CN113073631B

CN113073631B - Construction method for deep and soft soil layer of highway

Info

Publication number: CN113073631B
Application number: CN202110395044.9A
Authority: CN
Inventors: 彭龙; 黄增荣; 李芳�; 旷小振; 游专
Original assignee: Hunan Yingsheng Transportation Construction Engineering Co ltd
Current assignee: Hunan Yingsheng Transportation Construction Engineering Co ltd
Priority date: 2021-04-13
Filing date: 2021-04-13
Publication date: 2022-07-05
Anticipated expiration: 2041-04-13
Also published as: CN113073631A

Abstract

The application relates to a construction method of a deep soft soil layer of a highway, belonging to the technical field of soft soil foundation construction and comprising the following steps: firstly, anchoring a prefabricated tubular pile into a foundation through pile pressing equipment, then anchoring a consolidation pile and the prefabricated tubular pile into the foundation in a staggered manner through the pile pressing equipment, so that water in a soft soil foundation enters the prefabricated tubular pile, then discharging the water in the prefabricated tubular pile, and finally pouring concrete into the prefabricated tubular pile; the precast tubular pile of (2) is prefabricated by the concrete that permeates water and forms, and the one end of precast tubular pile is provided with the awl point, is provided with the support frame in the precast tubular pile, is provided with the drain pipe along length direction in the precast tubular pile, and the drain pipe is worn to establish on the support frame, and the bottom of drain pipe is supported tightly on the inner wall of awl point, and the bottom of drain pipe is provided with a plurality of water drainage tank that run through the pipe wall, and the drain pipe concreties the stake and includes the sleeve pipe and fills in the intraductal filler of cover. This application has the effect of shortening the construction cycle of drainage consolidation construction.

Description

Construction method for deep and soft soil layer of highway

Technical Field

The application relates to the technical field of soft soil foundation construction, in particular to a construction method for a deep and soft soil layer of a highway.

Background

The property of the soft soil foundation is different from ground to ground, the unpredictability is high, quality accidents can happen due to slight negligence in the design and construction processes, and great harm is caused to the highway subgrade. When the soil meets soft and weak-viscosity soil, the soil has the characteristics of large water content, high compressibility, low shear strength, poor water permeability and the like, and because the consolidation speed is low, uneven settlement is often generated, the flatness of the road surface is affected, and even the whole road surface is damaged, so the soft soil is usually required to be reinforced.

The common treatment method for reinforcing the soft soil foundation is a drainage consolidation construction method, and when drainage is performed by adopting a drainage consolidation method, the foundation is generally loaded and pre-pressed, so that foundation settlement can be completed in advance, and the bearing capacity of the foundation is improved by consolidating foundation soil. When the loading prepressing is adopted, in order to avoid the instability caused by the plastic deformation of the foundation, the graded loading, the loading speed control and the loading load each time are required to be adapted to the strength increasing speed of the foundation.

In view of the above-described related art, the inventors believe that when the construction is performed by the construction loading pre-compaction method, although the settlement after the construction can be effectively reduced, the loading needs to be performed in stages, and the construction time is long.

Disclosure of Invention

In order to shorten the construction period of drainage consolidation construction, the application provides a construction method for a deep and soft soil layer of a highway.

The application provides a construction method for a deep soft soil layer of a highway, which adopts the following technical scheme:

a construction method for a deep and soft soil layer of a highway comprises the following steps:

step 1, cleaning and leveling a field;

step 2, anchoring the prefabricated tubular pile into the foundation through pile pressing equipment;

step 3, anchoring the consolidation piles and the precast tubular piles into the foundation in a staggered manner through pile pressing equipment, and enabling water in the soft soil foundation to enter the precast tubular piles through extrusion force between the precast tubular piles and the consolidation piles;

step 4, discharging water in the precast tubular pile;

step 5, pouring concrete into the precast tubular pile;

precast tubular pile form by the precast concrete that permeates water, precast tubular pile's one end is provided with the awl point, be provided with the support frame in the precast tubular pile, be provided with the drain pipe along length direction in the precast tubular pile, the drain pipe is worn to establish on the support frame, the bottom of drain pipe is supported tightly on the inner wall of awl point, and the bottom of drain pipe is provided with a plurality of water drainage tank that run through the pipe wall, the drain pipe concreties the stake and includes the sleeve pipe and pack in the intraductal filler of cover.

Through adopting above-mentioned technical scheme, when carrying out the drainage consolidation to deep soft soil layer, water through precast tubular pile and consolidation extrusion force between the stake makes in the soft soil foundation enters into precast tubular pile, can discharge the water in the foundation on the one hand, and on the other hand can make precast tubular pile and consolidation density between the stake increase in order to improve the bearing capacity through the extrusion, and the precast tubular pile is the pouring concrete in the back is accomplished in the drainage, makes precast tubular pile can bear great shearing force, reduces the risk that the foundation appears sliding.

Optionally, in step 3, when the consolidation piles are arranged, the construction sequence is that the construction is performed from two sides of the roadbed to the middle of the roadbed in sequence.

By adopting the technical scheme, the protective layers with high density can be formed on the two sides of the roadbed in the construction process, and the soft soil of the roadbed is not easy to collapse towards the two sides when the consolidation piles are constructed in the middle of the roadbed subsequently.

Optionally, the step 3 specifically includes the following steps:

step 31, pressing the sleeve into the foundation through a pile driver;

and 32, injecting the filler into the tubular pile, and tamping the filler in the tubular pile.

Through adopting above-mentioned technical scheme, the sleeve pipe is inserted in soil relatively easily, through to the intraductal filler of injecting of cover, when tamp the filler, can increase sheathed tube bulk strength on the one hand, and in the ground can be impressed to the intraductal original soil of on the other hand cover, extrudees the soil of the deep position of ground.

Optionally, after step 5 is completed, the method further includes the following steps:

and 6, excavating the soil layer on the upper surface of the roadbed, filling the soil layer with a mixture of slaked lime and fly ash, and compacting the filled mixture of slaked lime and fly ash by using a construction machine.

By adopting the technical scheme, because the compaction effect of the surface soil is relatively poor, the surface layer is dug and filled with the mixture of the slaked lime and the fly ash, and the bearing capacity of the surface layer of the roadbed can be improved after compaction.

Optionally, the pouring manner into the precast tubular pile in step 5 is specifically to pour concrete into the precast tubular pile from the top end of the drain pipe, so that the concrete enters the precast tubular pile through the drain pipe, and the drain pipe is moved upward in the concrete pouring process, and when the precast tubular pile is filled with concrete, the drain pipe is separated from the precast tubular pile.

By adopting the technical scheme, on one hand, the concrete is poured into the precast tubular pile through the drain pipe, so that the concrete can be filled from the bottom of the precast tubular pile, and the risk of forming a cavity in the pouring process of the concrete is reduced; on the other hand, the drain pipe can be taken out for recycling, and the use cost is low.

Optionally, the outer wall of the drain pipe is provided with a guide groove in a winding manner, the guide groove extends along the length direction of the drain pipe, the support frame is provided with a guide block, and the guide block is connected in the guide groove in a sliding manner.

Through adopting above-mentioned technical scheme, when the in-process of pouring concrete upwards takes out the drain pipe, under the sliding fit effect of guide block and guide way, the drain pipe can be along circumference reciprocating swing, makes the distribution that the concrete can be comparatively even in precast tubular pile.

Optionally, be provided with a plurality of stirring pieces along circumference on the outer wall of drain pipe bottom, stirring piece and the crisscross interval setting of water drainage tank.

Through adopting above-mentioned technical scheme, when the drain pipe takes place to rotate, the stirring piece can promote the concrete, makes the port and the water drainage tank exhaust concrete from the drain pipe can be comparatively even distribution in precast tubular pile.

Optionally, the top end fixedly connected with adapter sleeve of drain pipe, the cover is equipped with the hoisting ring on the adapter sleeve, the hoisting ring rotates with the adapter sleeve along circumference to be connected, be provided with the lug on the hoisting ring.

Through adopting above-mentioned technical scheme, the adapter sleeve can be convenient for carry concrete's pipe connection to the drain pipe on, at the in-process through hoisting ring hoist and mount drain pipe, can rotate relatively between drain pipe and the hoisting ring, even the drain pipe can rotate at the in-process that goes up and down, hoist and mount rope and hoisting ring also can be comparatively stable.

In summary, the present application includes at least one of the following beneficial technical effects:

1. the prefabricated pipe pile and the consolidation pile are anchored into the soft and thick soil foundation, deep soft and thick soil is directly extruded, water in the soft and thick soil can enter the prefabricated pipe pile, and the construction period is short when drainage and fixation are carried out;

2. the soft and thick soil is reinforced by combining the consolidation pile and the precast tubular pile, so that the vertical rigidity of the foundation soil is increased;

3. the drain pipe can be with the water discharge in the precast tubular pile, can assist again to carry out pouring of concrete, can also retrieve after finishing using, and it is comparatively convenient to use.

Drawings

Fig. 1 is a quarter sectional view of a precast tubular pile in example 1 of the present application;

FIG. 2 is a schematic view of the structure of the drain pipe of FIG. 1;

FIG. 3 is an enlarged partial schematic view of A of FIG. 1;

fig. 4 is an exploded view of the connecting sleeve of fig. 1;

FIG. 5 is a quarter sectional view of a consolidated pile according to example 1 of the present application;

fig. 6 is a cross-sectional view of a roadbed in the width direction in the embodiment 2 of the application;

fig. 7 is a plan view of a roadbed in embodiment 2 of the present application.

Description of the reference numerals: 1. prefabricating a tubular pile; 2. a conical tip; 3. a support frame; 31. a support bar; 32. a support block; 33. a guide block; 4. a guide groove; 5. a drain pipe; 6. a water discharge tank; 7. a stirring sheet; 8. connecting sleeves; 9. a threaded hole; 10. a limiting groove; 11. hoisting a ring; 12. lifting lugs; 13. consolidating the piles; 14. a sleeve; 15. a baffle plate; 17. and (7) roadbed.

Detailed Description

The present application is described in further detail below with reference to figures 1-7.

Example 1

Referring to fig. 1, this embodiment discloses a precast tubular pile 1, precast tubular pile 1 has the concrete that permeates water to prefabricate and forms, and precast tubular pile 1's one end is provided with awl point 2, and precast tubular pile 1 is cylindrical tubulose, and awl point 2 is conical, and awl point 2 and precast tubular pile 1 integrated into one piece.

Referring to fig. 1, a support frame 3 is arranged in an inner cavity of a precast tubular pile 1, the support frame 3 is precast in the precast tubular pile 1, a plurality of groups of the support frames 3 are arranged in the precast tubular pile 1 along the length direction of the precast tubular pile 1, the number of the support frames 3 is determined according to the length of the precast tubular pile 1, and the distance between the adjacent support frames 3 is 1.5m-2 m.

Referring to fig. 2 and 3, each support frame 3 includes two support rods 31 symmetrically arranged, one end of each support rod 31 is fixed in the precast tubular pile 1, the other end of each support rod is provided with an arc-shaped support block 32, a drain pipe 5 is arranged between the two support blocks 32, the arc surface of each support block 32 is attached to the outer wall of the corresponding drain pipe 5, the drain pipe 5 is arranged along the length direction of the precast tubular pile 1, and the support blocks 32 abut against the outer wall of the drain pipe 5 to position the drain pipe 5.

Be provided with guide way 4 along length direction on drain pipe 5's the outer wall, guide way 4 is sine wave form sinuous extension on drain pipe 5, and supporting shoe 32 is fixed with guide block 33 towards the cambered surface of drain pipe 5, and one side that is close to drain pipe 5 of guide block 33 is the arc, and guide block 33 sliding connection is in guide way 4. When the drain moves in the axial direction, the guide block 33 slides in the guide groove 4 to guide the drain pipe 5 so that the drain pipe 5 can reciprocate in the circumferential direction.

The bottom of drain pipe 5 supports tightly on the inner wall of awl point 2, and the bottom of drain pipe 5 is provided with a plurality of water drainage tank 6 that run through the pipe wall, is provided with a plurality of stirring pieces 7 along circumference on the outer wall of drain pipe 5 bottom, and stirring piece 7 sets up with water drainage tank 6 crisscross interval.

Referring to fig. 4, a connection sleeve 8 is fixedly connected to the top end of the drain pipe 5. One end of the connecting sleeve 8, which is far away from the water discharge pipe 5, is provided with a threaded hole 9 for being connected with a concrete conveying pipeline, a limiting groove 10 is formed in the outer wall of the connecting sleeve 8 along the circumferential direction, a hoisting ring 11 is arranged in the limiting groove 10, the hoisting ring 11 is rotatably connected with the connecting sleeve 8 along the circumferential direction, and a lifting lug 12 is arranged on the hoisting ring 11.

Referring to fig. 5, the present embodiment further discloses a consolidation pile 13, where the consolidation pile 13 includes a casing 14 and a filler filled in the casing 14, the casing 14 is a steel pipe, and the filler is a mixture of slaked lime and fly ash mixed in a ratio of 1: 1. The top end of the sleeve 14 is provided with a stop 15 to facilitate the pressing of the sleeve 14 into the ground by a press-fitting machine.

Example 2

Referring to fig. 6 and 7, an embodiment of the application discloses a construction method for a deep and soft soil layer of a highway, which adopts a precast tubular pile 1 and a consolidation pile 13 in embodiment 1, and comprises the following steps:

step 1, cleaning and leveling a field, leveling the field by matching an excavator and a bulldozer, and primarily compacting the surface of a soil layer under the rolling of construction machinery and a transport vehicle;

step 2, anchoring the precast tubular pile 1 into the foundation through pile pressing equipment until the top end of the precast tubular pile 1 is 10-20cm away from the ground;

anchoring the consolidation piles 13 into the foundation through pile pressing equipment, alternately arranging the consolidation piles 13 and the precast tubular piles 1 along the width direction of the roadbed 17, sequentially constructing from two sides of the roadbed 17 to the middle part of the roadbed 17 in the construction sequence when arranging the consolidation piles 13, and enabling water in the soft soil foundation to enter the precast tubular piles 1 through the extrusion force between the precast tubular piles 1 and the consolidation piles 13;

anchoring the consolidation piles 13 into the ground particularly comprises the following steps:

step 31, pressing the sleeve 14 into the foundation by a pile driver;

and 32, mixing the slaked lime and the fly ash according to the ratio of 1:1, then injecting the mixture into the pipe pile, and tamping the filler in the pipe pile.

Step 4, connecting pumping equipment to the top end of the drain pipe 5, and draining water in the precast tubular pile 1 through the drain pipe 5;

and 5, connecting the connecting sleeve 8 with a concrete conveying pipeline, enabling the concrete to enter the precast tubular pile 1 through the water discharge pipe 5, lifting the lifting ring 11 upwards through lifting equipment in the concrete pouring process, driving the water discharge pipe 5 to move upwards through the lifting ring 11, and separating the water discharge pipe 5 from the precast tubular pile 1 when the precast tubular pile 1 is filled with the concrete.

And 6, excavating the soil layer on the upper surface of the roadbed 17, filling the soil layer with a mixture of slaked lime and fly ash, and compacting the filled mixture of slaked lime and fly ash by using a construction machine.

The implementation principle of the construction method for the deep and soft soil layer of the highway in the embodiment of the application is as follows: consolidate soft thick soil through consolidation stake 13 and precast tubular pile 1's combination, increased the vertical rigidity of foundation soil, also can extrude subbase soil layer simultaneously, make the water in the ground enter into precast tubular pile 1 more easily in to carry out the drainage. In addition, lime and fly ash belong to light materials, so that the dead weight of the reinforced composite soil layer is increased slightly, and the stress on the soil layer below the end face of the precast tubular pile 1 is reduced.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. A construction method of a deep and soft soil layer of a highway is characterized by comprising the following steps: the method comprises the following steps:

step 1, cleaning and leveling a field;

step 2, anchoring the precast tubular pile (1) into the foundation through pile pressing equipment;

step 3, anchoring the consolidation pile (13) and the precast tubular pile (1) into the foundation in a staggered manner through pile pressing equipment, and enabling water in the soft soil foundation to enter the precast tubular pile (1) through extrusion force between the precast tubular pile (1) and the consolidation pile (13);

step 4, discharging water in the precast tubular pile (1);

step 5, pouring concrete into the precast tubular pile (1);

the prefabricated pipe pile (1) is prefabricated by pervious concrete, a cone tip (2) is arranged at one end of the prefabricated pipe pile (1), a support frame (3) is arranged in the prefabricated pipe pile (1), a drain pipe (5) is arranged in the prefabricated pipe pile (1) along the length direction, the drain pipe (5) penetrates through the support frame (3), the bottom end of the drain pipe (5) is tightly abutted to the inner wall of the cone tip (2), a plurality of drain grooves (6) penetrating through the pipe wall are formed in the bottom end of the drain pipe (5), and the consolidation pile (13) comprises a sleeve (14) and filler filled in the sleeve (14);

pouring concrete into the precast tubular pile (1) in the step 5 specifically comprises pouring the concrete from the top end of the drain pipe (5), so that the concrete enters the precast tubular pile (1) through the drain pipe (5), moving the drain pipe (5) upwards in the process of pouring the concrete, and separating the drain pipe (5) from the precast tubular pile (1) when the precast tubular pile (1) is filled with the concrete;

meandering to be established on the outer wall of drain pipe (5) has seted up guide way (4), the length direction of drain pipe (5) is followed in guide way (4) extends, be provided with guide block (33) on support frame (3), guide block (33) sliding connection is in guide way (4).

2. The construction method for the deep and soft soil layer of the highway according to claim 1, which is characterized in that: in the step 3, when the consolidation piles (13) are arranged, the construction sequence is that the construction is performed from two sides of the roadbed (17) to the middle part of the roadbed (17) in sequence.

3. The construction method of the deep and soft soil layer of the highway according to claim 2, which is characterized in that: the step 3 specifically comprises the following steps:

step 31, pressing the sleeve (14) into the foundation through the pile driver;

4. The construction method of the deep and soft soil layer of the highway according to claim 3, which is characterized in that: after step 5 is completed, the method further comprises the following steps: and 6, excavating the soil layer on the upper surface of the roadbed (17), filling the soil layer with a mixture of slaked lime and fly ash, and compacting the filled mixture of slaked lime and fly ash by using a construction machine.

5. The construction method of the deep and soft soil layer of the highway according to claim 4, which is characterized in that: a plurality of stirring pieces (7) are arranged on the outer wall of the bottom end of the drainage pipe (5) along the circumferential direction, and the stirring pieces (7) and the drainage grooves (6) are arranged at staggered intervals.

6. The construction method of the deep and soft soil layer of the highway according to claim 5, which is characterized in that: the top fixedly connected with adapter sleeve (8) of drain pipe (5), the cover is equipped with hoisting ring (11) on adapter sleeve (8), hoisting ring (11) are rotated with adapter sleeve (8) along circumference and are connected, be provided with lug (12) on hoisting ring (11).