JP2016148196A - Structure and method for reinforcing abutment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reinforcement structure capable of reducing earth pressure applied to an abutment during earthquakes and capable of obtaining excellent earthquake resistance, and a reinforcement method for the same.SOLUTION: In a structure for reinforcing an abutment, a fill improvement body 10 made of a plurality of columnar bodies is vertically provided in fill S that is positioned on the side of a back surface 1a of the abutment 1. The plurality of fill improvement bodies 10 are arranged like a wavy line formed of a linear line, in the state of being connected like a wall in such a manner as to adjoin each other in a direction crossing a bridge axis direction X along an extension direction of a bridge B in a plan view.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a road or railroad abutment having a back portion formed on embankment, and more particularly to a reinforcing structure and a reinforcing method for improving the earthquake resistance of the abutment.

  In the case of road abutments and railway abutments where the back part is formed of embankment, the earth pressure of the embankment located on the back side of the abutment, that is, the earth pressure of the back embankment increases and damages the frame when an earthquake occurs There is a risk of causing subsidence or collapse of the embankment or a girder falling bridge. For this reason, various reinforcing techniques for suppressing such damage have been proposed. For example, in the reinforcement technique according to Patent Document 1, a reinforcement block is provided on the side surface of the abutment and a ground reinforcement material is embedded in the backfill.

JP 2011-247059 A

  As described above, for reinforcement for enhancing the earthquake resistance of the abutment, a technique such as that shown in Patent Document 1 has been proposed, but for the technique for improving the traveling safety of a vehicle such as a train, There is no upper limit, and for this reason, there is a need for an abutment equipped with a reinforcing structure that further enhances earthquake resistance.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide an abutment reinforcing structure excellent in earthquake resistance and a reinforcing method thereof.

  In order to achieve the above object, the abutment reinforcement structure according to the present invention is a reinforcement structure of an abutment in which a banking improvement body composed of a plurality of columnar bodies is provided in a vertical direction in the banking located on the back side of the abutment, The plurality of embankment improvement bodies are arranged in a state of being connected in a wall shape so as to be adjacent to each other in a direction intersecting the bridge axis direction along the extending direction of the bridge in a plan view.

  The abutment reinforcing method according to the present invention is a method for reinforcing an abutment in which a banking improvement body composed of a plurality of columnar bodies is provided in a vertical direction in the banking located on the back side of the abutment. The plurality of embankment improvement bodies are constructed in a state of being adjacent to each other in a direction intersecting the bridge axis direction along the extending direction, and the plurality of embankment improvement bodies are arranged in a state of being connected in a wall shape. It is characterized by.

In the present invention, in the embankment located on the back side of the abutment, a plurality of embankment improvement bodies connected so that the arrangement direction intersects with the direction of the bridge axis is provided in the shape of a wall. The earth pressure wave is cut by the wall-like embankment improvement body and becomes smaller. Thereby, the earth pressure added to the back of an abutment can be disperse | distributed.
Furthermore, the vibration of the embankment that is swung by the earthquake is attenuated and reduced by the friction between the embankment and the plurality of embankment improvement bodies. Therefore, the earth pressure of the embankment applied to the back of the abutment when an earthquake occurs can be reduced, and the seismic performance of the abutment can be improved.

Further, by integrating the embankment improved body and the abutment, or by integrating the embankment on which the embankment improved body is constructed and the abutment, it is possible to provide the abutment with excellent earthquake resistance.
Furthermore, since the several embankment improvement bodies are provided so that it may mutually adjoin, it can suppress that the embankment loosened by the vibration at the time of an earthquake flows out outside. For this reason, it is possible to prevent damage to the abutment frame, and to prevent settlement and collapse of the embankment when an earthquake occurs.

  In the reinforcing structure of the abutment according to the present invention, it is preferable that the plurality of embankment improvement bodies are arranged in a wavy line formed in a straight line while extending along the bridge axis direction in a plan view. .

  Further, in the abutment reinforcing structure according to the present invention, it is preferable that the plurality of embankment improvement bodies are arranged in a shape in which X-shapes are continuous while extending along the bridge axis direction in a plan view. .

  In the present invention, a plurality of embankment improvement bodies can be arranged in a plurality of locations along the bridge axis direction where the wall-like bodies connected in a straight line intersect with the bridge axis direction in plan view. The earth pressure wave at the time of an earthquake can be effectively divided.

  Further, the reinforcing structure of the abutment according to the present invention is such that the abutment is for a railroad provided with a track, and the improved body group in which the plurality of embankment improvement bodies are arranged is provided on both sides of the track. It is preferable.

  In the present invention, the track is held from both sides by the improved body group formed by the plurality of embankment improved bodies, and the improved body group and the abutment are integrally provided via the track, so that the earthquake resistance of the abutment is further improved. be able to.

  According to the reinforcing structure and the reinforcing method of the abutment of the present invention, the earth pressure received by the abutment at the time of an earthquake can be reduced, and an excellent seismic resistance can be obtained.

It is a top view which shows the structure of the reinforcement structure of the abutment by embodiment of this invention. It is the X1-X1 sectional view taken on the line shown in FIG. 1, Comprising: It is the front view which looked at the abutment from the bridge girder side. It is the X2-X2 sectional view taken on the line shown in FIG. 1, Comprising: It is the front view which looked at the abutment from the bridge girder side. It is a top view which shows the structure of the reinforcement structure of the abutment by other embodiment of this invention.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of an abutment reinforcing structure and a reinforcing method according to the present invention will be described with reference to the drawings.

1 to 3 show an example in which the abutment reinforcing structure according to the present embodiment is applied to a railway bridge B. FIG.
This bridge B has an abutment 1 at a location located at the boundary between the bridge girder G and the embankment S. On the bridge girder G and embankment S, two tracks T1 and T2 including a pair of rails R are laid through a ballast S1 and sleepers W. That is, on this bridge girder G and embankment S, a track for double tracks is laid. The embankment S is located on the back surface 1a side of the abutment 1 when the abutment 1 is viewed from the bridge girder G side.
Here, the direction orthogonal to the back surface 1a of the abutment 1 (the extending direction of the bridge B), that is, the extending direction of the tracks T1 and T2 is referred to as a bridge axis direction X.

  The abutment 1 is constructed of reinforced concrete, and is provided integrally with the pile on a pile (not shown) placed on the ground. That is, the abutment 1 is located between the bridge girder G and the embankment S, supports the bridge girder G from below, and resists the earth pressure from the back surface 1 a of the abutment 1 by the wall body and the foundation of the abutment 1. Formed on a pile earth pressure abutment.

  The embankment improvement body 10 is composed of a plurality of columnar bodies in the embankment S located on the back side of the abutment 1. The plurality of embankment improvement bodies 10 are connected in a wall shape so as to be adjacent to each other in a direction intersecting the bridge axis direction X in a plan view (that is, a direction intersecting at an angle other than a right angle to the bridge axis direction X). Arranged in a state. More specifically, the plurality of embankment improvement bodies 10 extend in the bridge axis direction X in a plan view and are arranged in a wavy line formed in a straight line. And the improvement body group 10A in which the several embankment improvement bodies 10 are arranged is each provided in the position of the both sides which pinched | interposed the double track | orbits T1 and T2, and both track | orbits T1 and T2.

The embankment improvement body 10 is constructed at a depth from the surface of the embankment S to the vicinity of the lower end of the abutment 1, and is provided so that the axial direction of the embankment improvement body 10 described later is a vertical direction.
The embankment improvement body 10 forms a straight line portion in which four embankment improvement bodies 10 are connected to form a wavy line. The wall surface formed from the straight portion is arranged so as to intersect with the bridge axis direction X at an angle of 45 degrees in plan view.

  The embankment improvement body 10 is an improvement body made of soil cement, and is constructed with a diameter of several hundred mm, for example. The construction range of the embankment improvement body 10 is a range extending from the position of the back surface 1a of the abutment 1 by a predetermined distance in a direction away from the abutment 1 in the bridge axis direction X. The diameter dimension, the number of installations, and the construction range of these embankment improvements 10 are appropriately determined depending on the properties of the embankment S and the like.

Next, the construction method of the embankment improvement body 10 mentioned above is demonstrated based on drawing.
This construction is performed using a time zone in which the train is not traveling on the tracks T1 and T2, for example, a time zone from the last train to the first train.

First, as shown in FIGS. 1 to 3, a ground improvement machine (not shown) having a hole drilling drill is transported to a construction site and set at a predetermined improvement position. The ground improvement machine can also be transported by using the tracks T1 and T2.
Next, the embankment improvement body 10 made of a columnar body is formed by excavating the embankment S with a drilling agitating drill toward the lower side in the vertical direction and simultaneously injecting cement milk to stir and solidify the excavated soil and cement milk. The

  And after the several embankment improvement body 10 is constructed every other along these arrangement directions, it constructs between the adjacent embankment improvement bodies 10 mutually. Thereby, the wall-shaped improvement body group 10A arranged in a wavy line is constructed on both sides and the middle of the tracks T1 and T2.

The reinforcement structure of the abutment 1 constructed in this way is a plurality of embankments that are connected in the embankment S located on the back surface 1a side of the abutment 1 so that the arrangement direction intersects the direction of the bridge axis X. Since the improved body 10 is provided in a wall shape, the earth pressure wave in the direction along the bridge axis direction X at the time of the earthquake is divided by the wall-shaped embankment improved body 10 and becomes smaller. Thereby, the earth pressure added to the back surface 1a of the abutment 1 can be disperse | distributed.
Furthermore, the vibration of the embankment S that is swung by an earthquake is attenuated and reduced by the friction between the embankment S and the plurality of embankment improvement bodies 10. Therefore, the earth pressure of the embankment S applied to the back surface 1a of the abutment 1 when an earthquake occurs can be reduced, and the seismic performance of the abutment 1 can be improved.

Further, by integrating the embankment improvement body 10 and the abutment 1 or by integrating the embankment S on which the embankment improvement body 10 is constructed and the abutment 1, the abutment 1 is further provided with excellent earthquake resistance performance. Can do.
Furthermore, since the several embankment improvement bodies 10 are provided so that it may mutually adjoin, it can suppress that the embankment S loosened by the vibration at the time of an earthquake flows out outside. For this reason, damage to the frame of the abutment 1 can be prevented, and the settlement and collapse of the embankment S when an earthquake occurs can be prevented.

  Further, in the present embodiment, a plurality of portions along the bridge axis direction X in which a plurality of embankment improvement bodies 10 are arranged and linearly connected wall-like bodies intersect the bridge axis direction X in plan view. Since it can be provided at a location, the earth pressure wave during an earthquake can be effectively divided.

  Further, in the present embodiment, double-track tracks T1 and T2 are held from both sides by an improved body group 10A formed by a plurality of embankment improvement bodies 10, and the improved body group 10A and the abutment 1 pass the tracks T1 and T2. Therefore, the earthquake resistance of the abutment 1 can be further improved.

As mentioned above, although embodiment of the reinforcement structure and reinforcement method of the abutment by this invention was described, this invention is not limited to said embodiment, It can change suitably in the range which does not deviate from the meaning.
For example, in the above-described example, the bridge B is used for the railway on which the tracks T1 and T2 are laid. However, the bridge B may be a road bridge on which a vehicle such as an automobile travels.
Further, the present invention is not limited to the double-track trajectories T1 and T2 as in the present embodiment, and may be a single-track trajectory.

  In addition, the planar shape arranged by the plurality of embankment improvement bodies 10 is a wavy line formed in a straight line in the present embodiment, but is not limited to such a shape, and the bridge Other shapes may be used as long as a plurality of embankment improvement bodies are arranged in a direction intersecting the axial direction X.

For example, as shown in FIG. 4, the embankment improvement body 10 extends in the bridge axis direction X in a plan view and is arranged in a shape in which X shapes are continuous.
The plurality of embankment improvement bodies 10 arranged in this way are also provided by the same construction method as the embankment improvement body 10 arranged in a wavy line. And also in the case of the embankment improvement body 10 arrange | positioned in this X shape, since the arrangement direction is suitable for the direction which cross | intersects with respect to the bridge axis direction X, the embankment improvement body 10 arrange | positioned in the above-mentioned wavy line shape and Similar effects can be obtained.

  Further, in the present embodiment, the positions where the improved body group 10A is arranged are provided on both sides of the double-tracked tracks T1 and T2 and between the tracks T1 and T2, respectively. There is no limit. For example, it is also possible to omit the improved body group 10A arranged between the two tracks T1 and T2.

  Moreover, as a position of the some embankment improvement body 10, in the embodiment mentioned above, it arranges from the position adjacent to the back surface 1a of the abutment 1. That is, the end of the improved body group 10A on the abutment 1 side is in contact with the back surface 1a, but is not limited to this position, and a plurality of embankment improved bodies 10 are arranged from a position separated from the back surface 1a. Also good.

  Moreover, in this Embodiment, it is set as the method of constructing between the adjacent embankment improvement bodies 10 after constructing every other in order of the arrangement direction as a construction procedure of the embankment improvement body 10, It is not limited to being a procedure. In other words, the embankment improvement body 10 may be constructed in the order in which they are arranged, or may be constructed from a place where construction is easy according to on-site conditions.

  In addition, it is possible to appropriately replace the components in the above-described embodiments with known components without departing from the spirit of the present invention.

B Bridge S Embankment S1 Ballast R Rail W Sleeper G Bridge girder T1, T2 Track 1 Abutment 1a Back 10 Embankment improvement body 10A Improvement body group

Claims (5)

A reinforcement structure of an abutment in which an embankment improvement body composed of a plurality of columnar bodies is provided in a vertical direction in the embankment located on the back side of the abutment,
The plurality of embankment improvement bodies are arranged in a state of being connected in a wall shape so as to be adjacent to each other in a direction intersecting the bridge axis direction along the extending direction of the bridge in a plan view. Reinforced structure.   2. The abutment reinforcement structure according to claim 1, wherein the plurality of embankment improvement bodies extend in the bridge axis direction in a plan view and are arranged in a wavy line formed in a straight line. .   2. The abutment reinforcement structure according to claim 1, wherein the plurality of embankment improvement bodies extend in the bridge axis direction in a plan view and are arranged in a shape in which X shapes are continuous. . The abutment is for railways with tracks,
The abutment reinforcement structure according to any one of claims 1 to 3, wherein the improvement body groups in which the plurality of embankment improvement bodies are arranged are respectively provided on both sides of the track. A method for reinforcing an abutment in which an embankment improvement body composed of a plurality of columnar bodies is provided in a vertical direction in the embankment located on the back side of the abutment,
Construction of the plurality of embankment improvements in a state adjacent to the direction crossing the bridge axis direction along the extending direction of the bridge in plan view,
The abutment reinforcing method, wherein the plurality of embankment improvement bodies are arranged in a state of being connected in a wall shape.

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