JP2895401B2 - Construction method of reinforced earth body and its structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an embankment having a backside of an abutment, an embankment for directly supporting a building, an embankment subjected to a traffic load such as a train, and a ballast ballast, and an embankment or ballast reinforced earth whose settlement after construction is severely restricted. The present invention relates to a method for constructing a body and its structure.

[0002]

2. Description of the Related Art Generally, embankment has remarkably low compressive rigidity as compared with iron or concrete, and large compressive settlement occurs due to its own weight, traffic load, and load. Therefore, in general embankment construction, each operation of dispersing, leveling, and compacting is repeated, and the construction is performed by stacking. However, with this method, it is difficult to directly support structures such as buildings and piers with the embankment because the amount of compression settlement after embankment construction is large.

In order to cope with such a case, there are three methods: (1) a method of not transmitting a load to the embankment, (2) a method of improving the embankment, and (3) a method of promoting the settlement of the embankment in advance. Will be dealt with in a way.

[0004]

However, the above-mentioned method for dealing with the embankment has the following problems. (1) As a method of not transmitting a load to the embankment, there is a method of driving a pile to a high-quality ground below the embankment, but the cost associated with driving the pile increases. (2) As a method of improving the embankment, there is a method of adding cement or lime to the embankment and chemically solidifying it. In this case, in addition to an increase in cost, construction management and quality control are complicated. Become. There is also a method of arranging a tensile reinforcing material such as geotextile in accordance with the embankment construction, but the settlement amount has not been significantly improved.

(3) As a method for promoting the settlement of the embankment in advance, a preloading method is generally used. This method
After constructing a specific embankment, extra soil of a weight equivalent to the structure or train load is laid up and removed after the subsidence is completed, but a lot of labor and construction time are required. Was. In addition, the release of the preload does not maintain good sinking properties when the preload is applied. Furthermore, since an extra load acts not only on the embankment but also on the ground, the ground may collapse on soft ground.

On the other hand, the embankment does not have a very high compression rigidity. Therefore, when a traffic load such as a train acts dynamically,
In some cases, it may cause problems in ride comfort and running stability. In particular, in the case of a slab track, since a train load acts directly on the embankment without a ballast, the restrictions on settlement and compression rigidity become even more severe. Therefore, in such a case, rigid and wide subgrade concrete is installed between the slab track and the embankment to reduce the stress acting on the embankment, but the construction of this subbase increases the cost. Has been invited.

In the case of a general ballast track, the train load is directly supported by a ballast via a sleeper. However, due to insufficient compaction, settlement occurs in the initial stage of the track construction, and Even later, residual deformation is accumulated over time due to the lateral flow of the ballast. Therefore, at present, the track is maintained in a constant state by replenishing the ballast sinking. In this case,
This has led to an increase in maintenance costs.

The present invention eliminates the above-mentioned problems, and can easily improve the compression stiffness and settlement characteristics of the embankment without using the ground improvement, pile driving, and the conventional preloading method. An object of the present invention is to provide a method of constructing a reinforcing earth body without applying an extra load and a structure thereof.

[0009]

The present invention SUMMARY OF], in order to achieve the above object, (1) In the method for constructing a reinforced soil body, ground to place the lower horizontal loading plate, given to the lower horizontal loading board The embankment is piled up to the height of the embankment, an upper horizontal loading plate is arranged on the upper surface of the embankment to be piled up, and the lower horizontal loading plate and the upper horizontal loading plate are connected by a vertical tendon and a preload is applied to the embankment, The vertical tension member is fixed to the upper horizontal loading plate with the preload slightly released.

(2) How to construct the reinforced earth body according to (1) above
In the method, the embankment to be piled is cohesive soil. (3) In the method for constructing a reinforced soil body according to the above (1) or (2), when the compressive strength of the piled-up embankment is insufficient, a tensile reinforcing material is provided in a horizontal direction in accordance with the rolling pressure of the embankment. They are arranged.

( 4 ) In the reinforced earth structure, a lower horizontal loading plate disposed on the ground, a vertical tension member having one end fixed to the lower horizontal loading plate, and an embankment stacked on the lower horizontal loading plate And an upper horizontal loading plate disposed on the upper surface of the embankment to be stacked, and connecting the lower horizontal loading plate and the upper horizontal loading plate with the vertical tension member to apply a preload to the embankment, and then performing the preloading. Means for fixing the vertical tension member to the upper horizontal loading plate in a slightly released state.

( 5 ) In the reinforced earth structure, a lower horizontal loading plate disposed on the ground, a vertical tension member having one end fixed to the lower horizontal loading plate, and embankment rolling on the lower horizontal loading plate. An embankment having a tensile reinforcement arranged horizontally in accordance with the pressure, an upper horizontal loading plate arranged on the upper surface of the piled up embankment, and the lower horizontal loading plate and the upper horizontal loading plate are formed by the vertical tendon. Means for fixing the vertical tension member to the upper horizontal loading plate in a state where the preload is slightly released after the preload acts on the embankment.

( 6) The reinforced soil according to (4) or (5) above
In the body structure, viscous
It uses earth. (7) In the reinforced earth structure according to (4), (5) or (6), the lower horizontal loading plate may be used for a reinforced concrete abutment having a bottom reinforced concrete plate and the upper horizontal loading plate may be a small abutment. It was made.

(8) In the reinforced earth structure according to (4), (5) or (6), the lower horizontal loading plate is a bottom reinforced concrete plate, and the upper horizontal loading plate is a top bottom reinforced concrete plate and the vertical. It is intended to be used for a building foundation where the tendon is a PC steel bar. (9) In the reinforced earth structure according to (4), (5) or (6), the lower horizontal loading plate is a roadbed concrete or a pressure receiving plate, and the upper horizontal loading plate is a concrete sleeper and the vertical tension member. It is intended to be used for the railroad track base of ballast ballast, which is a reinforcing bar.

(10) In the reinforced earth structure according to (4), (5) or (6), the lower horizontal loading plate is a reinforced concrete bottom plate, and the upper horizontal loading plate is a slab plate and the vertical tension member. Is used for the base of the slab railroad track, which is a reinforcing bar.

[0016]

According to the present invention, as described above, a preloaded material is applied to the embankment to obtain a reinforced earth structure which maintains the state. Alternatively, a preload is applied to the embankment, and thereafter, the preload is partially released by a predetermined amount, and the state is maintained. For this purpose, the present invention installs horizontal loading plates on the upper and lower surfaces of the embankment, and installs a vertical tendon for tightening the embankment between the upper and lower loading plates. In addition, a horizontal tension reinforcing member is arranged as necessary in the embankment between the upper and lower horizontal loading plates so that the embankment does not compress and break due to the tension. Thereafter, the tension is partially released by a predetermined amount after the preloading of the vertical tendon is applied.

[0017] By these constructions, it is possible to construct a high-quality embankment having extremely high deformation performance and very little compression settlement. That is, (1) soil rigidity improving effect by preload, (2) compressive reinforcing effect of vertical tendon, (3) soil tensile reinforcing effect by horizontal tensile reinforcing material, (4) soil by partial stress release of preload. The compression rigidity and settlement characteristics of the embankment are remarkably improved by the four functions of improving the rigidity of the embankment.

Further, unlike the conventional preloading method, no extra load is applied to the ground.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a reinforced earth structure showing an embodiment of the present invention. As shown in this figure, an embankment 2 is stacked on a ground 1 that supports the embankment. A lower horizontal loading plate 3 is arranged at the bottom of the embankment 2, and an upper horizontal loading plate 4 is arranged on the upper surface of the embankment 2 so as to face the lower horizontal loading plate 3. Further, the tip of a vertical tension member 5 is fixed to the lower horizontal loading plate 3, and the other end of the vertical tension member 5 penetrates the upper horizontal loading plate 4, and a fixing jig 6 is attached to the upper surface of the upper horizontal loading plate 4. It is constituted so that it can be fixed.
Here, when the compressive strength of the embankment is insufficient, the horizontal tension reinforcing members 7 are arranged in the horizontal direction in accordance with the rolling pressure of the embankment.

Next, a method of constructing a reinforced earth body according to the present invention will be sequentially described. The reinforced earth body of the present invention is characterized in that a preload is applied to the embankment 2, and then the preload is partially released by a predetermined amount and the state is maintained. For this reason, the present invention provides the lower horizontal loading plate 3 on the upper surface of the ground 1.
Then, the upper horizontal loading plate 4 facing this is installed, and the vertical tension member 5 for tightening the embankment between the lower horizontal loading plate 3 and the upper horizontal loading plate 4 is installed. In addition, a horizontal tension reinforcing member 7 is arranged in the embankment 2 between the lower horizontal loading plate 3 and the upper horizontal loading plate 4 as necessary so that the embankment 2 is not compressed and broken due to the tension. Thereafter, after applying a preload in which the vertical tendon 5 is tensioned, the tension is partially released by a predetermined amount. By these operations, it is possible to construct a high-quality embankment having extremely high deformation performance and very little compression settlement, and a reinforced earth structure can be obtained.

Hereinafter, the method of constructing the reinforced earth body of the present invention and its operation will be described. (1) Soil rigidity improving effect by preloading FIG. 2 is an explanatory diagram of a stress state of soil. In this figure,
P is the load, A is the area of the load plate, _SN is the amount of soil deformation due to the P load, σ _v is the vertical stress acting on the soil element, σ
_h is the horizontal stress applied to the soil element, L is the vertical distance between the lower horizontal loading plate 3 and the upper horizontal loading plate 4, deformation coefficient E _N of the soil, [(P / A) · L / S _N ].

Therefore, the stress state of the underground element is such that, in the initial state without a preload, a vertical stress of σ _vo and a horizontal stress of σ _ho act, and Δσ _v , Δσ _h due to the subsequent load.
Is increased. Subsidence for mounting load P in this case is dependent on the modulus of deformation of the soil _{E (= Δσ v / Δε v} ), deformation coefficient E of the soil increases as vertical stress .DELTA..sigma _v increases.

FIG. 3 shows the relationship between stress and strain in soil when loading is performed without performing preloading. FIG.
FIG. 3A is a diagram illustrating a relationship between stresses in the soil, and FIG. 3B is a diagram illustrating a relationship between strains in the soil. In FIG. 3A, the horizontal axis represents the horizontal stress σ _h acting on the soil element, the vertical axis represents the vertical stress σ _v acting on the soil element, a represents the stress state of the soil when no load is applied, and b represents the P load. Is the stress state of the soil at the time of loading, A is σ
_v and σ _h are a 1: 1 straight line, and B is a fracture envelope. In FIG. 3 (b), the horizontal axis represents the vertical strain increment Δε _v of the submerged element accompanying the loading, and the vertical axis represents the loading. The accompanying vertical stress increments Δσ _v of the soil elements are shown.

[0024] Therefore, deformation coefficient E of the soil are generally sigma _v function ^{_{(E = α · σ v m}} ), σ v increases,
The soil deformation coefficient E also increases. In FIG. 3, the deformation coefficient of soil when loaded from the state without preload is E _N
It is. On the other hand, FIG. 4 shows an explanatory diagram of the stress-strain relationship in the soil when the preload Tp is applied.
FIG. 4A is an explanatory diagram of a stress relationship in soil when a preload Tp is applied, and FIG. 4B is an explanatory diagram of a strain relationship in the soil when a preload Tp is applied.

In FIG. 4A, the horizontal axis represents the horizontal stress σ _h acting on the soil element, and the vertical axis represents the vertical stress σ _v acting on the soil element. Stress state, c
Is the stress state of the soil when the preload Tp is applied, d is the stress state of the soil when the P load is applied from c, and A is σ _v and σ _h
Is a 1: 1 straight line, and B is a destructive envelope. In FIG. 4B, the horizontal axis represents the vertical strain increment Δε of the submerged element due to loading.
_v, the vertical axis represents the vertical stress increment .DELTA..sigma _v of soil element with the loading, respectively, E _T is the modulus of deformation of the soil when adding preload, E _P further deformation of the soil when a load is applied The coefficient is shown.

[0026] As is apparent from these figures, deformation coefficient E _p of the soil from the state in which the action of preloaded, improved as compared with deformation stiffness E _T of soil from a state which does not act preloaded (Tp = 0) Will be done. This effect is the effect of (1) improving the rigidity of the soil by the preload. (2) Compressive reinforcing action of vertical tendons On the other hand, the vertical tendons after preloading have a tensile force T
p is acting. When the load P is applied in this state, the reaction force Rp (= Ep · A · Δε _v ) due to the soil is to be resisted. Division.

FIG. 5 is a schematic view of the resistance mechanism between the soil and the vertical tendon. Here, K is the spring coefficient of the vertical tendon, E
p · A spring coefficient of the soil from the state in which the action of preloaded, [Delta] [epsilon] _v is the distortion increment generated by placing a load.
Here, in the structure to which the preload is applied, the load P is supported by the compression spring reaction force 8 (= Ep · A · Δε _v ) of the soil and the compression spring reaction force 9 (= K · Δε _v ) of the vertical tension member. will be, vertical spring coefficient K of the tendons load is shared soil as increases and decreases, subsidence (Δε _v · L) is reduced. Here, the vertical tension member is originally intended to resist the tensile force Tp due to the preload, and generally has a large slenderness ratio. Therefore, when a large compressive load is applied, buckling occurs. However, in this structure, when the compressive force acting on the vertical tendon is equal to or less than the preload Tp, the compressive force does not act on the vertical tendon as a whole, so that it does not buckle. This action is the compression-strengthening action of the vertical tendon member (2). (3) Tensile Reinforcement Action by Horizontal Tensile Reinforcement In the reinforced earth structure of the present invention, the preload is added to the embankment to reinforce and improve the soil. However, the soil improvement effect is higher as the preload is larger. It is clear from FIG. However, since the prerequisite of this structure is that the soil does not compressively break at the preload Tp, the present invention arranges a tensile reinforcing material such as geotextile horizontally in the soil as necessary to compress the soil. They decide to reinforce the soil against destruction.

Here, the horizontal tension reinforcing member 7 arranged in the horizontal direction restrains the lateral flow of the embankment material due to compaction, and assists in efficient compaction. In addition, even with respect to the compressive fracture of the soil, a greater preload can be applied since the soil is reinforced by the tensile resistance of the horizontal tensile reinforcement. In addition, since the horizontal tensile reinforcement itself contributes to the improvement of the rigidity of the soil, the amount of settlement caused by loading can be further reduced. This effect is the tensile reinforcing effect of the horizontal tensile reinforcing member of (3). (4) Soil stiffness improving action by partial preload release In the present invention, a part of the preload load is released,
It decides to fix the vertical tendon. This focuses on the point that reloading after adding a load history can obtain a reinforced earth structure with higher quality than soil rigidity when no history is given. It was done.

FIG. 6 is a diagram showing the relationship between stress and strain in the soil when a part of the preload is released and reloading is performed. FIG.
(A) is an explanatory diagram of the stress relationship in the soil when a part of the preload is released after the preload Tp is actuated and reloaded, and FIG. 6 (b) is the strain relationship in the soil in that case. FIG. In FIG. 6A, the horizontal axis represents the horizontal stress σ _h acting on the soil element, the vertical axis represents the vertical stress σ _v acting on the soil element, A represents a straight line in which σ _v and σ _h are 1: 1, and B Is the fracture envelope, a is the soil stress state when no load is applied, e is the soil stress state when the preload is applied, f is the soil stress state when the preload is partially released, and g is f to P In FIG. 6 (b), the horizontal axis indicates the vertical strain increment Δε _v of the soil element due to loading, and the vertical axis indicates the vertical stress increment Δσ of the soil element according to loading. _v indicates respectively, E _r is the modulus of deformation of the soil at the time of re-loading, the E _P is a variation coefficient of the soil when no re-loading.

[0030] As is apparent from these figures, deformation coefficient E _r at the time of re-loading is improved compared with the deformation coefficients before re-loading E _P. However, in this case, the preload effect of the above (1) is reduced by an amount corresponding to the release of the preload, so that the condition of the above (2) is more excellent than the effect of the above (1), or the stress relaxation. For example, it is desirable to perform the process on soil under conditions where it is difficult to secure the effect (1).

Therefore, it is considered that the method is effective particularly in the cohesive soil. This action is the action (4) for improving the rigidity of the soil by partial preload release. Hereinafter, application examples of the reinforced earth structure obtained by the method for constructing a reinforced earth body of the present invention will be described. FIG. 7 is an example in which the method for constructing a reinforcing earth body of the present invention is applied to an abutment portion.

As a specific construction procedure, first, the ground 1
A bottom reinforced concrete plate 15 as a lower loading plate is placed on the bottom surface of the embankment 14 on the bottom. The vertical tendon 17 is connected to the bottom reinforced concrete plate 15 and the embankment 14 is constructed one layer at a time. At this time, a horizontal tensile reinforcing material 13 such as geotextile is installed in accordance with the rolling pressure of the embankment, and is wrapped around the sandbag 12 as a temporary restraint on the wall surface. An embankment is constructed to a predetermined embankment height, and a small abutment 16 as an upper loading plate is constructed thereon. The bridge abutment 16 is previously punched with a PVC pipe 18 or the like so that the vertical tendon 17 can be penetrated.

After the abutment 16 is constructed, a tensile force is applied to the vertical tension member 17 with a nut or jack to apply a preload to the embankment 14. The magnitude of the preload is such that the embankment 14 is not compressed and fractured.
About twice as large as If the preload comes off, you will be nervous. After the preload is in a steady state, part of the preload load is released. The release amount at that time is set to about the applied load P, although it depends on the type of soil. After release, the vertical tension member 17 and the bridge stand 16 are fixed, and then the girder 19 is installed.

Finally, the wall concrete 11 on the front of the sandbag 12 is cast. The construction method of the embankment shown here is an example of construction based on the “stabilization method of reinforcing embankment and its structure” which has already been proposed by the present inventor as Japanese Patent Publication No. 4-53204. With such a configuration, it is possible to construct an abutment having extremely high deformation performance and very little compression settlement by a simple construction method.

FIG. 8 shows an example in which the method for constructing a reinforced earth body of the present invention is applied to a building foundation. In this case,
Before embankment of the embankment 22 upward, a bottom reinforced concrete plate 21 as a lower horizontal loading plate is cast on the bottom surface. Connection of PC steel bar 23 which is a vertical tendon, geotextile 2
The installation method of the horizontal tension reinforcing member such as 4 and the embankment 22 are the same as those in the embodiment in FIG. On the upper surface of the embankment 22, an upper reinforced concrete plate 2 as an upper loading plate
5 is installed, the PC steel bar 23 is attached, and a preload is applied to the PC steel bar 23 under the same management as in the embodiment (1). A structure such as a building 26 is installed on the upper reinforced concrete plate 25.

With this configuration, it is possible to greatly reduce the compression settlement of the embankment due to the building load by a simple construction method. 9 and 10 show an example in which the method for constructing a reinforced earth body of the present invention is applied to a railway track. FIG. 9 shows an example in which the method for constructing a reinforced soil body of the present invention is applied to a railway track base having a ballast.

A subgrade concrete 31 as a lower horizontal loading plate is already placed on the upper surface of the reinforced embankment or the ground 30 which has been constructed (or a pressure receiving plate such as a concrete plate or an iron plate may be provided). A threaded mounting bracket 32 is embedded in the roadbed concrete 31, and a reinforcing bar 33 as a vertical tension member is connected. The ballast ballast 34 is sprayed, and a concrete sleeper 35 as an upper horizontal loading plate is installed.
The concrete sleeper 35 penetrates the reinforcing bar 33 as a vertical tension member every few wires, applies a tensile force to the reinforcing bar 33 with a nut 37, a jack or the like, and applies a preload to the ballast 34.

Thereafter, the rail 36 is attached to the concrete sleeper 35 by a predetermined method. At this time, the arrangement interval of the reinforcing bars 33 as the vertical tendon is determined by the degree of rigidity of the rail. The higher the rigidity, the wider the arrangement interval becomes, and the load for tightening the vertical tendon increases. Here the ballast ballast 34
Has sufficient strength against compressive failure, and in this case, there is no need to particularly install a horizontal tensile reinforcement. Instead, roadbed concrete upper surface 3 as pressure plate upper surface
In order to restrain the ballast 34 on the lower surface of the concrete sleeper 1A or the concrete sleeper 35A, it is possible to tighten the ballast 34 more effectively if it has irregularities of about the same size as the ballast.

Thereafter, a preload equivalent to the train load is applied to the vertical tendon under the same management as in the embodiment of FIG. As a result, the ballast ballast can be efficiently compacted, the concrete sleepers and the ballast ballast can be adapted, and at the same time, the rigidity of the ballast ballast can be improved. With such a configuration, it is possible to reduce the initial deformation and residual change amount of the ballast caused by running the train by a simple construction method, and to reduce the load and cost required for maintenance.

FIG. 10 shows an example in which the method for constructing a reinforced earth body according to the present invention is applied to a slab railroad track foundation. A bottom reinforced concrete plate 41 as a lower horizontal loading plate is already placed on the upper surface of the constructed reinforcing embankment or the ground 40 (or a pressure receiving plate such as an iron plate may be provided). A screw-shaped mounting bracket 43 is embedded in the bottom reinforced concrete plate 41, and a reinforcing bar 44 as a vertical tension member is connected. Therefore, the embankment 42 is raised, and the slab plate 4 serving as the upper horizontal loading plate is raised.
5 is installed. The slab plate 45 penetrates the reinforcing bar 44 as a vertical tension member every few lines, applies a tensile force to the reinforcing bar 44 with a nut 46, a jack or the like, and applies a preload to the embankment 42.
Thereafter, the rail 47 is attached to the slab plate 45 by a predetermined method. At this time, the arrangement interval of the reinforcing bar 44 as the vertical tension member is determined by the degree of the rigidity of the rail.
The arrangement interval is widened, and the load for tightening the vertical tendon increases.

[0041] With this configuration, the roadbed concrete, asphalt pavement, grain crushed stone, and the like disposed below the slab plate used in the conventional slab railway track are omitted, and the reinforced earth body of the present invention is omitted. A simple structure of only a slab plate can be provided on a structure. As described above, the simple configuration of the lower horizontal loading plate, vertical tendon, upper horizontal reinforcement, etc. can significantly improve the deformation performance of soil and rubble materials, and embankments and railways where settlement is severely restricted. It can be widely applied to orbits and the like.

Further, unlike the conventional preloading method, no extra load is applied to the ground. It should be noted that the present invention is not limited to the above embodiments, and various modifications are possible based on the gist of the present invention, and they are not excluded from the scope of the present invention.

[0043]

As described above, the present invention has the following effects. ( 1 ) According to the first aspect of the present invention, by adding a load history once and reloading, it is possible to obtain a reinforced earth structure having a higher quality than the rigidity of the soil when no history is given. it can.

[0044] (2) According to the second aspect of the present invention, loading
The embankment to be raised is partially
Preload release can improve soil stiffness
You. (3) According to the third aspect of the invention, in addition to the effect of the above (1) or (2), it is possible to obtain a high-quality reinforced earth structure having a tensile reinforcing action by a horizontal tensile reinforcing material. .

( 4 ) According to the invention as set forth in claim 4, by adding a load history once and reloading, a reinforced earth structure having a higher quality than the rigidity of the soil when no history is given is obtained. Can be provided. ( 5 ) According to the invention of claim 5, in addition to the effect of the above ( 4 ), even when the compressive strength of the embankment to be piled is insufficient, high-quality reinforcement without compressive failure of the embankment due to tension. An earth structure can be provided.

[0046] (6) According to the sixth aspect of the present invention, loading
Because the embankment to be raised is clayey,
The soil rigidity can be improved by reload release. (7) According to the seventh aspect of the present invention, it is possible to construct an abutment portion having a very high deformation performance and a very small compression settlement with a simple configuration. (8) According to the eighth aspect of the invention, it is possible to greatly reduce the compression settlement of the embankment due to the building load with a simple configuration.

(9) According to the ninth aspect of the invention, it is possible to reduce the initial deformation and residual change amount of the ballast caused by running the train with a simple configuration, and to reduce the load and cost for maintenance. (10) According to the invention of claim 10, the reinforcement of the present invention by omitting the roadbed concrete, asphalt pavement, granulated stone, and the like disposed below the slab plate used in the conventional slab railway track. A simple structure in which only the slab plate is disposed on the earth structure can be provided.

Thus, the present invention provides a lower horizontal loading plate,
With a simple structure such as vertical tendon, upper horizontal reinforcement, etc., it is possible to remarkably improve the deformation performance of soil and reclaimed material, and it can be widely applied to embankments or railway tracks where settlement restrictions are severe, The effect it brings is significant.

[Brief description of the drawings]

FIG. 1 is a sectional view of a reinforced earth structure showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a stress state of soil.

FIG. 3 is a diagram illustrating a relationship between stress and strain in soil when loading is performed without performing preloading.

FIG. 4 is an explanatory diagram of a stress-strain relationship in soil when a preload Tp is applied.

FIG. 5 is a schematic view of a resistance mechanism between soil and a vertical tendon.

FIG. 6 is a diagram showing the relationship between soil stress and strain when a part of the preload is released and reloading is performed.

FIG. 7 is a cross-sectional view of an abutment in which the method of constructing a reinforcing earth body of the present invention is applied to an abutment.

FIG. 8 is a sectional view of a building foundation in which the method for constructing a reinforced soil body of the present invention is applied to a building foundation.

FIG. 9 is a cross-sectional view of a railway track base in which the method for constructing a reinforced soil body of the present invention is applied to a railway track base having a ballast ballast.

FIG. 10 is a cross-sectional perspective view of a slab railroad track foundation in which the method of constructing a reinforced soil body of the present invention is applied to a slab railroad track base.

[Explanation of symbols]

1, 10, 20, 30, 40 Ground 2, 14, 22, 42 Embankment 3 Lower horizontal loading plate 4 Upper horizontal loading plate 5, 17 Vertical tendon 6 Fixing jig 7, 13 Horizontal tension reinforcing material 8 Compression spring of soil Reaction force 9 Compression spring reaction force of vertical tension member 11 Wall concrete 12 Sandbag 15, 21, 41 Bottom reinforced concrete plate (lower horizontal loading plate) 16 Abutment (upper horizontal loading plate) 18 PVC pipe 19 girder 23 PC steel rod (vertical) 25) Upper surface reinforced concrete plate 26 Building 31 Roadbed concrete 31A Roadbed concrete upper surface 32,43 Screw-shaped mounting bracket 33,44 Reinforcing bar (vertical tendon) 34 Ballast ballast 35 Concrete sleeper 35A Concrete sleeper lower surface 36,47 Rail 37,46 Nut 45 slab

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) E02D 17/18 E02D 3/00 102 E02D 3/02 103

Claims (10)

(57) [Claims] (A) placing a lower horizontal loading plate on the ground; (b) stacking the embankment to a predetermined height on the lower horizontal loading plate; and (c) placing an upper horizontal loading plate on the upper surface of the embankment to be stacked. And (d) connecting the lower horizontal loading plate and the upper horizontal loading plate with a vertical tendon to apply a preload to the embankment, and then applying the preload to the upper horizontal loading plate with the preload slightly released. A method of constructing a reinforced earth body, comprising fixing a vertical tendon. 2. A method for constructing a reinforced earth body according to claim 1.
And the embankment to be stacked is clayey soil.
How to build. 3. The method for constructing a reinforced earth body according to claim 1, wherein when the compressive strength of the piled-up embankment is insufficient, a tensile reinforcing material is arranged in a horizontal direction in accordance with the rolling pressure of the embankment. How to build a reinforced earth body. (A) a lower horizontal loading plate disposed on the ground; (b) a vertical tendon member having one end fixed to the lower horizontal loading plate; and (c) stacked on the lower horizontal loading plate. An embankment; (d) an upper horizontal loading plate disposed on the upper surface of the pile to be stacked; and (e) a preload acting on the embankment by connecting the lower horizontal loading plate and the upper horizontal loading plate with the vertical tendons. Means for fixing the vertical tendon to the upper horizontal loading plate with the preload slightly released after the preloading. 5. A lower horizontal loading plate disposed on the ground; a vertical tendon member having one end fixed to the lower horizontal loading plate; and c) embankment on the lower horizontal loading plate. An embankment having a tensile reinforcement arranged horizontally in accordance with the rolling pressure; (d) an upper horizontal loading plate arranged on the upper surface of the stacked embankment; (e) the lower horizontal loading plate and the upper horizontal loading Means for connecting a plate with the vertical tendon to apply a preload to the embankment, and then fixing the vertical tendon to the upper horizontal loading plate with the preload slightly released. Stuff. 6. The reinforcing earth structure according to claim 4 or 5.
In the above, cohesive soil is used as the embankment to be piled up
Reinforced earth structure. 7. The reinforced earth structure according to claim 4, 5 or 6, wherein the lower horizontal loading plate is a reinforced concrete base plate and the upper horizontal loading plate is a small abutment. Stuff. 8. The reinforced earth structure according to claim 4, 5 or 6, wherein the lower horizontal loading plate is a reinforced concrete plate on a bottom surface, the upper horizontal loading plate is a reinforced concrete plate on a bottom surface, and the vertical tension member is a PC steel rod. Reinforced earth structure used for the foundation of a building. 9. The reinforced earth structure according to claim 4, 5 or 6, wherein the lower horizontal loading plate is a roadbed concrete or a pressure receiving plate, the upper horizontal loading plate is a concrete sleeper, and the vertical tension member is a reinforcing bar. Reinforced earth structure used for the base of railway track of ballast ballast. 10. The slab railway according to claim 4, wherein the lower horizontal loading plate is a reinforced concrete bottom plate, the upper horizontal loading plate is a slab plate, and the vertical tension member is a reinforcing bar. Reinforced earth structure used for track foundation.