JP7077907B2 - Abutment reinforcement structure - Google Patents

Description

The present invention relates to an abutment reinforcing structure, and more particularly to an abutment reinforcing structure whose back surface is adjacent to an embankment.

Where the back of the abutment is adjacent to the embankment, for example, the earth pressure of the embankment can cause the abutment to tilt or slide, or the wings built on the side of the abutment to deform or collapse when an earthquake load is applied. There is sex. In such a case, if the embankment flows out or sinks, the transportation of the track or road laid on the embankment will be hindered.

Conventionally, in order to reinforce the abutment in such a place, a method of penetrating a ground anchor from the front side of the abutment or improving the ground of the embankment has been used. However, it is difficult to construct the ground anchor when the space for construction cannot be secured on the front side of the abutment, and it is difficult to construct the ground anchor during operation because the ground improvement involves work such as digging up the embankment.

In view of these points, Patent Document 1 proposes a reinforcing structure for an abutment in which an improved embankment composed of a plurality of columnar bodies is provided in the vertical direction in the embankment located on the back surface side of the abutment. In the technique described in Patent Document 1, a plurality of embankment improvement bodies are arranged in a wavy line formed by a straight line in a state of being connected in a wall shape adjacent to each other in a direction intersecting the bridge axis direction.

In the technique described in Patent Document 1 above, the earth pressure wave at the time of the occurrence of an earthquake is divided by the wall-shaped embankment improver and becomes smaller, so that the earth pressure applied to the back surface of the abutment can be dispersed. Further, since the vibration of the embankment shaken by the earthquake is dampened by the friction between the embankment and the embankment improver, the embankment pressure applied to the back surface of the abutment when the earthquake occurs can be reduced.

Japanese Unexamined Patent Publication No. 2016-148196

However, in the case of the technique described in Patent Document 1 above, the embankment improved body is a soil cement formed by stirring the embankment with cement milk while excavating the embankment with a drilling stirring drill, and therefore is strong against a compressive load. Is vulnerable to tensile loads. In addition, it is not easy to integrate the embankment improvement body formed of soil cement with the abutment. Therefore, for example, when a tensile load is applied to the embankment improved body at the time of an earthquake, the embankment can flow out from the part where the connecting structure of the embankment improved body is broken or from the gap between the embankment improved body and the abutment. There is sex.

Therefore, an object of the present invention is to provide a reinforcing structure for an abutment that is easy to construct and can withstand a tensile load.

According to one aspect of the invention, the abutment reinforcement structure whose back surface is adjacent to the extension end of the embankment consists of a plurality of steel sheet piles connected to each other at the widthwise end corresponding to the extension direction of the embankment. It is equipped with a steel sheet pile wall that supports the earth pressure of the embankment on at least one side. Of the plurality of steel sheet piles, one end in the width direction of the steel sheet pile adjacent to the abutment is connected to the abutment.

The abutment reinforcement structure may further include connecting members that connect the heads of the plurality of steel sheet piles to each other.

In the above abutment reinforcement structure, one end in the width direction of the steel sheet pile adjacent to the abutment may be connected to the side surface or the back surface of the abutment.

In the above abutment reinforcement structure, the steel sheet pile wall may be arranged at a position that does not overlap in the horizontal direction with respect to the track or road laid in the extension direction of the embankment.

In the reinforcement structure of the abutment, at least a part of the plurality of steel sheet piles may have through holes formed in a direction orthogonal to the width direction.

In the abutment reinforcement structure described above, the plurality of steel sheet piles are a first steel sheet pile to be driven to a first depth and a second steel to be driven to a second depth deeper than the first depth. It may include a sheet pile.

The abutment reinforcement structure described above further comprises a closing member that is joined to at least a portion of the steel sheet piles at a position that will be in the ground after casting and forms a closing region in a cross section orthogonal to the longitudinal direction of the steel sheet piles. May be good.

The reinforcement structure of the above abutment is joined at a position where at least a part of a plurality of steel sheet piles becomes an underground part after being placed, and in a cross section orthogonal to the longitudinal direction of the steel sheet piles, a direction substantially orthogonal to the width direction of the steel sheet piles. A protruding member may be further provided.

Since the above-mentioned abutment reinforcement structure can be constructed by placing steel sheet piles, it is easy to construct even while the track or road laid on the embankment is in service, for example. In addition, since the steel sheet pile is made of steel, it is strong against tensile load, and since the steel sheet pile joint is designed on the assumption that tensile stress acts, the steel sheet pile wall as a whole can sufficiently withstand the tensile load. It is possible. By connecting such a steel sheet pile wall to the abutment, the earth pressure acting on the back surface of the abutment can be reduced, and the displacement of the abutment due to the earth pressure can be suppressed.

It is a side view of the reinforcement structure of the abutment which concerns on 1st Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 1st Embodiment of this invention. It is a top view which shows the arrangement example of the orbit in 1st Embodiment of this invention. It is a top view which shows the arrangement example of the orbit in 1st Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 2nd Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 2nd Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 3rd Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 3rd Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 4th Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 4th Embodiment of this invention. It is a figure which shows the example of the structure which connects the steel sheet pile by using the cavity formed in the back surface of the abutment. It is a figure which shows the example of the structure which connects the steel sheet pile by using the cavity formed in the back surface of the abutment. It is a figure which shows the example of the structure which connects the steel sheet pile by using the cavity formed in the back surface of the abutment. It is a figure which shows the example of the structure which connects the steel sheet pile by using the cavity formed in the back surface of the abutment. It is a top view of the reinforcement structure of the abutment which concerns on 5th Embodiment of this invention. It is a top view of the reinforcement structure of the abutment which concerns on 5th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 6th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 6th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 6th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 7th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 7th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 7th Embodiment of this invention. It is a side view of the reinforcement structure of the abutment which concerns on 7th Embodiment of this invention. It is a figure which shows the example which joins the projecting member to a steel sheet pile in embodiment of this invention.

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, and duplicate description will be omitted.

1A and 1B are side views and plan views of the abutment reinforcement structure according to the first embodiment of the present invention. 1A and 1B show IA-IA and IB-IB lines showing the relationship between the figures. In the plan views after FIG. 1B, the bridge girder B and the water surface are not shown. As shown in FIGS. 1A and 1B, the reinforcing structure 3 of the abutment 2 that supports the bridge girder B and has the back surface 2A adjacent to the end in the extension direction (x direction in the figure) of the embankment 1 is a steel sheet pile wall 4. including. The steel sheet pile wall 4 is composed of a plurality of hat-shaped steel sheet piles 5 arranged so that the width direction coincides with the extension direction of the embankment 1. A joint (not shown) is formed at the widthwise end of each steel sheet pile 5, and the plurality of steel sheet piles 5 are connected to each other at the widthwise end by fitting the joint to each other. .. In the illustrated example, each steel sheet pile 5 is driven into the embankment 1 to a predetermined depth, whereby the steel sheet pile wall 4 supports the earth pressure of the embankment 1 on both sides.

Although the abutment 2 is shown in FIG. 1A with an L-shaped cross section, the abutment 2 is not limited to this example and may have, for example, an inverted T-shaped cross section. Further, the abutment 2 may be a pile foundation (including a wooden pile). Further, in the illustrated example, the depth at which the steel sheet pile 5 is placed on the embankment 1 substantially coincides with the bottom depth of the abutment 2, but the present invention is not limited to this, and the steel sheet pile 5 is the bottom surface of the abutment 2. It may be placed shallower than, or it may be placed deeper than the bottom surface of the abutment 2.

In the example shown in FIG. 1A, a through hole 5B is formed in the steel sheet pile 5 in a direction orthogonal to the width direction. By forming the through hole 5B, for example, water permeability inside the embankment 1 can be ensured. The through hole 5B may be formed in a part of the steel sheet piles 5, may be formed in all the steel sheet piles 5, or may not be formed, for example, if sufficient water permeability can be obtained in the vertical direction. good. By ensuring the permeability inside the embankment 1, the water level inside the embankment 1 is prevented from rising during rainfall, and the outflow of fine particles of soil that occurs when the water level drops after the water level rise is suppressed. be able to. Although the through hole 5B is not shown in the drawings after FIG. 1B, it is possible to form the through hole 5B in the same manner as in the example of FIG. 1A.

Here, in the present embodiment, of the plurality of steel sheet piles 5 constituting the steel sheet pile wall 4, one end of the steel sheet pile 5A adjacent to the abutment 2 in the width direction uses an anchor 6 to form a side surface 2B of the abutment 2. Is linked to. More specifically, for example, the arm portion formed at one end of the steel sheet pile 5A in the width direction may be directly connected to the side surface 2B of the abutment 2 by using the anchor 6. Alternatively, the steel sheet pile 5A is formed by attaching a joint member to the side surface 2B of the abutment 2 using the anchor 6 and fitting the joint formed at one end of the steel sheet pile 5A in the width direction to the joint member. It may be connected to the side surface 2B of the abutment 2.

As described above, in the present embodiment, the reinforcing structure 3 includes the steel sheet pile wall 4. Since the steel sheet pile 5 constituting the steel sheet pile wall 4 is made of a steel material, it is strong against a tensile load, and since the joint of the steel sheet pile 5 is designed on the premise that a tensile stress acts, the entire steel sheet pile wall 4 is formed. Even so, it can sufficiently withstand the tensile load in the width direction (x direction in the figure).

Further, in the present embodiment, the steel sheet pile 5A constituting the steel sheet pile wall 4 and adjacent to the abutment 2 is connected to the side surface 2B of the abutment 2. As a result, the earth pressure acting on the back surface 2A of the abutment 2 is reduced, and the displacement of the abutment 2 in the extension direction (x direction in the figure) of the embankment 1 due to the earth pressure is set in the width direction of the steel sheet pile 5 (in the figure). It can be suppressed by the shear resistance in the x direction) and the vertical bearing capacity. Further, it is possible to prevent the embankment 1 in the portion adjacent to the back surface 2A of the abutment 2 from flowing out from the gap between the abutment 2 and the steel sheet pile 5A.

2 and 3 are plan views showing an example of arrangement of trajectories according to the first embodiment of the present invention. In the example shown in FIG. 2, a single track T is laid on the embankment 1 in the extension direction of the embankment 1 (x direction in the figure), and in the example shown in FIG. 3, the double track T1 is laid in the same direction. T2 is laid. In these examples, the steel sheet pile wall 4 constituting the reinforcing structure 3 of the abutment 2 is arranged at positions that do not overlap in the horizontal direction (x direction and y direction in the figure) with respect to the track T or the tracks T1 and T2. There is. As a result, for example, even when the reinforcing structure 3 is subsequently constructed on the embankment 1 and the abutment 2 on which the track T or the tracks T1 and T2 have already been laid, the steel sheet pile 5 to be driven to construct the steel sheet pile wall 4 Does not interfere with the track T or the tracks T1 and T2, and the reinforcing structure 3 can be easily constructed even while the track T or the tracks T1 and T2 are in service.

Even when the track T or the tracks T1 and T2 have not been laid, the step of placing the steel sheet pile 5 is easier than, for example, a step of ground improvement or penetration of a ground anchor. Further, when the road is laid as in the above-mentioned track T or tracks T1 and T2, the construction of the reinforcing structure 3 becomes easy while the road is in service.

4A and 4B are side views and plan views of the abutment reinforcement structure according to the second embodiment of the present invention. 4A and 4B show the IVA-IVA and IVB-IVB lines showing the relationship between the figures. As a difference from the first embodiment described above, in the present embodiment, the reinforcing structure 3A of the abutment 2 is a concrete connecting member 7 that connects the heads of the plurality of steel sheet piles 5 constituting the steel sheet pile wall 4 to each other. Including further. Since the configuration of the present embodiment is the same as that of the first embodiment with respect to other points, duplicated description will be omitted.

The connecting member 7 is formed of, for example, cast-in-place concrete. Specifically, the connecting member 7 is constructed after all the steel sheet piles 5 have been placed on the embankment 1. In the present embodiment, the heads of the plurality of steel sheet piles 5 are connected to each other by the connecting member 7, for example, when the abutment 2 attempts to roll or tilt around the lower end position 2C on the front surface, in the vertical direction. It is possible to prevent the plurality of steel sheet piles 5 from sliding in the depth direction with each other due to the shearing force, and reliably transmit the vertical bearing capacity of the plurality of steel sheet piles 5 to the abutment 2 to suppress the displacement of the abutment 2. ..

5A and 5B are side views and plan views of the abutment reinforcement structure according to the third embodiment of the present invention. 5A and 5B show VA-VA and VB-VB lines showing the relationship between the figures. In FIG. 5B, the bridge girder B and the water surface are not shown. As a difference from the first embodiment described above, in the present embodiment, the reinforcing structure 3B of the abutment 2 is a steel connecting member 8 that connects the heads of a plurality of steel sheet piles 5 constituting the steel sheet pile wall 4 to each other. Including further. Since the configuration of the present embodiment is the same as that of the first embodiment with respect to other points, duplicated description will be omitted.

The connecting member 8 is connected to the head of each steel sheet pile 5 by welding or using a joining member such as a bolt. For example, the connecting member 8 is joined to each steel sheet pile 5 after all the steel sheet piles 5 have been placed. The connecting member 8 is not limited to the plate-shaped member as shown in the illustrated example, and steel materials having various shapes such as H-shaped steel, channel steel, and T-shaped steel can be used for the connecting member 8. Also in this embodiment, as in the second embodiment described above, the heads of the plurality of steel sheet piles 5 are connected to each other by the connecting member 8, so that the plurality of steel sheet piles 5 are deeply connected to each other by the shearing force in the vertical direction. It is possible to prevent sliding in the vertical direction and reliably transmit the vertical bearing capacity of the plurality of steel sheet piles 5 to the abutment 2 to suppress the displacement of the abutment 2. In the illustrated example, the connecting member 8 is arranged inside the steel sheet pile wall 4 when viewed in the width direction of the embankment 1 (y direction in the drawing), but the connecting member 8 is formed on the steel sheet pile wall 4. It may be arranged on the outside, or the connecting member 8 may be arranged on both the inside and the outside of the steel sheet pile wall 4.

6 and 7 are plan views of the abutment reinforcement structure according to the fourth embodiment of the present invention. 6 and 7 correspond to FIGS. 2 and 3 (first embodiment) described above, respectively. As a difference from the first embodiment, in the reinforcing structure 3C of the abutment 2 according to the present embodiment, among the plurality of steel sheet piles 5 constituting the steel sheet pile wall 4, the steel sheet pile 5A adjacent to the abutment 2 is in the width direction. One end is connected to the back surface 2A of the abutment 2 using the joint member 9. Since the configuration of the present embodiment is the same as that of the first embodiment with respect to other points, duplicated description will be omitted.

The joint member 9 is, for example, a member in which a joint portion is joined to flat steel by welding. The flat steel is connected to the back surface 2A of the abutment 2 by using an anchor, and the joint portion is fitted to the joint portion of the steel sheet pile 5A ( See also the relationship between the joint member 9G and the steel sheet pile 5A shown in FIG. 8C, which will be described later). By connecting the steel sheet pile 5A to the back surface 2A of the abutment 2 using the joint member 9, the earth pressure acting on the back surface 2A of the abutment 2 is reduced, and the extension direction of the embankment 1 (x direction in the figure). The point that the displacement of the abutment 2 in the above can be suppressed is the same as that of the first embodiment described above.

Further, in the present embodiment, in the portion adjacent to the back surface 2A of the abutment 2, the embankment 1 in the region sandwiched between the steel sheet pile walls 4 when viewed in the width direction of the embankment 1 (y direction in the figure) is formed. The outflow is prevented. The embankment 1 in the outer region of the steel sheet pile wall 4 has no effect of preventing outflow by the reinforcing structure 3C, but the track T is located in the region sandwiched between the steel sheet pile walls 4, so that the track T has a transport function. In terms of maintenance, the same effect as that of the first embodiment described above can be obtained.

Also in this embodiment, the steel sheet pile wall 4 is arranged at a position that does not overlap with the track T or the tracks T1 and T2 in the horizontal direction (x direction and y direction in the figure). Therefore, also in this embodiment, the steel sheet pile 5 cast to construct the steel sheet pile wall 4 does not interfere with the track T or the tracks T1 and T2, and the track T or the track T1 and T2 are in service. The reinforcing structure 3C can be easily constructed.

8A to 8D are views showing an example of a structure in which steel sheet piles are connected by using a cavity formed on the back surface of the abutment. In the example shown in FIG. 8A, a cavity 9A having a bulbous cross section including a connecting portion and a circular enlarged portion is formed on the back surface of the abutment 2. The steel sheet pile 5A is connected to the abutment 2 on the back surface by inserting the joint portion into the cavity 9A at the time of placing the steel sheet pile 5A and filling the cavity 9A with the mortar 9B after the placement. In the example shown in FIG. 8B, in addition to the configuration of the example of FIG. 8A, by fitting the reinforcing steel plate 9C having a C-shaped cross section on the inner surface of the cavity 9A, the cavity 9A is formed when a tensile stress is applied to the steel sheet pile 5A. Prevents the connection from deforming. In the example shown in FIG. 8C, a cavity 9D having a cross section including a connecting portion and a rectangular enlarged portion is formed on the back surface of the abutment 2. Inside the cavity 9D, a joint member 9G to which the flat steel 9E and the joint portion 9F are welded is arranged. When the steel sheet pile 5A is placed, the joint portion is fitted to the joint portion 9F of the joint member 9G, and after the placement, the cavity 9D is filled with the mortar 9B so that the steel sheet pile 5A is placed on the back surface of the abutment 2 via the joint member 9G. Be concatenated. In the example shown in FIG. 8D, the reinforcing steel plate 9C is fitted into the inner surface of the cavity 9A having a bulbous cross section as in the example of FIG. 8B, and the flat steel 9E is joined to the inside of the reinforcing steel plate 9C as in the example of FIG. A joint member 9G welded to the portion 9F is arranged. The flat steel 9E may be joined to the reinforcing steel plate 9C by, for example, welding.

In the above example, the cavities 9A and 9D may be formed over the entire length from the upper end to the lower end of the back surface of the abutment 2. In this case, regardless of the casting depth of the steel sheet pile 5A, the steel sheet pile 5A is fixed to the back surface of the abutment 2 by inserting the joint portion of the steel sheet pile 5A into the cavities 9A and 9D formed on the back surface of the abutment 2. Can be done. Alternatively, the cavities 9A and 9D may be formed in a part of the upper end side of the back surface of the abutment 2 and may not reach the lower end. In this example, when the casting depth of the steel sheet pile 5A exceeds the lengths of the cavities 9A and 9D, the joint portion of the steel sheet pile 5A is cut off at the portion exceeding the lengths of the cavities 9A and 9D. It is possible to prevent the steel sheet pile 5A and the abutment 2 from interfering with each other even in a portion where 9D is not formed.

9 and 10 are plan views of the abutment reinforcement structure according to the fifth embodiment of the present invention. 9 and 10 correspond to FIGS. 3 (first embodiment) and 7 (fourth embodiment) described above, respectively. The difference from the first and fourth embodiments is that the reinforcing structure 3D of the abutment 2 according to the present embodiment has double-track tracks T1 and T2 when viewed in the width direction of the embankment 1 (y direction in the figure). In addition to the steel sheet pile walls 4 arranged on both outer sides, the steel sheet pile wall 4D arranged between the tracks T1 and T2 of the double track is included. Since the configuration of the present embodiment is the same as that of the first or fourth embodiment with respect to other points, duplicated description will be omitted.

Like the steel sheet pile wall 4, the steel sheet pile wall 4D is composed of a plurality of steel sheet piles 5, and one end of the plurality of steel sheet piles 5 adjacent to the abutment 2 in the width direction is the above-mentioned first end. It is connected to the back surface 2A of the abutment 2 by using the same joint member 9 as described in the embodiment of 4. The steel sheet pile walls 4 arranged on both outer sides of the tracks T1 and T2 may be connected to the side surface 2B of the abutment 2 in the same manner as in the first embodiment described above (example of FIG. 9), or the fourth embodiment. It may be connected to the back surface 2A of the abutment 2 in the same manner as the form (example of FIG. 10).

In the present embodiment, in addition to the steel sheet pile walls 4 on both outer sides of the tracks T1 and T2, the steel sheet pile wall 4D is arranged between the lines of the tracks T1 and T2, and the steel sheet pile wall 4 and the steel sheet pile wall 4D are both bridge stands. It is connected to 2. As a result, the effect of the reinforcing structure 3D on the back surface 2A of the abutment 2 is reduced, and the effect of suppressing the displacement of the abutment 2 in the extension direction (x direction in the figure) of the embankment 1 is enhanced.

11A to 11C are side views of the abutment reinforcement structure according to the sixth embodiment of the present invention. In the reinforcing structure 3E according to the present embodiment, the plurality of steel sheet piles 5 forming the steel sheet pile wall 4 are driven from the first steel sheet pile 5C to the first depth d1 and the first depth d1. Also includes a second steel sheet pile 5D that is driven to a deep second depth d2. In the examples shown in FIGS. 11A to 11C, the depth of the steel sheet pile wall 4 changes stepwise due to the difference in the driving depth of the plurality of steel sheet piles 5. Since the configuration of the present embodiment is the same as that of any of the first to fifth embodiments described above with respect to other points, duplicated description will be omitted.

In the example shown in FIG. 11A, the depth of the steel sheet pile wall 4 is stepwise deeper than the steel sheet pile 5A adjacent to the abutment 2. In the example shown in FIG. 11B, the depth of the steel sheet pile wall 4 is constant from the steel sheet pile 5A to some steel sheet piles 5, and is deepened stepwise from there. For example, when the abutment 2 attempts to roll or tilt around the lower end position 2C on the front surface, a large pulling force is applied to the steel sheet pile 5 away from the abutment 2. By increasing the depth of the steel sheet pile wall 4 as the distance from the abutment 2 increases as described above, the steel sheet pile 5 to which a larger pulling force is applied can obtain a larger vertical bearing capacity.

On the other hand, in the example shown in FIG. 11C, the depth of the steel sheet pile wall 4 is stepwise shallower than the steel sheet pile 5A adjacent to the abutment 2. For example, when the main purpose is to suppress the sliding (horizontal movement) of the abutment 2 in the extension direction (x direction in the figure) of the embankment 1, the steel sheet pile 5 near the abutment 2 is used in the width direction of the steel sheet pile 5. Since the shear resistance force in the x direction in the figure can be obtained, the steel sheet pile 5 away from the abutment 2 is cast shallow enough to exert an auxiliary shear resistance force, and the material of the steel sheet pile 5 is saved. You may.

12A to 12D are side views of the abutment reinforcement structure according to the seventh embodiment of the present invention. In the present embodiment, the reinforcing structure 3F is joined to a position where at least a part of the plurality of steel sheet piles 5 forming the steel sheet pile wall 4 becomes the underground portion after casting, and is orthogonal to the longitudinal direction of the steel sheet pile 5. Further includes a closing member 10 that forms a closing region in the cross section. A method of forming a closed region in a cross section of a steel sheet pile using the closing member 10 is described in, for example, Japanese Patent No. 4916932. By forming the closed region by using the closed member 10, the vertical bearing capacity of the steel sheet pile 5 can be increased. Other than that, the configuration of the present embodiment is the same as that of any of the first to sixth embodiments described above, and therefore duplicate description will be omitted.

In the example shown in FIG. 12A, the closing member 10 is joined to the lower end portion of the steel sheet pile 5 farthest from the abutment 2 among the plurality of steel sheet piles 5. As described above, for example, when the abutment 2 tries to roll or tilt around the lower end position 2C on the front surface, a large pulling force is applied to the steel sheet pile 5 away from the abutment 2. Therefore, if the vertical bearing capacity of the steel sheet pile 5 separated from the abutment 2 is increased by forming the closed region using the closing member 10, the steel sheet pile wall 4 suppresses the rolling or tilting of the abutment 2 as a whole. The effect is enhanced.

In order to obtain the same effect, as in the example shown in FIG. 12B, the present embodiment and the above-mentioned sixth embodiment are combined to deepen the depth of the steel sheet pile wall 4 in a stepped manner and abutment. The closing member 10 may be joined to the lower end portion of the steel sheet pile 5 farthest from 2. Further, as in the example shown in FIG. 12C, the depth of several steel sheet piles 5 including the steel sheet pile 5 farthest from the abutment 2 is set to be deeper than that of the other steel sheet piles 5, and they are used. The closing member 10 may be joined to the lower end of the steel sheet pile 5.

In the example shown in FIG. 12D, the closing member 10 is joined to the steel sheet pile 5 farthest from the abutment 2, the steel sheet pile 5A adjacent to the abutment 2, and the steel sheet pile 5 adjacent to the steel sheet pile 5 among the plurality of steel sheet piles 5. Has been done. Since the steel sheet pile 5 adjacent to the abutment 2 may be subjected to a pushing force when the abutment 2 attempts to roll or tilt around the lower end position 2C on the front surface, the steel sheet pile 5A adjacent to the abutment 2 may be applied. By joining the closing member 10 to the steel sheet pile 5 adjacent to the steel sheet pile 5 and increasing the vertical bearing capacity, the effect of the steel sheet pile wall 4 as a whole to suppress the rolling or tilting of the abutment 2 is enhanced.

FIG. 13 is a diagram showing an example of joining a protruding member to a steel sheet pile in the embodiment of the present invention. As shown in FIG. 13, in the embodiment of the present invention as described above, the projecting member 11 may be joined to at least a part of the steel sheet pile 5 at a position where it becomes an underground portion after casting. The projecting member 11 projects in a direction substantially orthogonal to the width direction (x direction in the drawing) of the steel sheet pile 5 in a cross section orthogonal to the longitudinal direction (z direction in the drawing) of the steel sheet pile 5. By joining such protruding members 11, the shear resistance force in the width direction of the steel sheet pile 5 can be increased. The projecting member 11 is not limited to the plate-shaped member as shown in the illustrated example, and steel materials having various shapes such as H-shaped steel, channel steel, and T-shaped steel can be used for the projecting member 11.

In the above embodiment, an example in which the steel sheet pile 5 constituting the steel sheet pile wall 4 in the reinforcing structure 3 is a hat-shaped steel sheet pile has been described, but various shapes such as a U-shaped steel sheet pile and a straight steel sheet pile have been described. It is possible to construct a steel sheet pile wall with steel sheet piles. Further, in the above embodiment, the steel sheet pile wall 4 supports the soil pressure of the embankment 1 on both sides by driving the steel sheet pile 5 into the embankment 1, but the steel sheet pile 5 is placed in the ground in advance to support the steel sheet pile wall. After constructing 4, the embankment 1 may be formed inside the steel sheet pile wall 4. Alternatively, the steel sheet pile 5 may be placed on the existing embankment 1 to construct the steel sheet pile wall 4, and then the embankment 1 outside the steel sheet pile wall 4 may be removed. In these cases, the steel sheet pile wall 4 constitutes the reinforcing structure 3 of the abutment 2 and also functions as a retaining wall that supports the earth pressure of the embankment 1 on one side.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person having ordinary knowledge in the field of the art to which the present invention belongs can come up with various modifications or modifications within the scope of the technical idea described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

1 ... embankment, 2 ... abutment, 2A ... back, 2B ... side, 2C ... bottom position, 3, 3A, 3B, 3C, 3D, 3E, 3F ... reinforcement structure, 4, 4D ... steel sheet pile wall, 5, 5A ... Steel sheet pile, 5B ... Through hole, 5C ... First steel sheet pile, 5D ... Second steel sheet pile, 6 ... Anchor, 7, 8 ... Connecting member, 9 ... Joint member, 10 ... Closing member, 11 ... Protruding member.

Claims (8)

The back is a reinforcement structure of the abutment adjacent to the end of the embankment in the extension direction.
It consists of a plurality of steel sheet piles connected to each other at the widthwise ends that coincide with the extension direction of the embankment, and has a steel sheet pile wall that supports the earth pressure of the embankment on at least one side.
Of the plurality of steel sheet piles, one end in the width direction of the steel sheet pile adjacent to the abutment is a reinforcing structure of the abutment connected to the abutment. The reinforcing structure for an abutment according to claim 1, further comprising a connecting member for connecting the heads of the plurality of steel sheet piles to each other. The reinforcing structure of the abutment according to claim 1 or 2, wherein one end in the width direction of the steel sheet pile adjacent to the abutment is connected to the side surface or the back surface of the abutment. The abutment according to any one of claims 1 to 3, wherein the steel sheet pile wall is arranged at a position that does not overlap in the horizontal direction with respect to the track or road laid in the extension direction of the embankment. structure. The reinforcing structure for an abutment according to any one of claims 1 to 4, wherein through holes are formed in at least a part of the plurality of steel sheet piles in a direction orthogonal to the width direction. The plurality of steel sheet piles include a first steel sheet pile to be driven to a first depth and a second steel sheet pile to be driven to a second depth deeper than the first depth. The abutment reinforcement structure according to any one of claims 1 to 5. Claim 1 to claim 1, further comprising a closing member which is joined at a position where at least a part of the plurality of steel sheet piles becomes an underground portion after casting and forms a closing region in a cross section orthogonal to the longitudinal direction of the steel sheet piles. Reinforcement structure of the abutment according to any one of 6. A protruding member that is joined at least a part of the plurality of steel sheet piles to be in the ground after being placed and projects in a direction orthogonal to the width direction of the steel sheet piles in a cross section substantially orthogonal to the longitudinal direction of the steel sheet piles. The abutment reinforcing structure according to any one of claims 1 to 7, further comprising.

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