When the net member is a geotextile or a geogrid or a combination of both, it is preferable because the soil has a strong binding force, can be reinforced with strong ground, and can be easily obtained.

  If a reinforcing member for preventing the net member from biting in is provided at the outer end portion of the light weight embankment layer, damage to the light weight embankment layer and the net member due to the bite of the net member can be prevented. In addition, since the load acting on the net member can be transmitted to the lightweight embankment layer without waste, it is possible to more effectively prevent road surface steps and cracks.

  Embodiments of the present invention will be described below with reference to the drawings.

  2 and FIG. 3, the level difference elimination structure 1 includes a lightweight embankment layer 6 composed of a plurality of foamed resin blocks 5 on a road 4 on a soft ground 3 in which a structure 2 is embedded in a transverse shape. The net member 8 that projects to both sides in the longitudinal direction is provided in a substantially horizontal direction, and the net member 8 that is linked to the lightweight embankment layer 6 projects from the lightweight embankment layer 6 to the outside in the longitudinal direction of the road 4 and is provided in a substantially horizontal direction. A concrete layer 9 is provided in a laminated form on the upper side, a lightweight embankment layer 6 and a concrete layer 9 and a net member 8 are respectively buried below the roadbed 7 and a pavement 10 made of asphalt is applied on the upper side. .

  The structure 2 includes any shape such as a circular cross section or a square cross section for electricity, telephone, gas, water and sewage, etc., a joint groove of any size, underground pipes, underground tunnels such as railways, etc. Although it is mentioned, the present invention can be applied to other structures.

  The length of the lightweight embankment layer 6 and the net member 8 with respect to the length direction of the structure 2 is set to be the same as or slightly longer than the width of the road 4. Further, the overhang length L1 of the light weight embankment layer 6 to the outside of the structure 2 is a distance obtained by adding the width H of the structure 2 to twice the overhang length L1 of the light weight embankment layer 6 in the level section in FIG. The extension length L2 of the net member 8 that conforms to L and extends outward from the lightweight embankment layer 6 is set so as to conform to the rubbed section S in FIG. Specifically, the design speed of the road 4, the total length or axle distance of the vehicle, the width H of the structure 2, and rubbing so as not to feel a strong impact from the road surface 12 when the vehicle is traveling or to shorten the visual distance. For example, when the design speed of the road 4 is 40 km / h, the width H of the structure 2 is 2 m, the total length of the vehicle is 12 m, and the axle distance is 6.5 m, the weight is set in consideration of the gradient in the section S. The overhang length L1 of the embankment layer 6 is set to 4 m, the overhang length L2 of the net member 8 is set to 15 m, and the maximum gradient of the road surface 12 is set to 3.0% or less.

  The light weight embankment layer 6 is constructed by installing a necessary number of foamed resin blocks 5 in a matrix shape or a staggered shape in a foam construction hole 11 formed by digging down the soft ground 3 on both sides of the structure 2. The upper surface of the lightweight embankment layer 6 is disposed at a position one step lower than the upper surface of the structure 2, and the upper surface of the concrete layer 9 is the upper surface of the structure 2 in a state where the concrete layer 9 is constructed on the upper side of the lightweight embankment layer 6. It is set to be approximately the same height.

  For example, a foamed resin block 5 having a length of 2 m, a width of 1 m, and a height of 0.5 m, and a weight of 12 to 30 kg per piece can be suitably used because it is easy to carry and is excellent in construction work. The size and weight of the resin block 5 can be arbitrarily set. The foamed resin block 5 may be made of a foamed material made of a synthetic resin such as polystyrene, polyurethane, or polyvinyl chloride.

  Adjacent foamed resin blocks 5 can be integrated with an adhesive or the like, but in this embodiment, a connecting fitting (not shown) formed by projecting a claw portion on the lower surface of the plate member is used as the foamed resin block 5. The nail | claw part is stabbed in the surface of this, and it connects by attaching a connection metal fitting over the foamed resin block 5 which adjoins. The foamed resin block 5 on the structure 2 side is closely arranged on the side surface of the structure 2 without using an adhesive or the like, but can be fixed integrally with an adhesive or a metal fitting.

In this embodiment, the light-weight embankment layer 6 is formed using a plurality of foamed resin blocks 5, but any shape and any material can be used as long as the unit volume mass is 1.1 t / m ³ or less. For example, it is also possible to configure with foam mixed lightweight soil (FCB), urethane foam, polystyrene foam (EPS), extruded foam polystyrene, and the like. In particular, in order to reduce the loading load on both sides of the structure 2 as much as possible, the unit volume mass of the lightweight embankment layer 6 is preferably set to 0.1 t / m ³ or less, and the foamed resin block 5 made of foamed polystyrene as described above. Is preferable because the unit volume mass can be set to 0.1 t / m ³ or less and the workability is excellent.

The net member 8 can be made of synthetic resin, metal, or a composite material thereof, but among the geotextiles widely used in civil engineering and other applications, a geogrid excellent in tensile strength is preferably used. it can. Geogrid is for the synthetic polymer material such as polypropylene or polyamide a material, the strength is about 5kN / m~200kN / m, the weight is ^{50g / m 2 ~1000g / m 2} , weight Despite this, it has characteristics such as toughness and high tension. The scale is preferably 5 mm to 200 mm, for example, and the thickness is about 1.0 mm to 8.0 mm, for example.

  The concrete layer 9 is formed by laying a precast concrete plate 9a having a well-known configuration on the upper side of the lightweight embankment layer 6. A concrete layer 9 having a required thickness can be formed by casting concrete. However, the concrete layer 9 is not necessarily essential, and can be omitted on the road 4 where the load acting on the lightweight embankment layer 6 is small, such as a sidewalk.

  The net member 8 is fixed to the lightweight embankment layer 6 when the concrete layer 9 is formed by laying the precast concrete plate 9a, and one end of the net member 8 is overlapped on the upper side of the light embankment layer 6 by a certain range L3. In this state, by laying the precast concrete plate 9 a, the net member 8 can be sandwiched between the precast concrete plate 9 a and the lightweight embankment layer 6, and the net member 8 can be integrated with the lightweight embankment layer 6. In addition, when the concrete layer 9 is formed by placing concrete, the end of the net member 8 is overlapped by a certain width L3 in the mold constructed along the outer edge of the lightweight embankment layer 6. By placing concrete in the mold, one end of the net member 8 can be embedded in the concrete layer 9 and the net member 8 can be integrated with the lightweight embankment layer 6.

  The overlapping width L3 of the net member 8 with respect to the light weight embankment layer 6 is sufficient for the bonding strength between the light weight embankment layer 6 and the net member 8, particularly the bond strength against the skidding of the net member 8 to the light weight embankment layer 6 to the outside. Any width that can be secured can be set. However, the net member 8 can be integrated with the lightweight embankment layer 6 using a metal fitting or the like, or the net member 8 is wound around the foamed resin block 5 to integrate the net member 8 with the light embankment layer 6. You can also. For example, as shown in FIG. 4, as the precast concrete plate 9a, L-shaped anchors 15 are embedded and fixed in the width direction of the road 4 at regular intervals, and the net member 8 is in a state where the reinforcing bars 16 are arranged at the ends. By attaching the fixing bar 17 by fitting the folded portions to each other, the reinforcing bar 16 is fixed to the end of the net member, and the reinforcing bar 16 fixed to the end of the net member is engaged with the L-shaped anchor 15. The net member 8 can also be indirectly fixed to the lightweight embankment layer 6 through the precast concrete plate 9a.

  Reinforcing members 13 made of a metal plate, a synthetic resin plate, or the like are provided along the corners of the lightweight embankment layer 6 on the outer end upper portion of the lightweight embankment layer 6. Biting into the corners is prevented. However, the reinforcing member 13 can be omitted.

  Next, a road repair method using the level difference elimination structure 1 will be described.

  First, after removing the roadbed 7 on the upper side of the structure 2 and on both sides of the structure 2 in the construction range of the step elimination structure 1, the soft ground 3 in the construction range of the lightweight embankment layer 6 is dug down, and the foam construction hole 11. Form.

  Next, the foamed resin block 5 is provided in the foam construction hole 11 without a gap, and the adjacent foamed resin blocks 5 are connected by a connecting fitting (not shown) to form the lightweight embankment layer 6.

  Next, the net member 8 is laid in a substantially horizontal direction on the soft ground 3 outside the lightweight embankment layer 6 with the end of the net member 8 superimposed on the upper surface of the light-weight embankment layer 6 near the outer end. At the same time, a precast concrete plate 9 a is laid on the entire top surface of the foamed resin block 5 to form the concrete layer 9 on the lightweight embankment layer 6, and the end of the net member 8 is sandwiched between the concrete layer 9 and the foamed resin block 5. Fix it. When the concrete layer 9 is formed by placing concrete, the outer edge of the lightweight embankment layer 6 is laid along the outer edge of the lightweight embankment layer 6 with the end of the net member 8 laid on the upper surface of the vicinity of the outer edge of the lightweight embankment layer 6. The mold is constructed, concrete is placed in the mold, the concrete layer 9 is integrally formed on the upper side of the lightweight embankment layer 6, and one end portion is embedded in the concrete layer 9 to attach the net member 8. It will be integrated into the lightweight embankment layer 6.

  Thus, with the foamed resin layer, the concrete layer 9 and the net member 8 being constructed, the roadbed 7 is constructed, the pavement 10 is applied, and the repair is completed.

  In the road 4 in which the level difference eliminating structure 1 is constructed in this way, the lightweight embankment layer 6 made of the lightweight foamed resin block 5 protrudes outward from the structure 2 and is buried substantially horizontally in the lower side of the roadbed 7. Therefore, it is possible to reduce the load applied to the outside of the structure 2 and to reduce the stress applied to the soft ground 3 below the lightweight embankment layer 6. Equal subsidence is prevented. Moreover, since the net member 8 integrated with the lightweight embankment layer 6 protrudes outward from the light embankment layer 6 and is embedded in a substantially horizontal direction below the roadbed 7, the light embankment layer 6 and the soft ground on the outside thereof are embedded. 3, the net member 8 sinks integrally with the soft ground 3 outside the lightweight embankment layer 6, and pulls the lightweight embankment layer 6 diagonally downward, thereby reducing the load applied to the net member 8. It can be absorbed evenly on the soft ground 3 below the lightweight embankment layer 6 and the net member 8 so that the gradient of the road surface 12 does not increase. For this reason, the road surface 12 is maintained substantially horizontal in the vicinity of the upper side of the structure 2, and a gentle upward slope toward the structure 2 in the vicinity of the outer edge of the lightweight embankment layer 6 and the upper side of the net member 8. In order to prevent the occurrence of steps and cracks due to a large change in gradient, the impact from the road surface when the vehicle is running is reduced, and the viewing distance is shortened. It is prevented.

  Next, another embodiment in which the configuration of the level difference eliminating structure 1 is partially changed will be described. The same members as those in the above embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

(1) Instead of the light-weight embankment layer 6 having a uniform thickness as in the step elimination structure 1A shown in FIG. 5, the thickness gradually increases as the structure 2 is approached. It is also possible to provide a lightweight embankment layer 6A in which the number of stacked steps of the foamed resin block 5 is set. In this case, the earth pressure on both sides of the structure 2 can be reduced as much as possible. In the present invention, since the lightweight embankment layer 6A is composed of the foamed resin block 5, the thickness is gradually increased as the structure 2 is approached, but the foamed resin block 5 is cut off. It can also be set continuously thick. Further, when the lightweight embankment layer is composed of granular embankments, the thickness can be increased continuously or stepwise as the structure 2 is approached.

(2) In the above embodiment, the two net members 8 are provided so as to protrude outward from the lightweight embankment layer 6, but the single net member 8B is a concrete layer as in the step elimination structure 1B shown in FIG. 9 and the entire upper surface of the structure 2 are provided so as to project from the concrete layer 9 to both sides, and the net member 8B is not fixed to the lightweight embankment layer 6 by the concrete layer 9 but The bond strength can also be increased. In particular, when the concrete layer 9 is not provided, it is preferable because the bonding strength between the lightweight embankment layer 6 and the net member 8B can be increased. Note that the net member 8B does not necessarily need to be in close contact with the lightweight embankment layer 6 or the concrete layer 9 as long as the tensile load acting on the net member 8B when settling is received by the lightweight embankment layer 6. It is also possible to provide it in a buried manner in the roadbed 7 above the embankment layer 6 and the concrete layer 9.

(3) A net member 20 extending outward from the lower surface of the lightweight embankment layer 6 is provided substantially parallel to the net member 8 on the upper side of the light embankment layer 6 as in the step elimination structure 1C shown in FIG. The net member 20 can be integrated with the light weight embankment layer 6 by sandwiching the portion between the light weight embankment layer 6 and the soft ground 3 layer below it. In this case, it is necessary to dig up the level difference eliminating structure 1C to the same level as the lower surface of the lightweight embankment layer 6 even at the construction position of the net members 8 and 20, but the upper and lower net members 8 and 20 are buried between them. Since the return soil 21 is integrated with the lightweight embankment layer 6, uneven settlement can be prevented more effectively.

(4) It is also possible to form a lightweight embankment layer 6D by stacking a plurality of foamed resin blocks 5 up and down as in the step elimination structure 1D shown in FIG. In this case, the net member 22 projecting in the substantially horizontal direction from the middle portion in the height direction of the lightweight embankment layer 6D is embedded under the net member 8, and the end portion of the net member 22 is vertically foamed. The net member 22 can be integrated with the lightweight embankment layer 6 </ b> D by being sandwiched between the resin blocks 5.

(5) In this embodiment, as shown in FIG. 2, the present invention is applied to the road 4 in which the structure 2 is embedded so that the upper surface is substantially the same height as the boundary surface P between the soft ground 3 and the roadbed 7. However, the present invention can also be applied to a road in which the structure 2 is embedded at an arbitrary depth below the boundary surface P. In this case, a light-weight embankment layer 6E in which the foamed resin block 5 is disposed also on the upper side of the structure 2 is constructed as in the step elimination structure 1E shown in FIG. The lightweight embankment layer 6E may be provided in close contact with the upper surface of the structure 2 or may be provided on the upper side of the structure 2 with an interval.

  In addition, this level | step difference elimination structure 1A-1E can be applied not only to the repair of the existing road but also to the case where a road is newly established, and also to the case where a structure is embedded in an existing road in a transverse manner. Although it is particularly preferable to apply to a roadway, it can also be applied to a sidewalk. Furthermore, the structure which combined level | step difference elimination structure 1A-1E is also employable.

  In the present embodiment, the present invention is applied to the road 4 on the soft ground 3 in which the structure 2 is embedded so as to cross the road 4, but the soft ground in which the structure 2 is embedded so as to run through the road 4. The present invention can be similarly applied to roads 3. However, in this case, the light weight embankment layer 6 and the net member 8 are laid out outside the structure 2, that is, in the width direction of the road 4.

  Further, the structure 2 includes an abutment 31 such as a bridge 30 provided in the middle of the road 4 as shown in FIG. 10 in addition to the joint grooves and the underground pipes as described above. In such a level difference elimination structure 32 on the road 4, as in the level difference elimination structure 1, a light-weight embankment layer 6 composed of a plurality of foamed resin blocks 5 is projected from the upper end of the abutment 31 toward the soft ground 3 side in a substantially horizontal direction. The net member 8 integrated with the lightweight embankment layer 6 is projected from the lightweight embankment layer 6 to the outside in the longitudinal direction of the road 4 and provided in a substantially horizontal direction, and the concrete layer 9 is laminated on the upper side of the lightweight embankment layer 6. It can be constructed by providing and embedding the light weight embankment layer 6 and the concrete layer 9 and the net member 8 below the roadbed 7 and applying asphalt pavement 10 on the upper side thereof.

  In such a level difference elimination structure 32, as in the level difference elimination structure 1, the functional deterioration of the road 4 due to uneven settlement is effectively prevented by the lightweight embankment layer 6, the net member 8, and the concrete layer 9. Can do.

Schematic explanatory diagram of the step elimination structure Longitudinal longitudinal sectional view of the road where the level difference elimination structure is constructed Longitudinal cross section near the outer edge of the lightweight embankment layer on the road where the level difference elimination structure is constructed Explanatory drawing of fixing method of net member to lightweight embankment layer Longitudinal cross-sectional view of a road with a step-relief structure of another configuration Longitudinal cross-sectional view of a road with a step-relief structure of another configuration Longitudinal cross-sectional view of a road with a step-relief structure of another configuration Longitudinal cross-sectional view of a road with a step-relief structure of another configuration Longitudinal cross-sectional view of a road with a step-relief structure of another configuration Longitudinal longitudinal section of a road with a step-removal structure near the abutment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Level difference elimination structure 2 Structure 3 Soft ground 4 Road 5 Foamed resin block 6 Lightweight embankment layer 7 Roadbed 8 Net member 9 Concrete layer 9a Precast concrete board 10 Pavement 11 Foam construction hole 12 Road surface 13 Reinforcement member 15 L-type anchor 16 Reinforcing bar 17 A fixed bar 1A Step elimination structure 6A Lightweight embankment layer 1B Step elimination structure 8B Net member 1C Step elimination structure 20 Net member 21 Backfill soil 1D Step elimination structure 6D Lightweight embankment layer 22 Net member 1E Step elimination structure 6E Lightweight embankment layer 30 Bridge 31 Abutment 32 Level difference elimination structure

Claims (14)

In the road leveling elimination structure on the soft ground where the structure is buried or installed transversely to the road,
A light-weight embankment layer is embedded in the horizontal direction under the roadbed by projecting outward from the structure,
In the part where the soft ground on the outside of the lightweight embankment sinks unevenly, a net member linked to the lightweight embankment layer is projected from the lightweight embankment layer to the outside and embedded in a substantially horizontal direction below the roadbed,
A road leveling structure characterized by that. In the road leveling structure on the soft ground where the structure is embedded transversely to the road,
On the upper side of the structure, a lightweight embankment layer is embedded in a substantially horizontal direction below the roadbed,
In the part where the soft ground on the outside of the lightweight embankment sinks unevenly, a net member linked to the lightweight embankment layer is projected from the lightweight embankment layer to the outside and embedded in a substantially horizontal direction below the roadbed,
A road leveling structure characterized by that. The level | step difference elimination structure of the road of Claim 1 or 2 which set the unit volume mass of the said lightweight embankment layer to 0.1 t / m < ³ > or less.   The level | step difference elimination structure of the road of any one of Claims 1-3 which comprised the said lightweight embankment layer with the several foamed resin block.   The road level difference eliminating structure according to any one of claims 1 to 4, wherein the thickness of the lightweight embankment layer is set to be thicker stepwise or continuously as it approaches the structure side.   The road level difference eliminating structure according to any one of claims 1 to 5, wherein the net member is integrated with a lightweight embankment layer.   The level | step difference elimination structure of the road of any one of Claims 1-6 which provided the concrete layer above the said lightweight embankment layer, and integrated the lightweight embankment layer and the net member with the concrete layer.   The road level difference eliminating structure according to claim 7, wherein a net member is embedded in the concrete layer.   The road level difference eliminating structure according to claim 7, wherein the concrete layer is made of a precast concrete plate, and a net member is sandwiched between the concrete layer and the lightweight embankment layer.   The road level difference eliminating structure according to any one of claims 1 to 9, wherein continuously connected net members are extended from the light weight embankment layer to both outer sides and embedded in a substantially horizontal direction below the roadbed.   The road level difference eliminating structure according to any one of claims 1 to 10, wherein a net member is provided above the lightweight embankment layer.   The road level difference eliminating structure according to any one of claims 1 to 11, wherein net members are provided on both upper and lower sides of the lightweight embankment layer.   The road level difference eliminating structure according to any one of claims 1 to 12, wherein the net member is a geotextile, a geogrid, or a combination of both. The road level difference eliminating structure according to any one of claims 1 to 13, wherein a reinforcing member for preventing biting of the net member is provided at an outer end portion of the lightweight embankment layer.

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