CN114875732A - Embankment settlement prevention structure and method for expressway reconstruction and extension project - Google Patents

Abstract

The invention discloses a structure and a method for preventing and treating embankment settlement in a highway reconstruction and extension project, wherein the structure comprises a plurality of grouting lifting structures which are buried on steps arranged at the joints of new and old roadbeds; each grouting lifting structure comprises a grouting system and a plurality of lifting systems; the grouting system comprises a grouting outer pipe; the movable grouting device comprises a grouting inner pipe, a grouting chamber and a slurry suction pipe; a plurality of grouting side pipes; the lifting system comprises a lifting pipe, is positioned inside the old roadbed and is vertical to the grouting outer pipe; and the waterproof geotextile bag is positioned inside the new roadbed and is vertical to the grouting outer pipe. According to the embankment settlement prevention structure and the prevention method thereof for the highway reconstruction and extension project, the grouting system and the lifting system are pre-embedded at the reconstruction and extension roadbed, so that soil bodies on two sides of the lifting system are lifted, and the grouting chamber can move in the grouting outer pipe by matching with the grouting inner pipe and the pulley, so that multi-position grouting construction can be realized.

Description

Embankment settlement prevention structure and method for expressway reconstruction and extension project

Technical Field

The invention belongs to the technical field of old road reconstruction and extension projects, and relates to an embankment settlement prevention structure and an embankment settlement prevention method for an expressway reconstruction and extension project.

Background

With the continuous development of the traffic industry in China, the roads designed and constructed in the early stage cannot meet the increasing traffic volume, and the reconstruction, expansion and upgrading of the original roadbed is urgently needed. Because original subgrade settlement has basically been accomplished, there are inhomogeneous combination and inhomogeneous settlement between new and old subgrades for the density nature of subgrade concatenation department is poor, the construction degree of difficulty is big, the density is poor, the problem of the easy inhomogeneous settlement that produces of pavement concatenation department under the vehicle load effect has reduced the feel of going on road surface.

The main solving measures for solving the problem of uneven settlement generated at the position of a reconstructed and expanded roadbed at present are as follows: connecting steel bars, assembled pile foundations, reinforcing plates, geogrids, screws and the like are added at the joints of the old and new roadbeds, so that the connecting strength of the old and new roadbeds is improved, and the uneven settlement of the road surface is reduced. In the engineering, the method of separately filling the inner roadbed and the outer roadbed, expanding the roadbed by using the red mud-based light filler and the like is adopted, so that the connection between the roadbeds is enhanced, and the joint of the new road surface and the old road surface is firmer and more durable. In addition, the pavement settlement is repaired by grouting, so that the cost is low, the effect is good, and the application is wide in recent years. The methods can achieve the purposes of reducing the uneven settlement of the splicing positions of the new and old road surfaces and improving the service performance of the road surfaces, but still have the following defects: (1) the construction difficulty of structures such as connecting steel bars, assembled pile foundations, reinforcing plates and the like is high, and the generated settlement cannot be treated; (2) the road surface settlement is repaired by grouting the embedded grouting pipes, positioning grouting is difficult to realize, the grouting pipes are easy to block by single grouting, and multiple grouting construction cannot be performed.

Disclosure of Invention

In order to achieve the purpose, the invention provides a structure for preventing and treating embankment settlement in a highway reconstruction and extension project and a method for preventing and treating the same. The problem of when present road bed soil slip casting lifting construction, can't carry out location slip casting and slip casting pipe can be blockked up in the slip casting pipe by single slip casting, can't carry out multiposition slip casting is solved.

The technical scheme adopted by the invention is that the embankment settlement prevention structure for the expressway reconstruction and expansion project comprises a plurality of sets of grouting lifting structures which are buried on steps arranged at the joints of new and old roadbeds one by one;

each grouting lifting structure comprises

The grouting system is arranged along the running direction of the road vehicle,

a plurality of lift systems; arranged along the width direction of the road;

wherein the grouting system comprises

The grouting outer pipe is arranged along the driving direction of the road vehicle in the axial direction;

moving the grouting device, and pushing the grouting side pipe into the grouting outer pipe;

the plurality of grouting side pipes are arranged on the grouting outer pipe one by one;

the lifting system comprises

The lifting pipe is positioned inside the old roadbed and is vertically connected with the grouting outer pipe;

and the waterproof geotextile bag is positioned inside the new roadbed and is vertically connected with the grouting outer pipe.

Furthermore, the waterproof geotextile bag of each grouting lifting structure is positioned right above the lifting pipe of the lower grouting lifting structure.

Further, the movable grouting device comprises a grouting inner pipe, a grouting chamber and a slurry suction pipe;

the grouting chamber comprises a grouting inner chamber, one side of the grouting inner chamber is fixedly connected with a first positioning ring, and the other side of the grouting inner chamber is fixedly connected with a second positioning ring; one side of the first positioning ring, which is far away from the grouting inner chamber, is fixedly connected with a fixing ring; one side of the second positioning ring, which is far away from the grouting inner chamber, is fixedly connected with a circular base; wherein the content of the first and second substances,

four positioning clamping grooves are uniformly distributed in the radial direction of the first positioning ring; a first supporting rod is arranged in each positioning clamping groove; one end of each first supporting rod, which is close to the grouting outer pipe, is fixedly provided with a first minor arc arched plate; the four first minor arc cambered plates form a first telescopic ring; one end of each first minor arc-shaped plate, which is close to the grouting outer pipe, is provided with a first rubber film; two ends of each first rubber membrane are respectively fixedly connected with the fixing ring and the grouting inner chamber;

four positioning clamping grooves are uniformly distributed in the radial direction of the second positioning ring; a second supporting rod is arranged in each positioning clamping groove on the second positioning ring; one end of each second support rod, which is close to the grouting outer pipe, is fixedly provided with a second minor arc cambered plate; the four second minor arc cambered plates form a second telescopic ring; one end of each second minor arc-shaped plate close to the grouting outer pipe is provided with a second rubber film; two ends of each second rubber film are respectively fixedly connected with the grouting inner chamber and the round base;

among the four first minor arc arched plates of the first telescopic ring, the radian of two oppositely arranged first minor arc arched plates is larger than that of the other two oppositely arranged first minor arc arched plates, and sliding grooves are formed in the thickness direction of the two oppositely arranged first minor arc arched plates with large radians;

among the four second minor arc arched plates of the second telescopic ring, the radian of two oppositely arranged second minor arc arched plates is larger than that of the other two oppositely arranged second minor arc arched plates, and the thickness directions of the two oppositely arranged second minor arc arched plates with large radians are both provided with sliding grooves;

the first supporting rod and the second supporting rod which are symmetrically arranged in the opposite grouting inner chamber are fixedly connected with two ends of the same rectangular connecting sheet, and four rectangular connecting sheets are arranged together and form a cuboid cavity structure with openings at two sides.

Furthermore, the grouting inner chamber is of a cylindrical cavity structure, and the circular bottom surfaces at two sides are respectively provided with a square opening; four rows of slurry outlet holes are uniformly arranged on the cylindrical surface of the grouting inner chamber.

Furthermore, each grouting side pipe is arranged on one side of the new roadbed; the included angle between each grouting side pipe and the grouting outer pipe is 45 degrees; a grout outlet is formed in the radial 90-degree or 270-degree position of the wall of the grouting outer pipe at intervals along the axial direction of the grouting outer pipe; two adjacent grout outlets are arranged in a staggered mode at the radial 90-degree and 270-degree positions of the tube wall of the grouting outer tube.

Furthermore, the outer side of each slurry outlet is provided with a square blocking piece structure consisting of four triangular blocking pieces, the long edge of each triangular blocking piece is hinged to the outer surface of the grouting outer pipe, each triangular blocking piece is unfolded towards the direction far away from the grouting outer pipe, and the unfolding angle is 80 degrees.

Furthermore, the fixing ring is uniformly provided with four first pulleys in the radial direction; the circular base is evenly provided with four second pulleys in the radial direction.

Furthermore, the square opening of the fixing ring is hinged with the four rectangular connecting pieces through the four trapezoidal connecting pieces.

Furthermore, the outer end of the grouting inner pipe is connected with a grouting machine, and the inner end of the grouting inner pipe is fixedly connected with the square opening of the fixing ring; one end of the grouting chamber is fixedly connected with the grouting inner pipe; the slurry suction pipe is positioned below the grouting inner pipe, and the outer end of the slurry suction pipe is connected with a slurry pumping machine.

Another object of the present invention is to provide a method for preventing and controlling embankment settlement in highway reconstruction and extension projects, including the following steps:

s1: determining a construction position: positioning and measuring the settlement position of the embankment in the reconstruction and extension project, determining the corresponding grouting lifting structure range, extending a grouting chamber into a grouting outer pipe from a grouting side pipe, and pushing the grouting outer pipe to a specified grouting position through a grouting inner pipe;

s2: and (3) starting grouting: firstly, injecting grout into a cuboid cavity formed by four rectangular connecting pieces in a grouting chamber through a grouting inner pipe by adopting the grouting pressure of 100-200 kPa, gradually increasing the grouting pressure to 1-2 MPa, enabling each rectangular connecting piece to push a first supporting rod and a second supporting rod on the rectangular connecting piece, expanding a first telescopic ring and a second telescopic ring to the inner wall of a grouting outer pipe, enabling the grout to flow out of a grout outlet on a grouting inner chamber, and enabling the grout to enter a lifting pipe or a waterproof geotextile bag through a grout outlet; stopping grouting after the pavement recovers to the designed elevation;

s3: stopping grouting: after stopping grouting, the residual grout between the grouting chamber and the grouting outer pipe is sucked out by using a grout sucking pipe, and then the grouting chamber is moved to the next settlement position.

The invention has the beneficial effects that:

(1) according to the embodiment of the invention, the grouting system and the lifting system are pre-buried at the reconstructed and expanded roadbed, a plurality of grout outlet holes are formed in two sides of a lifting pipe in the lifting system, one side of the opening of the periphery of the waterproof geotextile bag is closed and is connected with the grout outlet on the grouting outer pipe, grout can enter soil bodies on two sides of the lifting pipe through the grout outlet holes to lift the soil bodies on two sides of the lifting pipe, and the settlement of the upper part of the lifting pipe can be realized by grouting the waterproof geotextile bag in the grouting lifting structure of the previous stage, so that the lifting of the upper soil body is realized, and the problem that the existing reconstructed and expanded roadbed structure cannot treat the settled roadbed soil is solved.

(2) The telescopic ring in the embodiment of the invention can plug the gap between the left end and the right end of the grouting inner chamber and the grouting outer pipe under the pressure of the grout, so that the grout can only enter the lifting system from the grout outlet on the grouting outer pipe, the grouting efficiency is improved, and the positioning grouting is realized. After grouting stops, the triangular retaining pieces on the grouting outer pipe can prevent backflow of external grout, in addition, the telescopic rings can retract under the action of the rubber films, the grout sucking pipes can suck out redundant grout between the grouting inner chamber and the grouting outer pipe, the grouting inner pipe and the pulleys are matched, the grouting chamber can move in the grouting outer pipe, and multi-position grouting construction can be realized. The problem of during the foundation soil slip casting lifting construction at present, can't carry out location slip casting and slip casting pipe can be blockked up in the slip casting pipe single slip casting, can't carry out multiposition slip casting is solved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic view of an embankment settlement prevention structure in a highway reconstruction and extension project according to an embodiment of the present invention.

Fig. 2 is a floor plan view of a grouting system and a lifting system according to an embodiment of the present invention.

FIG. 3 is a schematic structural diagram of a grouting chamber according to an embodiment of the invention.

Fig. 4 is a cross-sectional view taken at I in fig. 3.

Fig. 5 is a cross-sectional view taken at ii in fig. 3.

Fig. 6 is a schematic diagram of the distribution of slurry outlet holes in the grouting inner chamber according to the embodiment of the invention.

FIG. 7 is a schematic view of a retaining ring according to an embodiment of the present invention.

Fig. 8 is a structural schematic view of a section iii of a grouting outer pipe according to an embodiment of the invention.

Fig. 9 is a side view of fig. 8.

Fig. 10 is a structural schematic diagram of a section iv of a grouting outer pipe according to an embodiment of the invention.

Figure 11 is a side view of a section iv of a slip casting outer tube according to an embodiment of the present invention.

In the figure: 1. the grouting device comprises a grouting system, 2, a lifting system, 3, an outer grouting pipe, 4, a grout outlet, 5, a triangular baffle, 6, an inner grouting pipe, 7, a grouting chamber, 8, a grout suction pipe, 9, a fixing ring, 10, an inner grouting chamber, 11, a grout outlet, 12, a circular base, 13, a first positioning ring, 14, a second positioning ring, 15, a positioning clamping groove, 16, a first pulley, 17, a second pulley, 18, a first supporting rod, 19, a second supporting rod, 20, a first telescopic ring, 21, a second telescopic ring, 22, a first rubber film, 23, a second rubber film, 24, a movable hinge, 25, a trapezoidal connecting sheet, 26, a rectangular connecting sheet, 27, a lifting pipe, 28, a lifting hole, 29, a waterproof geotextile bag, 30, a grouting side pipe, 31, a first minor arc plate, 32, a second minor arc plate and 33, and a chute.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

A structure for preventing and controlling embankment settlement in a highway reconstruction and extension project comprises a plurality of grouting lifting structures which are buried on steps arranged at the joints of new and old roadbeds one by one as shown in figure 1; each grouting lifting structure is staggered with the previous grouting lifting structure (the waterproof geotextile bag 29 of each grouting lifting structure is positioned right above the lifting pipe 27 of the lower grouting lifting structure); each grouting lifting structure comprises a grouting system 1 and a plurality of lifting systems 2; the grouting system 1 is arranged along the running direction of the road vehicle and used for providing slurry required for lifting for the lifting system 2, and the lifting system 2 is arranged along the width direction of the road.

As shown in fig. 2 and 3, the grouting system 1 in each grouting lifting structure is composed of an outer grouting pipe 3, a movable grouting device and a plurality of lateral grouting pipes 30. The axial direction of the grouting outer pipe 3 is arranged along the running direction of the road vehicle; in the horizontal plane of the grouting outer pipe 3, a grouting side pipe 30 is communicated with the grouting outer pipe 3 at intervals of 50m in the axial direction, and the grouting side pipe 30 is used for pushing the movable grouting device into the grouting outer pipe 3; the outer diameter of the grouting side pipe 30 is 10cm, and the inner diameter is 9.5 cm; each grouting side pipe 30 is arranged on one side of the new roadbed; the included angle between each grouting side pipe 30 and the grouting outer pipe 3 is 45 degrees; a grout outlet 4 is arranged at the radial 90-degree or 270-degree position of the pipe wall of the outer grouting pipe 3 every 1.5m along the axial direction of the outer grouting pipe 3; two adjacent slurry outlets 4 are arranged in a staggered manner at the radial positions of 90 degrees and 270 degrees of the pipe wall of the outer grouting pipe 3.

As shown in fig. 8 to 11, a square blocking piece structure composed of four triangular blocking pieces 5 is arranged outside each slurry outlet 4 of the outer grouting pipe 3, the long edge of each triangular blocking piece 5 is hinged to the outer surface of the outer grouting pipe 3, each triangular blocking piece 5 is unfolded towards the direction far away from the outer grouting pipe 3, the unfolding angle is 80 degrees, and the long edge length of each triangular blocking piece 5 is equal to the edge length of the slurry outlet 4.

The movable grouting device consists of a grouting inner pipe 6, a grouting chamber 7 and a slurry suction pipe 8; the outer end of the grouting inner pipe 6 is connected with a grouting machine, and the inner end of the grouting inner pipe is fixedly connected with the grouting chamber 7 (specifically, the grouting inner pipe is fixedly connected with a square opening of the fixing ring 9, and the inner end of the grouting inner pipe 6 can be connected into the square opening of the fixing ring 9 by a screw thread in a solid connection means); one end of the grouting chamber 7 is connected with the grouting inner pipe 6, and the other end is not connected and is a movable end (the other end is specifically a circular base 12); the slurry suction pipe 8 is positioned below the grouting inner pipe 6, the outer end of the slurry suction pipe 8 is connected with a slurry pumping machine, and the inner end of the slurry suction pipe is not connected.

Wherein the grouting outer pipe 3 is a PVC pipe, the outer diameter is 11cm, and the inner diameter is 10 cm; calculating the distance between the pulp outlets 4 according to the distance between the central axes of the pulp outlets 4; the diameter of each slurry outlet 4 is 1 cm-2 cm; the grouting inner pipe 6 is a stainless steel hose, the outer diameter is 5cm, and the inner diameter is 4.5 cm; the slurry suction pipe 8 is a stainless steel hose, and has an outer diameter of 2cm and an inner diameter of 1.8 cm.

As shown in fig. 3 to 7, the grouting chamber 7 is composed of a fixing ring 9, a grouting inner chamber 10, a circular base 12, a first positioning ring 13, a second positioning ring 14, a first pulley 16, a second pulley 17, a first support rod 18, a second support rod 19, a first telescopic ring 20, a second telescopic ring 21, a first rubber film 22, a second rubber film 23, a movable hinge 24, a trapezoidal connecting sheet 25, and a rectangular connecting sheet 26.

The grouting inner chamber 10 is of a cylindrical cavity structure, the axial length is 10 cm-15 cm, the radial diameter is 8cm, square openings (the side length of each square opening is 3.5 cm) are respectively arranged on the circular bottom surfaces on the two sides, a row of slurry outlet holes 11 are respectively arranged on the cylindrical surface of the grouting inner chamber 10 in the directions of 45 degrees, 135 degrees, 225 degrees and 315 degrees, the diameter of each slurry outlet hole 11 is 1cm, and the distance between every two adjacent slurry outlet holes 11 in the same slurry outlet hole 11 is 2 cm.

A first positioning ring 13 (preferably welded) is fixedly connected to one side of the grouting inner chamber 10, and a second positioning ring 14 (preferably welded) is fixedly connected to the other side of the grouting inner chamber; the first positioning ring 13 and the second positioning ring 14 are the same annular devices, the outer diameters of the first positioning ring 13 and the second positioning ring 14 are 6cm, and the circular openings (the diameter of the circular opening is 3.5 cm) inside the first positioning ring 13 and the second positioning ring 14 are respectively and coaxially arranged with the square openings on the two sides of the grouting inner chamber 10; a fixing ring 9 is fixedly connected to one side, away from the grouting inner chamber 10, of the first positioning ring 13 (preferably, a welding mode is adopted), and an inner opening of the fixing ring 9 is square (the side length of the square is 3 cm); a circular base 12 (preferably welded) is fixedly connected to the side of the second positioning ring 14 away from the inner grouting chamber 10, and the circular base 12 is a cylindrical solid structure.

The first positioning ring 13 and the second positioning ring 14 are respectively provided with four positioning clamping grooves 15 which are uniformly distributed in the respective radial direction; the four positioning clamping grooves 15 are respectively arranged at the positions of 0 degree, 90 degrees, 180 degrees and 270 degrees in the radial direction of the first positioning ring 13 or the second positioning ring 14; each positioning clamping groove 15 is of a rectangular structure; a first supporting rod 18 is respectively arranged in each positioning clamping groove 15 on the first positioning ring 13; a second support rod 19 is respectively arranged in each positioning clamping groove 15 on the second positioning ring 14; one end of each first support rod 18 close to the grouting outer pipe 3 is fixedly provided with a first minor arc arched plate 31; the four first minor arc arcuate plates 31 constitute the first telescopic ring 20; one end of each second support rod 19 close to the grouting outer pipe 3 is fixedly provided with a second minor arc cambered plate 32; four second minor arc-shaped plates 32 form a second telescopic ring 21; the first minor arc cambered plate 31 and the second minor arc cambered plate 32 are both made of stainless steel; one end of each first minor arc-shaped plate 31 close to the grouting outer pipe 3 is provided with a first rubber film 22, and one end of each second minor arc-shaped plate 32 close to the grouting outer pipe 3 is provided with a second rubber film 23; two ends of each first rubber film 22 are respectively fixedly connected with the fixing ring 9 and the grouting inner chamber 10; two ends of each second rubber film 23 are fixedly connected with the grouting inner chamber 10 and the circular base 12 respectively; the elastic modulus of each of the first rubber film 22 and the second rubber film 23 is 20 kPa.

Among the four first minor arc arcuate plates 31 of the first telescopic ring 20, the radian of two first minor arc arcuate plates 31 which are oppositely arranged is 38.2 degrees, and the thickness directions of the two first minor arc arcuate plates 31 are both provided with sliding grooves 33; the radian of the other two oppositely arranged first minor arc cambered plates 31 is 28.7 degrees, and the two first minor arc cambered plates 31 with the radian of 28.7 degrees can slide in the sliding grooves 33 of the two first minor arc cambered plates 31 with the radian of 38.2 degrees; when the four first minor arc arcuate plates 31 are expanded to the outermost side, the two first minor arc arcuate plates 31 having the curvature of 28.7 ° are positioned inside the two first minor arc arcuate plates 31 having the curvature of 38.2 °, and the first minor arc arcuate plates 31 do not interfere with each other, and the contraction process of the first telescopic ring 20 is not prevented.

The arrangement of the four second minor arc arcuate plates 32 of the second shrink ring is the same as the arrangement of the four minor arc arcuate plates 20 of the first shrink ring.

The first support rod 18 and the second support rod 19 which are symmetrically arranged relative to the grouting inner chamber 10 are fixedly connected with two ends of the same rectangular connecting piece 26, four rectangular connecting pieces 26 are arranged, the four rectangular connecting pieces 26 form a cuboid cavity structure with openings at two sides, and the length of the short side of each rectangular connecting piece 26 is 2 cm.

The fixed ring 9 is uniformly provided with four first pulleys 16 in the radial direction; the four first pulleys 16 are respectively arranged at the positions of 0 degrees, 90 degrees, 180 degrees and 270 degrees on the radial direction of the fixing ring 9; the circular base 12 is uniformly provided with four second pulleys 17 in the radial direction; the four second pulleys 17 are respectively arranged at the positions of 0 degrees, 90 degrees, 180 degrees and 270 degrees in the radial direction of the circular base 12.

The square opening of the fixed ring 9 is hinged with four rectangular connecting sheets 26 through four trapezoidal connecting sheets 25; each trapezoidal connecting piece 25 is made of rubber material; the long edge of each trapezoidal connecting piece 25 is hinged to one side of the square opening of the fixing ring 9 through a movable hinge 24; the short side of each trapezoidal link 25 is hinged by a living hinge 24 to a rectangular link 26.

The inner diameter of the square opening of the fixing ring 9 is smaller than the outer diameter of the grouting inner pipe 6, so that the grouting inner pipe 6 is connected with the grouting chamber 7 by being clamped in the square opening of the fixing ring 9.

When grouting starts, grout is injected through the grouting inner pipe 6 and enters a square opening of the fixing ring 9 on the grouting chamber 7, the grout fills a cuboid cavity formed by four rectangular connecting pieces 26 under the condition of low pressure, then the pressure in the cuboid cavity is gradually increased, the four rectangular connecting pieces 26 can expand towards the direction close to the grouting outer pipe 3 under the pressure of the grout, each rectangular connecting piece 26 pushes the first supporting rod 18 and the second supporting rod 19 fixedly connected with the rectangular connecting piece to move towards the direction close to the grouting outer pipe 3 under the action of the hydraulic pressure of the grout, the corresponding first inferior arc cambered plate 31 and the second inferior arc cambered plate 32 expand towards the direction close to the grouting outer pipe 3, and the first telescopic ring 20 and the second telescopic ring 21 respectively block off spaces between the left side and the right side of the grouting inner chamber 10 and the grouting outer pipe 3; at this time, a gap is formed between adjacent rectangular connecting sheets 26, and the gap is increased along with the increase of slurry pressure, so that slurry overflows from a slurry outlet hole 11 in the grouting inner chamber 10, and slurry cannot flow out to the left and right sides of the grouting inner chamber 10 and can only flow out from a slurry outlet 4 in the grouting outer pipe 3 (by planning a grouting lifting structure, the grouting chamber 7 is pushed into the slurry outlet 4 needing to be lifted from the grouting side pipe 30 to the grouting outer pipe 3 through the grouting inner pipe 6), the slurry pressure is 0 after grouting is stopped, the first telescopic ring 20 and the second telescopic ring 21 retract under the tension of the first rubber film 22 and the second rubber film 23, and the residual slurry between the grouting inner chamber 10 and the grouting outer pipe 3 can be sucked out through a slurry suction pipe 8 below the grouting inner pipe 6. The grouting chamber 7 can move in the outer grouting pipe 3 and the side grouting pipe 30 under the traction of the inner grouting pipe 6.

After grouting is stopped, the pressure of the grout outside the grout outlet 4 is greater than that of the grout inside the grout outlet 4, if the triangular baffle 5 is not arranged, grout recharging can occur, and due to the triangular baffle 5, the grout outside the grout outlet 4 acts on the back of the triangular baffle 5, so that the triangular baffle 5 is closed, and the grout is prevented from recharging.

Each lifting system 2 consists of a lifting tube 27 and a waterproof geotextile bag 29. In the horizontal plane of the grouting outer pipe 3, each lifting system 2 is perpendicular to the grouting outer pipe 3, a lifting pipe 27 and a waterproof geotextile bag 29 are respectively connected with two adjacent grout outlets 4 on the grouting outer pipe 3, the lifting pipe 27 is positioned inside an old roadbed, and the waterproof geotextile bag 29 is positioned inside a new roadbed.

Each lifting pipe 27 is connected with the grout outlet 4 positioned at 270 degrees on the grouting outer pipe 3, and one end far away from the grout outlet 4 is plugged; the outer diameter of each lifting pipe 27 is 1.5-2.5 cm, and the inner diameter is 1-2 cm. Each lifting pipe 27 is provided with lifting holes 28 with the diameter of 1cm along the axial direction at intervals of 10cm, and every two adjacent lifting holes 28 are arranged at the positions of 90 degrees and 270 degrees in the radial direction of the lifting pipe 27 in a staggered mode. Grout enters the lifting pipe 27 from the grout outlet 4, is horizontally injected into the old roadbed soil body from the lifting hole 28, the grout layer is added into the soil layer, and after the grout layer is solidified, the old roadbed soil bodies on the two sides of the lifting pipe 27 are lifted.

The waterproof geotextile bag 29 is a sealed bag, the width of the waterproof geotextile bag is 20cm, the length of the waterproof geotextile bag is 40cm, and one side opening of the waterproof geotextile bag is connected with the grout outlet 4 at the position of 90 degrees on the grouting outer pipe 3. The slurry enters the waterproof geotextile bag 29 from the slurry outlet 4, and after the slurry is solidified, the new roadbed soil body on the upper part of the waterproof geotextile bag 29 can be vertically lifted.

The embodiment provides a construction method for an embankment settlement prevention structure of a highway reconstruction and extension project, which comprises the following specific steps:

step 1: excavating a slope surface: and arranging slopes step by step on the side to be widened of the old roadbed slope with the slope of 1 degree, so that the roadbed interface at the position to be widened is in a step shape, and the height and the width of each step are 25cm and 25cm respectively.

Step 2: layered filling: the new roadbed adopts a layered filling and compacting method, and the filling thickness of each layer is consistent with the height of each layer of step.

And step 3: pre-buried slip casting lifting structure: after a first layer of roadbed is filled, a first set of grouting lifting structure is arranged, an outer grouting pipe 3 and a lateral grouting pipe 30 are arranged on a first step, a lifting pipe 27 is inserted into an old roadbed, a waterproof geotextile bag 29 is laid on the newly filled roadbed, then a second layer of filling is carried out, a second set of grouting lifting structure is continuously arranged at a third step, the latter set of grouting lifting structure and the former set of grouting lifting structure are arranged in a staggered manner, and the waterproof geotextile bag 29 of each set of grouting lifting structure is positioned right above the lifting pipe 27 of the former set of grouting lifting structure; every other step is provided with a set of grouting lifting structure.

When the road surface is reconstructed and expanded to generate settlement, the technical scheme adopted by the embodiment of the invention is that the embankment settlement prevention and control scheme of the highway reconstruction and expansion project is carried out according to the following steps:

s1: determining a construction position: and (3) positioning and measuring the settlement position of the embankment in the reconstruction and extension project by adopting a level gauge, determining the corresponding grouting lifting structural range, extending the grouting chamber 7 into the grouting outer pipe 3 from the grouting side pipe 30, and pushing the grouting chamber to the specified grouting position through the grouting inner pipe 6.

S2: and (3) starting grouting: firstly, cement grout is injected into a cuboid cavity formed by four rectangular connecting pieces 26 in a grouting chamber 7 through a grouting inner pipe 6 by adopting the grouting pressure of 100-200 kPa, then the grouting pressure is gradually increased to 1-2 MPa, each rectangular connecting piece 26 pushes a first supporting rod 18 and a second supporting rod 19 on the rectangular connecting piece, a first telescopic ring 20 and a second telescopic ring 21 are expanded to the inner wall of a grouting outer pipe 3, the cement grout flows out from a grout outlet 11 on a grouting inner chamber 10, and after entering the cavity between the grouting inner chamber 10 and the grouting outer pipe 3, the cement grout cannot flow left and right under the limitation of the first telescopic ring 20 and the second telescopic ring 21 and can only enter a lifting pipe 27 or a waterproof geotextile bag 29 from a grout outlet 4 on the grouting outer pipe 3;

when cement grout enters the lifting pipe 27, the cement grout is horizontally injected into the old roadbed soil body through the lifting hole 28 on the lifting pipe 27 to split the soil body, and a grout layer is added into the soil layer to lift the old roadbed soil bodies on two sides of the lifting pipe 27.

When cement slurry enters the waterproof geotextile bags 29, the waterproof geotextile bags 29 are expanded, and new roadbed soil on the upper parts of the waterproof geotextile bags 29 is vertically lifted;

the lifting of the soil body on the upper part of the lifting pipe 27 of each grouting lifting structure is completed by the waterproof geotextile bag 29 of the previous grouting lifting structure;

and stopping grouting after the pavement is recovered to the designed elevation.

S3: stopping grouting: after grouting is stopped, the grouting pressure is changed to 0, the first telescopic ring 20 and the second telescopic ring 21 are gradually retracted under the tension of the first rubber film 22 and the second rubber film 23, redundant grout between the grouting chamber 7 and the grouting outer pipe 3 is sucked out by using the grout sucking pipe 8, then the grouting chamber 7 is moved to the next subsidence, and the steps S1, S2 and S3 are repeated.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims (10)

1. A levee settlement prevention structure for highway reconstruction and expansion projects is characterized by comprising a plurality of grouting lifting structures which are buried on steps arranged at the joints of new and old roadbeds one by one;

each grouting lifting structure comprises

A grouting system (1) arranged along the driving direction of the road vehicle,

a plurality of lifting systems (2); arranged along the width direction of the road;

wherein the grouting system (1) comprises

A grouting outer tube (3) whose axial direction is arranged along the road vehicle traveling direction;

moving the grouting device, and pushing the grouting device into the grouting outer pipe (3) from the grouting side pipe (30);

the plurality of grouting side pipes (30) are arranged on the grouting outer pipe (3) one by one;

the lifting system (2) comprises

The lifting pipe (27) is positioned inside the old roadbed and is vertically connected with the grouting outer pipe (3);

and the waterproof geotextile bag (29) is positioned inside the new roadbed and is vertically connected with the grouting outer pipe (3).

2. The embankment settlement prevention structure for highway rebuilding and expanding project according to claim 1, wherein the waterproof geotextile bags (29) of each set of grouting lifting structures are located right above the lifting pipes (27) of the lower grouting lifting structures.

3. The embankment settlement prevention structure for highway rebuilding and expanding engineering according to claim 1, wherein the mobile grouting device comprises a grouting inner pipe (6), a grouting chamber (7) and a slurry suction pipe (8);

the grouting chamber (7) comprises a grouting inner chamber (10), one side of the grouting inner chamber (10) is fixedly connected with a first positioning ring (13), and the other side of the grouting inner chamber is fixedly connected with a second positioning ring (14); one side of the first positioning ring (13) far away from the grouting inner chamber (10) is fixedly connected with a fixing ring (9); a circular base (12) is fixedly connected to one side, away from the grouting inner chamber (10), of the second positioning ring (14); wherein the content of the first and second substances,

four positioning clamping grooves (15) are uniformly distributed in the radial direction of the first positioning ring (13); a first supporting rod (18) is arranged in each positioning clamping groove (15); one end of each first support rod (18) close to the grouting outer pipe (3) is fixedly provided with a first minor arc cambered plate (31); the four first minor arc-shaped plates (31) form a first telescopic ring (20); one end of each first minor arc-shaped plate (31) close to the grouting outer pipe (3) is provided with a first rubber film (22); two ends of each first rubber film (22) are respectively and fixedly connected with the fixing ring (9) and the grouting inner chamber (10);

four positioning clamping grooves (15) are uniformly distributed in the radial direction of the second positioning ring (14); a second support rod (19) is arranged in each positioning clamping groove (15) on the second positioning ring (14); one end of each second support rod (19) close to the grouting outer pipe (3) is fixedly provided with a second minor arc cambered plate (32); the four second minor arc-shaped plates (32) form a second telescopic ring (21); one end of each second minor arc-shaped plate (32) close to the grouting outer pipe (3) is provided with a second rubber film (23); two ends of each second rubber film (23) are respectively fixedly connected with the grouting inner chamber (10) and the circular base (12);

among four first minor arc cambered plates (31) of the first telescopic ring (20), the radian of two oppositely arranged first minor arc cambered plates (31) is greater than that of the other two oppositely arranged first minor arc cambered plates (31), and sliding grooves (33) are formed in the thickness direction of the two oppositely arranged first minor arc cambered plates (31) with large radians;

among four second minor arc cambered plates (32) of the second telescopic ring (21), the radian of two oppositely arranged second minor arc cambered plates (32) is greater than that of the other two oppositely arranged second minor arc cambered plates (32), and sliding grooves (33) are formed in the thickness direction of the two oppositely arranged second minor arc cambered plates (32) with large radians;

the first supporting rod (18) and the second supporting rod (19) which are symmetrically arranged relative to the grouting inner chamber (10) are fixedly connected with two ends of the same rectangular connecting piece (26), four rectangular connecting pieces (26) are arranged, and the four rectangular connecting pieces (26) form a cuboid cavity structure with openings at two sides.

4. The embankment settlement prevention structure for the highway reconstruction and expansion project according to claim 3, wherein the grouting inner chamber (10) is a cylindrical cavity structure, and a square opening is respectively arranged on the circular bottom surfaces at two sides; four rows of slurry outlet holes (11) are uniformly formed in the cylindrical surface of the grouting inner chamber (10).

5. The embankment settlement prevention structure for expressway reconstruction and expansion projects according to claim 1, wherein each grouting side pipe (30) is arranged on one side of a new roadbed; the included angle between each grouting side pipe (30) and the grouting outer pipe (3) is 45 degrees; a slurry outlet (4) is formed in the radial 90-degree or 270-degree position of the pipe wall of the outer grouting pipe (3) at intervals along the axial direction of the outer grouting pipe (3); two adjacent slurry outlets (4) are arranged at the radial 90-270 degrees of the tube wall of the outer grouting tube (3) in a staggered manner.

6. The embankment settlement prevention structure for highway reconstruction and expansion engineering according to claim 5, wherein a square blocking piece structure consisting of four triangular blocking pieces (5) is arranged on the outer side of each grout outlet (4), the long side of each triangular blocking piece (5) is hinged to the outer surface of the grouting outer pipe (3), each triangular blocking piece (5) is unfolded in a direction away from the grouting outer pipe (3), and the unfolding angle is 80 degrees.

7. The embankment settlement prevention structure for highway rebuilding and expanding engineering according to claim 3, wherein the fixing ring (9) is provided with four first pulleys (16) uniformly in radial direction; the circular base (12) is uniformly provided with four second pulleys (17) in the radial direction.

8. The embankment settlement prevention structure for expressway reconstruction and expansion projects according to claim 3, wherein the square opening of the fixing ring (9) is hinged to four rectangular connecting pieces (26) through four trapezoidal connecting pieces (25).

9. The embankment settlement prevention structure for the highway reconstruction and extension project according to claim 1, wherein the outer end of the grouting inner pipe (6) is connected with a grouting machine, and the inner end of the grouting inner pipe is fixedly connected with a square opening of the fixing ring (9); one end of the grouting chamber (7) is fixedly connected with the grouting inner pipe (6); the slurry suction pipe (8) is positioned below the grouting inner pipe (6), and the outer end of the slurry suction pipe is connected with a slurry pumping machine.

10. The method for preventing the embankment settlement prevention structure of the highway reconstruction and extension project according to any one of claims 1 to 9, comprising the following steps of:

s1: determining a construction position: positioning and measuring the settlement position of the embankment in the reconstruction and extension project, determining the corresponding grouting lifting structure range, extending the grouting chamber (7) into the grouting outer pipe (3) from the grouting side pipe (30), and pushing the grouting outer pipe to a specified grouting position through the grouting inner pipe (6);

s2: and (3) starting grouting: firstly, injecting grout into a cuboid cavity formed by four rectangular connecting sheets (26) in a grouting chamber (7) through a grouting inner pipe (6) by adopting a grouting pressure of 100-200 kPa, then gradually increasing the grouting pressure to 1-2 MPa, enabling each rectangular connecting sheet (26) to push a first supporting rod (18) and a second supporting rod (19) on the rectangular connecting sheet, expanding a first telescopic ring (20) and a second telescopic ring (21) to the inner wall of a grouting outer pipe (3), enabling the grout to flow out of a grout outlet (11) on the grouting outer pipe (10), and enabling the grout to enter an inner lifting pipe (27) or a waterproof geotextile bag (29) through a grout outlet (4); stopping grouting after the pavement recovers to the designed elevation;

s3: stopping grouting: and after stopping grouting, sucking out the residual slurry between the grouting chamber (7) and the grouting outer pipe (3) by using the slurry sucking pipe (8), and moving the grouting chamber (7) to the next settlement position.

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