CN211227880U - Expansive soil limited deformation anti-upwarp foundation structure - Google Patents

Abstract

The utility model discloses a confined foundation structure that warp is prevented to inflation soil, foundation structure includes flexible bed course, raft and stretches into the reinforcement stake in the foundation soil, the flexible bed course sets up on the top surface of foundation soil, the raft is located flexible bed course top, just the raft simultaneously with the flexible bed course with the reinforcement stake is connected. The utility model discloses the foundation structure has not only effectively guaranteed to bear and has subsided the control effect, has still avoided encircleing the disease on the inflation that leads to roadbed structure to produce because of the foundation soil.

Description

Expansive soil limited deformation anti-upwarp foundation structure

Technical Field

The utility model relates to a ground treatment technical field, in particular to bloated soil finite deformation prevents foundation structure that arches.

Background

The expansive soil has the characteristics of strong water loss shrinkage and strong water absorption expansion, and if the expansive soil in the foundation soil absorbs water and expands, an upwarp disease is generated on a roadbed structure on the foundation structure, so that the normal operation of a high-speed railway is influenced.

For low embankments and excavation cuts, foundation structures of high speed railways with expansive soils are typically treated by: the foundation bed is filled with qualified fillers, the foundation structure is processed by adopting a CFG (Cement Fly-ash gravel) pile and pile cap combined with a broken stone cushion layer clamping and paving geogrid structure, the method has good effect of preventing the subgrade from settling, the cost is low, but expansive soil among the CFG piles is easy to expand and deform when meeting water, so that the cushion layer, the filling soil and a roadbed surface generate an upwarp disease under the expansion action, and the upwarp prevention requirement of the subgrade structure under the condition of strong expansion cannot be met. Therefore, although the scheme has a good effect of preventing subgrade settlement, the anti-arching capability is insufficient and the measures are weak.

SUMMERY OF THE UTILITY MODEL

In order to solve the technical problem, the embodiment of the utility model provides a limited deformation of swelling soil prevents foundation structure that arches.

In order to achieve the above purpose, the technical scheme of the utility model is realized like this:

the embodiment of the utility model discloses foundation structure that inflation soil finite deformation prevented upwarping, foundation structure includes flexible bed course, raft and stretches into to have reinforcing pile in the foundation soil of inflation soil, the flexible bed course sets up on the top surface of foundation soil, the raft is located flexible bed course top, just the raft simultaneously with the flexible bed course with reinforcing pile connects.

In the above scheme, the foundation structure further comprises a reinforcing structure, one end of the reinforcing structure is inserted into the reinforcing piles, and the other end of the reinforcing structure is inserted into the raft.

In the above scheme, the end of the reinforcing structure connected with the reinforcing piles is in a cone shape with the inner diameter gradually decreasing from top to bottom, and the end of the reinforcing structure connected with the raft is in a frustum shape with the inner diameter gradually decreasing from top to bottom.

In the above scheme, the length of the reinforcing structure is smaller than that of the reinforcing pile.

In the above scheme, the raft is of a reinforced concrete structure.

In the above scheme, the reinforcing steel bars of the raft are connected with the reinforcing structure, and the reinforcing steel bars of the raft are connected with the flexible cushion layer.

In the above scheme, the reinforcing piles are CFG piles.

In the above scheme, the reinforcing structure is made of steel.

In the above scheme, the reinforcing structure is a reinforcement cage.

In the above scheme, the flexible cushion layer is made of porous material or rubber.

The utility model provides a limited deformation of inflation soil prevents foundation structure that arches, reinforcement pile are used for consolidating foundation soil, guarantee foundation soil's intensity, have improved the effect to foundation structure settlement control. The roadbed structure is arranged on the raft plates, and the raft plates are used for bearing loads from the roadbed structure and transmitting the loads to the reinforcing piles. The flexible cushion layer between the raft and the top surface of the foundation soil counteracts the expansion of the foundation soil by deforming. To sum up, the utility model discloses foundation structure has not only effectively guaranteed to bear and has subsided the control effect, has still avoided encircleing the disease on the inflation that leads to roadbed structure to produce because of the foundation soil.

Drawings

Fig. 1 is an alternative structural schematic diagram of a foundation structure in the embodiment of the present invention;

fig. 2 is an enlarged view of a point a in fig. 1.

Reference numerals:

a reinforcing pile 10; a flexible cushion layer 20; a raft plate 30; a reinforcing structure 40; a side form 50; a roadbed structure 100; a ramp 110; a running water slope 120; a ground line 130.

Detailed Description

In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention are combined below to clearly and completely describe the technical solution of the embodiments of the present invention. It is to be understood that the embodiments described are only some of the embodiments of the present invention, and not all of them. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention, belong to the scope of protection of the invention.

In the description of the present invention, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on the orientation or positional relationships shown in fig. 1.

The embodiment of the utility model provides a confined foundation structure that warp is prevented upwarping by inflation soil, foundation structure include flexible bed course 20, raft 30 and stretch into the reinforcement stake 10 in the foundation soil that has inflation soil, and flexible bed course 20 sets up on the top surface of foundation soil, and raft 30 is located flexible bed course 20 top, and raft 30 is connected with flexible bed course 20 and reinforcement stake 10 simultaneously.

As shown in fig. 1, a plurality of reinforcing piles 10 are arranged in the form of pile groups of squares or regular triangles, without limitation. The reinforcing pile 10 is used for reinforcing foundation soil, so that the strength of the foundation soil is ensured, and the effect of controlling the settlement of the roadbed structure 100 is improved. The tops of the reinforcing piles 10 are exposed on the top surface of the foundation soil, the raft 30 is a rigid structure, the roadbed structure 100 is located on the raft 30, and the raft 30 is used for bearing the load from the roadbed structure 100 and transmitting the load to the reinforcing piles 10. When the swelling soil in the foundation soil absorbs water and deforms, the deformed foundation soil can press the flexible cushion layer 20 to deform, and the deformation of the flexible cushion layer 20 can effectively offset the deformation of the foundation soil, so that the damage of upwarp of the roadbed structure 100 is effectively avoided.

In addition to being able to counteract the deformation caused by a certain arching effect, the compliant cushion 20 is also able to produce a small amount of deformation due to its own weight to accommodate the structure of the raft 30 etc. located above it.

Preferably, the compliant pad 20 has a compression modulus of 1 to 3MPa and a thickness of 0.1 to 0.3 m. The material of the flexible cushion layer 20 includes, but is not limited to, loose porous material, or rubber. For example, the compliant pad 20 is a polystyrene foam board, glass wool, styrene butadiene rubber, or the like.

The embodiment of the utility model provides an in "limited deformation" indicate the condition that the volume of deformation is less than 0.1m that arches on the roadbed structure 100 that leads to because of the inflation of bentonite. Because high-speed railway is comparatively strict to roadbed structure 100 deformation requirement, adopts the utility model discloses corresponding roadbed structure 100 requirement can be satisfied to the foundation structure of embodiment.

In some embodiments of the present invention, the foundation structure further comprises a reinforcing structure 40, one end of the reinforcing structure 40 is inserted into the reinforcing pile 10, and the other end is inserted into the raft 30.

The reinforcing structure 40 further reinforces the mechanical properties of the foundation structure. Specifically, the reinforcing structure 40 may be inserted into the reinforcing piles 10 and the raft 30 by anchoring, so as to enhance the integrity among the reinforcing piles 10, the raft 30, the flexible cushion 20 and the reinforcing structure 40, and further improve the bending resistance and the compression resistance of the foundation structure.

Further, the end of the reinforcing structure 40 connected to the reinforcing piles 10 is tapered such that the inner diameter thereof gradually decreases from top to bottom, and the end of the reinforcing structure 40 connected to the raft 30 is frustum-shaped such that the inner diameter thereof gradually decreases from top to bottom.

As shown in fig. 1 and 2, the conical bottom of the reinforcing structure 40 is easier to insert into for construction, and the frustum shape with large top and small bottom of the reinforcing structure 40 can be better anchored into the raft 30, so that the connection strength between the raft 30 is increased.

The material of the reinforcing structure 40 is preferably steel, such as steel bar. It is understood that other alloys may be used for the reinforcing structure 40, or materials that may be substituted for steel reinforcement in future technologies. For example: the reinforcing structure 40 may be made of glass fiber, carbon fiber, or the like.

Without limitation, the reinforcing structure 40 is a cage of rebar, i.e., a rebar cage.

Preferably, the length of the reinforcing structure 40 is less than the length of the reinforcing pile 10. As shown in FIG. 1, the reinforcing structure 40 is disposed at the top of the reinforcing pile 10 and has a length of 2-5 m. The reinforcing structure 40 can reduce the use amount of reinforcing steel bar materials on the basis of meeting the mechanical performance of the foundation structure, and has better economic effect.

In some embodiments of the present invention, the rafts 30 are of reinforced concrete structure.

Further, the reinforcing bars of the rafts 30 are connected with the reinforcing structures 40, and the reinforcing bars of the rafts 30 are connected with the flexible cushion 20. Specifically, during construction, the reinforcing steel bars of the raft 30 are bound on the flexible cushion layer 20, and meanwhile, the reinforcing steel bars of the raft 30 are also connected with the reinforcing steel bars of the reinforcing structure 40 positioned at the top of the reinforcing pile 10, and then concrete is poured to form the raft 30. The integrality of the reinforcing piles 10, the flexible cushion layer 20, the raft 30 and the reinforcing structure 40 is further improved, and the bending resistance and the compression resistance of the integral structure formed by the reinforcing piles 10, the flexible cushion layer 20, the raft 30 and the reinforcing structure 40 are ensured.

In some embodiments of the present invention, the reinforcing pile 10 is a reinforced concrete bored pile.

In other preferred embodiments of the present invention, the reinforcing piles 10 are preferably CFG piles. Compared with the reinforced concrete bored pile, the CFG pile has smaller distance between the piles, the CFG pile is low in cost, the using amount of reinforcing steel bars is reduced, and the cost is further reduced. CFG stake, raft 30 and additional strengthening 40 bear the moment of flexure jointly, and the stake length of CFG stake is 10 ~ 25m generally, and raft 30 thickness is 0.4 ~ 0.6 m.

The embodiment of the utility model provides a still provides a foundation structure's construction method, and this construction method is applicable to any kind of foundation structure of above-mentioned. The construction method comprises the following steps:

removing the foundation soil until the top surface of the foundation soil is positioned below the pile top of the reinforcing pile 10;

laying a flexible cushion 20 on the top surface of the foundation soil;

arranging a raft 30 on the flexible cushion layer 20, and simultaneously connecting the raft 30 with the flexible cushion layer 20 and the reinforcing piles 10.

Taking the construction of the CFG pile as an example, the construction is measured and set off on site, the positioning and elevation of each point such as the CFG pile and the raft 30 are determined, and the foundation soil is dug for the first time to a position about 0.15m below the designed pile top elevation. And (3) adopting a long spiral drilling machine to form holes, wherein the hole diameter is 0.4-0.6 m, the pile spacing is 1.5-2.0 m, the pile length is generally 10-25 m, the square or regular triangle is arranged, and pouring CFG pile hole concrete.

When the foundation structure further includes the reinforcing structure 40, the reinforcing structure 40 is inserted before the reinforcing piles 10 are solidified, and the top ends of the reinforcing structure 40 are exposed outside the reinforcing piles 10.

In particular, the reinforcing structure 40 is a reinforcement cage. Insert the steel reinforcement cage in CFG pile top according to back dowel bar mode before the concrete initial set and fix, the steel reinforcement cage height is 2 ~ 5m, and the totality is cylindricly. After inserting the steel reinforcement cage, adopt the vibrator to vibrate the loose concrete of CFG pile head portion closely knit to clear away and level the pile head with exceeding the concrete of CFG pile top elevation, maintenance concrete is as an organic whole with the consolidation hardening of reinforcement pile 10 to the steel reinforcement cage, then lays above-mentioned flexible bed course 20.

The process of laying the compliant backing layer 20 is generally: and excavating part of foundation soil again, specifically, cleaning and transporting temporary field mound brought out during pore-forming of the CFG pile, and cleaning and excavating the top surface of the foundation soil between the piles to a certain depth (about 0.2-0.4 m) below the top of the CFG pile. Then, a flexible cushion layer 20 is laid on the top surface of the foundation soil, the thickness of the flexible cushion layer 20 is 0.1-0.3 m, and the compression modulus is 1-3 MPa.

When the rafts 30 are of reinforced concrete structure, the construction method further comprises:

binding reinforcing steel bars of the raft plate 30 on the flexible cushion layer 20, and connecting the reinforcing steel bars of the raft plate 30 with the reinforcing structure 40 exposed outside;

and pouring concrete of the raft plates 30 until the reinforcing structures 40 exposed outside are positioned in the concrete.

Further, the reinforcing steel bars of the raft 30 are bound on the bottom die of the flexible cushion layer 20, the detachable side dies 50 are arranged on the periphery of the bottom die through the supports, concrete is poured on the raft 30, and the thickness of the raft 30 is 0.4-0.6 m. When concrete is cast in place, the top of the CFG pile is about 0.1m and the top of the reinforcing structure 40 is anchored into the raft 30 to form an integral structure, and a certain anti-upwarping effect is formed by utilizing the compressibility of the flexible cushion layer 20 at the bottom of the raft 30.

After the above process is completed, the roadbed structure 100 can be set. Specifically, it includes filling roadbed filling on the raft 30.

Specifically, the construction of a high-speed railway is taken as an example. And filling the roadbed filling according to the high-speed railway standard. Firstly, filling foundation bed bottom filler according to a foundation bed bottom compaction standard, arranging running water slopes 120 on the top surfaces of the foundation bed bottom towards two sides, and preferably selecting the gradient coefficient of the running water slopes 120 to be 4%. And then, filling the bottom layer filler of the foundation bed according to the standard foundation bed surface layer compaction, wherein the shape of the top surface of the roadbed structure 100 is set according to the high-speed railway track type.

As shown in fig. 1, the roadbed structure 100 has a substantially trapezoidal shape, and the slopes 110 of both sides of the roadbed structure 100 preferably have a slope of 1: 15. The ground line 130 is located on the rafts 30.

The features disclosed in the several foundation structure construction methods or foundation structure embodiments provided in the present application may be combined arbitrarily without conflict to arrive at new method embodiments or apparatus embodiments.

Other structures and operations of the foundation structure according to embodiments of the present invention are understood and easily implemented by those skilled in the art, and thus will not be described in detail.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention.

Claims (10)

1. The utility model provides a confined foundation structure that warp is prevented to inflation soil, its characterized in that, foundation structure includes flexible bed course, raft and stretches into and has reinforcement stake in the foundation soil of inflation soil, the flexible bed course sets up on the top surface of foundation soil, the raft is located flexible bed course top, just the raft simultaneously with the flexible bed course with reinforcement stake is connected.

2. A foundation structure according to claim 1, further comprising a reinforcing structure inserted at one end into the reinforcing piles and at the other end into the rafts.

3. The foundation structure of claim 2, wherein the end of the reinforcing structure connected to the reinforcing piles is tapered with an inner diameter gradually decreasing from top to bottom, and the end of the reinforcing structure connected to the rafts is frustum-shaped with an inner diameter gradually decreasing from top to bottom.

4. A foundation structure according to claim 2, wherein the length of the reinforcing structure is less than the length of the reinforcing piles.

5. A foundation structure according to claim 3, wherein the rafts are of reinforced concrete construction.

6. A foundation structure according to claim 5, wherein the tendons of the rafts are connected to the reinforcing structure and the tendons of the rafts are connected to the compliant pad layer.

7. A foundation structure according to claim 1, wherein said reinforcing piles are CFG piles.

8. A foundation structure according to claim 2, wherein said reinforcing structure is steel.

9. A foundation structure according to claim 8, wherein the reinforcing structure is a reinforcement cage.

10. A foundation structure as claimed in claim 1, wherein the compliant pad layer is of a porous material or rubber.

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