CN114687345A - Method for repairing surface subsidence or deformation of underground pipe outside foundation pit enclosure wall - Google Patents

Abstract

The invention discloses a method for repairing surface settlement or deformation of underground pipes on the outer side of a foundation pit enclosure wall. The settlement value of the surface soil outside the retaining wall of the foundation pit or the deformation settlement value of the underground pipe or the horizontal movement value of the deformation of the underground pipe; according to the height position, lateral position and horizontal or oblique direction to be repaired obtained from the monitoring value, the foundation is determined. The location and direction of the construction holes on the pit retaining wall; use a drilling rig to drill the holes, place grouting pipes, bolts and multiple geotextile bags extending along the axial direction, and grouting so that each geotextile bag is filled with cement slurry and solidified The latter grouting body constitutes a set of slurry pockets to lift the subsidence soil outside the foundation pit or reset the deformed underground pipe. The method does not carry out construction on the surface outside the foundation pit, and the grouting to restore the surface uplift or the reset of the underground pipe has strong pertinence and good recovery or reset effect.

Description

Repair method for surface settlement or deformation of underground pipe on the outer side of retaining wall of foundation pit

technical field

The invention relates to the technical field of foundation reinforcement, in particular to a method for repairing surface settlement or deformation of underground pipes on the outer side of a retaining wall of a foundation pit.

Background technique

During the development and construction of the underground space in the soft soil area, the soil excavation process in the foundation pit will generally cause the foundation pit retaining wall or the foundation pit retaining structure such as the underground diaphragm wall or the outer water-stop curtain and the inner supporting piles. The formed retaining wall is displaced to the inside of the foundation pit, and this displacement will cause the soil outside the foundation pit or the outer side of the foundation pit retaining wall to deform toward the foundation pit retaining wall, resulting in surface settlement or various pre-buried underground of municipal engineering. Tube deformation. In particular, improper excavation of the foundation pit will cause excessive deformation of the retaining wall of the foundation pit. Even cause road cracking and collapse.

The traditional treatment method is to increase the depth of the retaining wall of the foundation pit or increase the stiffness of the support in the foundation pit, or to reinforce the bottom of the retaining wall of the foundation pit, or to adopt the measures of zoning and block excavation during the excavation process of the foundation pit. Advance control of settlement or deformation of underground pipelines. However, the reinforcement and protection of this method are blind, and the investment is often large and the income is small. The cracking and collapse of the road caused by the surface settlement or the deformation of the underground pipe have not been effectively controlled, and the technical problem has not been well solved. resolved.

Later, some technicians used grouting to repair the surface settlement or the deformation of the underground pipe. For example, vertical grouting or oblique grouting was used to repair the surface settlement on the ground outside the foundation pit. After drilling, vertical grouting is used to repair the settlement and deformation of underground pipes. The above grouting repair methods for surface settlement or underground pipe deformation outside the foundation pit in the prior art still have the following shortcomings: due to vertical grouting or oblique grouting from the ground surface, the lifting of the surface is restored or the deformation of the underground pipe is reset. The pertinence is not strong, such as the lifting effect on settlement or collapse is not obvious, the position that needs to be lifted may not be lifted, and the position that does not need lifting may be lifted again. Another example is drilling a hole in an underground pipe, creating a wound for the underground pipe, and the deformation of the underground pipe is complicated, and the deformation is not necessarily directly below the underground pipe. Therefore, the restoration or restoration effect of this grouting method is not obvious, and the proportion of cement grout that does not play the role of restoration or restoration is relatively large, resulting in a large waste of grout and high restoration costs. In addition, since the grouting is operated on the surface to be repaired outside the foundation pit, traffic control is required throughout the construction process, which brings inconvenience to traffic, and the construction space is limited, which may not only hinder normal construction, but also damage the original road surface and surface. facilities, and the construction equipment vibrates on the surface to be repaired or ground, and new surface subsidence or underground pipe deformation may occur.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to provide a surface outside the foundation pit enclosure wall that is not constructed on the ground outside the foundation pit, and that the grouting can lift the ground or restore the underground pipe with strong pertinence and good recovery or reset effect. Repair methods for settlement or deformation of underground pipes.

The technical solution of the present invention is to provide a repair method for the surface settlement or the deformation of the underground pipe on the outer side of the retaining wall of the foundation pit, including the following construction steps:

(1) According to the prediction and evaluation data, one or more rows of steel pipes are pre-buried on the underground continuous wall in the retaining wall of the foundation pit, each row is multiple, and each steel pipe is in a horizontal state or a high foundation inside the foundation pit Low oblique state on the outside of the pit;

(2) Set up multiple monitoring points in the surface subsidence area or the underground pipe control area outside the retaining wall of the foundation pit. The monitoring points are arranged in the radial and latitudinal directions. The monitoring equipment is used to timely obtain the retaining wall of the foundation pit when the foundation pit is excavated. The settlement value of the outer surface soil mass or the deformation settlement value of the underground pipe or the horizontal movement value of the underground pipe deformation;

(3) Determine the position and direction of the construction hole on the retaining wall of the foundation pit according to the height position, lateral position and horizontal or oblique direction to be repaired obtained from the monitoring value: the first construction hole on the underground continuous wall is pre-buried The first construction holes are one or more rows, each row is multiple; the second construction holes of the enclosure wall formed by the outer water-stop curtain and the inner supporting row piles are in the supporting row. The soil of the gap between the supporting piles adjacent to the pile is selected and marked. The second construction holes are in one or more rows, and each row is multiple. The second construction holes are in a horizontal state or in a high foundation pit inside the foundation pit. Outer side low oblique state;

(4) Determine the length of the geotextile bag, the length of the anchor rod set in the geotextile bag and the length of the grouting pipe according to the depth of the hole to be drilled, the height of the soil to be lifted or the distance to be traversed according to the monitoring value. and the diameter of each geotextile bag in the multiple geotextile bags formed by binding, wherein the grouting pipe leaves a length for connecting the grouting pump, and each geotextile bag corresponds to one or more grouting holes;

(5) Use a drilling rig to drill a horizontal hole, place a horizontal grouting pipe, a horizontal bolt and a plurality of geotextile bags extending along the axial direction, grouting so that each geotextile bag is filled with cement slurry and solidified. The grouting body forms a group of horizontal slurry pockets to lift the subsidence soil outside the foundation pit or lift the deformed underground pipe, and the horizontal slurry pockets are arranged in multiple rows, and each row has multiple groups; or

The grouting body is formed by drilling oblique holes with a drilling rig, placing oblique grouting pipes, oblique bolts and multiple geotextile bags extending along the axial direction, and grouting so that each geotextile bag is filled with cement slurry and solidified. A group of oblique pulp sac bags are used to lift the deformed underground pipe on the outside of the foundation pit or horizontally abut the deformed underground pipe, and the oblique pulp sac bags are in multiple rows, and each row is multiple groups;

(6), grouting makes the first construction hole at the outer end of the steel pipe block and solidifies to facilitate the water stop, and cut the grouting pipe in the steel pipe; The second construction hole on the soil body of the gap is blocked and solidified to facilitate water stop, and the grouting pipe extending out of the inner side of the foundation pit of the second construction hole is cut.

After adopting the above construction steps, the method for repairing the surface settlement or the deformation of the underground pipe on the outer side of the retaining wall of the foundation pit of the present invention has the following advantages:

Since there are multiple monitoring points in the surface settlement area or the underground pipe control area outside the foundation pit retaining wall, the monitoring points are arranged in the radial and latitudinal directions, and monitoring equipment is used to timely obtain the surface soil outside the foundation pit retaining wall during the excavation of the foundation pit. Volume settlement value or underground pipe deformation settlement value or underground pipe deformation horizontal movement value. In addition, the position and direction of the construction holes on the retaining wall of the foundation pit are determined according to the height to be repaired, the lateral position and the horizontal or oblique direction obtained according to the monitoring values. 2. The construction holes can be drilled horizontally or obliquely, and the length of the geotextile bag and the anchor rod set in the geotextile bag are determined according to the depth of the drilled hole, the height of the soil to be lifted, or the distance to be moved laterally according to the monitoring value. The length of the grouting pipe and the diameter of each geotextile bag in the plurality of geotextile bags formed by the binding. And the horizontal hole of the soil below the subsidence of the surface or the horizontal hole of the soil below the deformed underground pipe, or the oblique hole of the side soil of the underground pipe or the oblique hole of the soil below the underground pipe Each horizontal grouting pipe or oblique grouting pipe is bound with multiple geotextile bags along the axial direction. After filling with cement slurry and solidification, it constitutes the horizontal grouting of the uplifted soil to restore the subsidence surface or reset the underground deformed pipe. Capsular bag or oblique plasma sac. The lifting recovery of ground subsidence or cracking or the reset of underground pipes is highly targeted, and it can accurately determine where to lift and where the underground pipes need to be moved laterally, and targeted at the subsidence or subsidence soil or under the underground pipe. The horizontal bolt, the horizontal grouting pipe and the horizontal slurry bag or the oblique bolt, the oblique grouting pipe and the oblique slurry bag are arranged at the side and below, and the lifting and reset process of the deformed underground pipe will not affect the deformation of the underground pipe. The underground pipe itself produces wounds, and the underground pipe can be deformed and repaired in two vector directions, vertical and horizontal. The effect of surface subsidence or the uplift and recovery of subsidence soil or the uplift of underground pipe deformation or the reset effect of transverse contact are obvious. And because the slurry bag is lifted at a fixed point, the geotextile bag wraps the slurry, the slurry does not spread, and the grouting quality is guaranteed. By estimating the total volume, not only a good filling effect of grouting can be obtained, that is, lifting and reset effects, but also the consumption of cement slurry is relatively small, which greatly reduces the repair cost.

Due to the use of construction holes to operate on the inside of the excavated foundation pit, drilling and placement of the soil below the subsidence surface outside the foundation pit or the soil below the deformed underground pipe or the soil on the side of the deformed underground pipe Anchor rods, grouting pipes, geotextile bags, grouting and other operations do not need to be operated on the surface to be repaired outside the foundation pit, and no traffic control is required during the construction process. During the construction period, the ground traffic outside the foundation pit can remain normal and unchanged. Unrestricted, it can ensure the normal and smooth progress of the repair construction, and will not damage the original road surface and facilities outside the foundation pit, and because the construction equipment is constructed in the foundation pit, the vibration of the soil outside the foundation pit is relatively small, and it will not be damaged by the repair construction. And new surface subsidence or underground pipe deformation occurs.

Further, in step (1), the inner end of the foundation pit of each steel pipe protrudes from the inner surface of the underground diaphragm wall, and the sealing cover is tightened on the inner end of the foundation pit of the steel pipe before pre-embedding and after the grouting construction is completed; Before burying, the outer end of the foundation pit of each steel pipe shall be sealed with temporary sealing material. After the above construction steps are adopted, according to the construction experience or the results of the monitoring and evaluation of the soil outside the diaphragm wall and the pre-buried underground pipes of the municipal engineering, the pre-buried positions that may need to be lifted and reset can be pre-buried as the first step. 1. Steel pipes for construction holes, both ends of the steel pipes are blocked during pre-embedding to avoid concrete blockage and contamination of the inner holes of the steel pipes during the concrete pouring construction of the underground continuous wall. The construction step can ensure that the first construction hole pre-buried in the underground continuous wall is easy to construct and operate, guarantees the repair effect, and has a firm and reliable structure, and it is convenient to open the first construction hole or block the first construction hole. After the construction is completed, it can be sealed to stop water and ensure the integrity and durability of the repaired structure constructed by this construction method.

Further, in the multiple rows of steel pipes in step (1), the adjacent upper and lower rows of steel pipes are staggered: the adjacent upper and lower rows of steel pipes are not on the same vertical line. After the above construction steps are adopted, not only a good repair effect can be ensured, but also the weakening effect on the rigidity of the underground diaphragm wall which may be caused by opening holes in the underground diaphragm wall can be minimized.

Further, in step (3), each row of construction holes is arranged on the surrounding wall of the foundation pit between the upper and lower sides of the two rows of supporting surrounding beams. After the above construction steps are adopted, it is helpful for the following repair of the surface settlement soil outside the foundation pit or the reset or repair of the deformed underground pipe to effectively fit the excavation engineering construction in the foundation pit.

Further, in step (5), the repair of the surface settlement soil outside the foundation pit or the reset of the deformed underground pipe is coordinated with the excavation project in the foundation pit: the excavation operation in the foundation pit is carried out to the foundation pit surrounding beam below a row of construction holes. After the excavation face of the lower foundation pit, it is necessary to carry out the pouring work of the inner support of the reinforced concrete of the foundation pit. At this time, the excavation operation in the foundation pit is suspended. After the inner support of the reinforced concrete of the foundation pit reaches the predetermined strength, the soil will continue to be excavated downward. The construction of step (5) is carried out at this position and at this time point. After the above construction steps are adopted, the repair of the subsidence soil outside the foundation pit or the reset of the deformed underground pipe can be effectively or very well matched with the excavation work in the foundation pit. After the excavation surface of the foundation pit on the lower part of the pit surrounding beam, it is necessary to carry out the pouring work of the reinforced concrete inner support of the foundation pit. At this time, the excavation operation in the foundation pit is suspended, and the reinforced concrete inner support of the foundation pit reaches the predetermined strength before continuing to dig downward. Soil, at this position and at this time, the repair of the surface settlement soil outside the foundation pit or the restoration of the deformed underground pipe will not affect the construction period of the foundation pit excavation, but also make the grouting repair construction space larger, and the construction The conditions are more ideal, the construction operation is more convenient, and the construction is smoother.

Further, in step (5), a plurality of horizontal grout pockets connected to a horizontal grouting pipe are located in the horizontal hole of the soil below the subsidence of the ground outside the foundation pit or the underground pipe deformed outside the foundation pit. In the horizontal hole of the following soil mass; multiple oblique slurry pockets connected to an oblique grouting pipe are located in the oblique hole of the soil body on the side of the deformed underground pipe outside the foundation pit or the deformed underground pipe outside the foundation pit In the oblique hole of the following soil. After the above construction steps are adopted, the horizontal slurry pockets located at the subsidence of the surface soil mass and the horizontal slurry pockets located at the subsidence of the soil body of the deformed underground pipe have a better effect on the lifting and repair of the settled soil mass or the deformed underground pipe. , more targeted, to achieve the harmony and unity of lifting repair and saving cement slurry materials. The oblique pulp pockets located at the subsidence of the soil body of the deformed underground pipe or the soil on the side of the deformed underground pipe have a better effect on the lifting and repairing of the deformation and settlement part or the transversal translation reset, and are more targeted, so that the lifting and repairing, Harmony and unity of horizontal and translational repair and saving cement slurry materials.

Further, in step (5), the end of the horizontal bolt in the horizontal hole away from the retaining wall of the foundation pit is fixed in the countersunk hole of the adjacent underground continuous wall, and the horizontal grouting pipe also extends to the countersunk hole. The inside can be grouted into the counterbore to fix it. After the above construction steps are adopted, the horizontal grouting pipe with the horizontal slurry bag can be fixed by the two ends of the horizontal bolt to form a stretcher structure and the horizontal slurry bag can be kept in a horizontal state, so as to better realize the The role of lifting and strengthening soil.

Description of drawings

1 is a vertical cross-sectional structural schematic diagram of the repair structure constructed by the repair method of the present invention when it is arranged horizontally (it can be understood that the horizontal grouting pipe is parallel to the horizontal anchor rod and the horizontal anchor rod is blocked).

2 is a schematic view of the vertical arrangement of the first construction hole formed by the pre-embedded steel pipe in an embodiment of the repair structure constructed by the repair method of the present invention on the underground continuous wall viewed from the inside of the foundation pit.

3 is a vertical cross-sectional structural schematic diagram of an embodiment of the pre-embedded steel pipe, the sealing cover at the inner end and the sealing material at the outer end in the repair structure constructed by the repair method of the present invention (it can be understood as the horizontal grouting pipe and the horizontal The anchors are parallel and the horizontal anchors are blocked).

4 is a vertical cross-sectional structural schematic diagram of the repair structure constructed by the repair method of the present invention in a horizontal and oblique cross-arrangement (it can be understood that the horizontal grouting pipe is parallel to the horizontal bolt and the horizontal bolt is blocked. ; the oblique grouting pipe is parallel to the oblique bolt and the oblique bolt is blocked).

5 is a vertical cross-sectional structural schematic diagram of the repair structure constructed by the repair method of the present invention when it is horizontally arranged and connected to the adjacent underground diaphragm wall in two rows (it can be understood as the horizontal grouting pipe and the horizontal bolt Parallel and horizontal bolts are blocked; there may be grouting in the counterbore).

Fig. 6 is a structural schematic diagram of the connection between the anchor rod and the adjacent underground diaphragm wall when one of the repair structures constructed by the repair method of the present invention is arranged horizontally (it can be understood that the horizontal grouting pipe is parallel to the horizontal anchor rod and the horizontal direction Grouting pipe is blocked).

FIG. 7 is a schematic diagram of the use of a drilling rig to drill an oblique hole through a pre-buried steel pipe in the repair method of the present invention.

8 is a schematic top view of the layout of monitoring points for surface settlement or underground pipe deformation outside the foundation pit in the repair method of the present invention (seven horizontal rectangles can be understood as a schematic diagram of a horizontal pulp bag or a schematic diagram of an oblique pulp bag).

As shown in the picture: 1. Outer surface, 2. Surface settlement curve, 3. Diaphragm wall, 4. Supporting surrounding beam, 5. Inner support of reinforced concrete in foundation pit, 6. Horizontal steel pipe, 7. Horizontal hole, 8 , geotextile bag, 9, horizontal grouting pipe, 10, binding tape, 11, grouting body, 12, horizontal grouting bag, 13, sealing cover, 14, basement floor, 15, water-proof sealing material, 16 , sealing gasket, 17, deformed underground pipe, 18, underground pipe, 19, oblique hole, 20, oblique grouting pipe, 21, oblique slurry bag, 22, oblique steel pipe, 23, adjacent underground continuous wall, 24, fixed end, 25, countersunk hole, 26, monitoring point, 27, horizontal bolt, 28, first construction hole, 29, drill pipe, 30, drill pipe clamp, 31, drilling rig, 32, foundation pit excavation surface.

Detailed ways

The specific embodiments of the present invention will be further described below with reference to the accompanying drawings. It should be stated here that the description of these specific embodiments is used to help the understanding of the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in the specific embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

As shown in FIG. 1 , FIG. 2 , FIG. 3 , FIG. 4 , FIG. 5 , FIG. 6 , FIG. 7 and FIG. 8 .

Existing foundation pit enclosure walls generally have two structures, an enclosure wall (not shown in the figure) consisting of an underground continuous wall 3 and a water-stop curtain on the outside and supporting piles on the inside.

The method for repairing the surface settlement outside the foundation pit enclosure wall or the deformation of the underground pipe in the present invention can be described as the repair method for the surface settlement outside the foundation pit enclosure wall or the repair method for the deformation of the underground pipe outside the foundation pit enclosure wall. It is called the method of repairing the surface settlement or the deformation of the underground pipe on the outer side of the retaining wall of the foundation pit, including the following construction steps:

(1) According to the prediction and evaluation data, one or more rows of steel pipes are pre-buried on the underground diaphragm wall 3 in the retaining wall of the foundation pit, each row is multiple, and each steel pipe is horizontal, that is, the horizontal steel pipe 6 Or the inclined state in which the inside of the foundation pit is high and the outside of the foundation pit is low is the inclined steel pipe 22 .

(2) Set up a plurality of monitoring points 26 in the settlement area of the surface 1 or the control area of the underground pipe 18 on the outer side of the retaining wall of the foundation pit. The monitoring points 26 are arranged in the radial and latitudinal directions, and the monitoring equipment is used to obtain the time base of the excavation of the foundation pit in a timely manner. The settlement value of the soil body on the surface 1 outside the retaining wall of the pit or the deformation settlement value of the underground pipe 18 or the horizontal displacement value of the underground pipe 18 deformation.

The outer surface 1 of the retaining wall of the foundation pit is also called the outer surface 1 of the foundation pit. The soil mass on the outer surface 1 of the retaining wall of the foundation pit is the soil mass below the surface settlement curve 2 of the outer surface 1 of the retaining wall of the foundation pit. The underground pipes 18 are various pre-buried underground pipes 18 in municipal engineering. The underground pipes 18 may also be referred to as underground pipes. The outer surface 1 is also called the outer surface. The foundation pit retaining wall is also called the foundation pit retaining structure.

(3) Determine the position and direction of the construction hole on the retaining wall of the foundation pit according to the height to be repaired, the lateral position and the horizontal or oblique direction obtained from the monitoring value: the first construction hole 28 on the underground diaphragm wall 3 is in the The buried steel pipe can be selected horizontally or obliquely. The first construction holes 28 are in one or more rows, and each row is plural. The second construction hole of the enclosure wall formed by the water-stop curtain on the outside and the support piles on the inside is selected and marked on the soil body in the gap between the support piles adjacent to the support piles, and the second construction hole is a Row or rows, each row is multiple, the second construction hole is horizontal, which is horizontal hole, or the oblique state where the inner side of the foundation pit is high and the outer side of the foundation pit is low is the oblique hole (waterproof curtain, support row The soil body of the gap of the pile, the supporting pile and the second construction hole on the gap soil body are not shown in the drawings). A horizontal or oblique trend may be referred to as a horizontal or oblique trend. The construction holes on the retaining wall of the foundation pit are generally located on the retaining wall of the foundation pit above the horizontal position of the basement floor 14 after the foundation pit has been dug. The construction holes, such as the first construction holes 28 or the second construction holes, may be in one row, or may be in multiple rows, such as two rows, three rows, or four rows. Each row is multiple, such as several, dozens, dozens or dozens and so on.

(4) Determine the length of the geotextile bag 8 and the length of the anchor rod set in the geotextile bag 8 and the grouting pipe according to the depth of the required drilling hole, the height of the soil body to be lifted or the distance to be traversed according to the monitoring value. The length and the diameter of each geotextile bag 8 in the multiple geotextile bags 8 formed by binding, wherein the grouting pipe is reserved for the length of the grouting pump (not shown in the figure of the grouting pump), and each geotextile bag 8 corresponds to One or more grouting holes on the grouting pipe (not shown in the grouting hole diagram). The anchor rod includes a horizontal anchor rod 27 and an oblique anchor rod (not shown in the figure). The grouting pipe includes a horizontal grouting pipe 9 and an oblique grouting pipe 20 .

(5), use the drilling rig 31 to drill the horizontal hole 7, put the horizontal grouting pipe 9, the horizontal bolt 27 and the multiple geotextile bags 8 extending in the axial direction in the horizontal hole 7, and grouting makes each The geotextile bag 8 is filled with cement slurry and the grouting body 11 after solidification constitutes a set of horizontal slurry pockets 12 to lift the subsidence soil body or the subsidence soil body or the lifting deformation underground pipe 17 on the outside of the foundation pit. The pulp pockets 12 are arranged in multiple rows, and each row is arranged in multiple groups. or

The oblique hole 19 is drilled by the drilling machine 31, the oblique grouting pipe 20, the oblique bolt and the multiple geotextile bags 8 extending in the axial direction are placed, and each geotextile bag 8 is filled with cement slurry and solidified after grouting. The grouting body 11 constitutes a set of oblique slurry sacks 21 to lift the deformed underground pipe 17 outside the foundation pit or cross the reset and deformed underground pipe 17. The oblique slurry sacks 21 are arranged in multiple rows, and each row has multiple groups. .

The lift can be called a bulge. The horizontal holes 7 or the oblique holes 19 may be in one row, or may be in multiple rows, such as two rows, three rows, or four rows. Each row may be multiple, such as several, dozens, dozens or dozens, etc.

The horizontal hole 7 consists of a horizontal bolt 27, a horizontal grouting pipe 9 and a plurality of axially arranged geotextile bags 8 filled with cement slurry and solidified. The pouches 12 can be in one row or in multiple rows, such as two rows, three rows or four rows, and each row can be in multiple groups, such as several groups, dozens of groups, dozens of groups, or dozens of groups.

The oblique hole 19 is a group of oblique slurry sacs composed of oblique bolts, oblique grouting pipes 20 and a plurality of axially arranged geotextile bags 8 filled with cement slurry and solidified grouting body 11. The bags 21 can be one row or multiple rows, such as two rows, three rows or four rows, and each row can be multiple groups, such as several groups, dozens of groups, dozens of groups or dozens of groups.

(6), grouting makes the steel pipe such as the first construction hole 28 at the outer end of the horizontal steel pipe 6 or the oblique steel pipe 22 to be blocked and solidified to facilitate water stop, and cut the steel pipe such as the horizontal steel pipe 6 or the oblique steel pipe 22. Grouting pipe. Or: grouting seals and solidifies the second construction hole on the water-stop curtain and the gap between the supporting piles adjacent to the supporting piles to facilitate water-stopping, and cut the grouting projecting out of the second construction hole inside the foundation pit. Slurry tube.

In step (1), the inner end of the foundation pit of each steel pipe, such as the horizontal steel pipe 6 or the oblique steel pipe 22, protrudes from the inner surface of the underground diaphragm wall 3. Before pre-embedding and after the grouting construction is completed, the steel pipe such as horizontal Tighten the sealing cover 13 to the inner end of the foundation pit of the steel pipe 6 or the inclined steel pipe 22 . Before pre-embedding, the outer end of the foundation pit of each steel pipe, such as the horizontal steel pipe 6 or the oblique steel pipe 22, is sealed with a temporary sealing material. The inner end of the foundation pit of each steel pipe is provided with a detachable sealing cover 13. The detachable type, such as threaded connection, can be provided with an inner thread in the inner hole of the inner end of the foundation pit of the steel pipe, and an outer thread on the outer circumference of the sealing cover 13. A sealing gasket 16 can also be set on the sealing cover 13 to seal the end face inside the steel pipe foundation pit and the stepped surface of the sealing cover 13 .

The steel pipe pre-embedding can be performed by welding the horizontal steel pipe 6 or the oblique steel pipe 22 to the predetermined position of the steel cage (the steel cage is not shown in the figure) in advance when the steel cage of the underground continuous wall 3 is made. The inner end of the foundation pit is pre-tightened and sealed with the sealing cover 13, and the outer end of the foundation pit of the steel pipe can be pre-sealed with zero-time sealing materials such as silk wool or asbestos. The sealing cover 13 of the pre-embedded steel pipe at the end is unscrewed and the sealing material at the outer end is drilled.

Drilling holes, placing grouting pipes, bolts, geotextile bags 8 and each steel pipe after the grouting construction is completed, that is, the horizontal steel pipe 6 or the first construction hole 28 of the oblique steel pipe 22, there is an anti-seepage on the outer end of the foundation pit. The water sealing material 15 is, for example, the cement slurry after grouting overflows and solidifies. Then, remove the cement slurry at the inner thread of the steel pipe to tighten the sealing cover 13 and compress the sealing gasket 16 . The water-proof sealing material 15 is also called a filling material. Each row of steel pipes can be understood here as all horizontal steel pipes 6 , or all oblique steel pipes 22 , or both horizontal steel pipes 6 and oblique steel pipes 22 . After drilling, placing grouting pipe, anchor rod 27, geotextile bag 8 and grouting, the sentence can be understood as follows: drilling, placing grouting pipe, placing anchor rod, placing geotextile bag 8 and grouting. After construction is complete.

In the multiple rows of steel pipes in step (1), the adjacent upper and lower rows of steel pipes are staggered: the adjacent upper and lower rows of steel pipes are not on the same vertical line. Expanding speaking, in the multiple rows of steel pipes in step (1) such as horizontal steel pipes 6, the adjacent upper and lower rows of steel pipes are staggered such as horizontal steel pipes 6: the adjacent upper and lower rows of steel pipes such as horizontal steel pipes 6 are not in the same lead. vertical line. Or, in the multiple rows of steel pipes of step (1) such as oblique steel pipes 22, adjacent upper and lower two rows of steel pipes are staggered such as inclined steel pipes 22: adjacent upper and lower rows of steel pipes such as oblique steel pipes 22 are not in the same vertical on-line. Or, in the multi-row steel pipes of step (1) such as horizontal steel pipes 6 or oblique steel pipes 22, adjacent upper and lower two rows of steel pipes such as horizontal steel pipes 6 and oblique steel pipes 22 are staggered: Steel pipes such as horizontal steel pipes 6 and oblique steel pipes 22 are not on the same vertical line.

In step (2), multiple monitoring points 26 in the radial and latitudinal directions, such as dozens, dozens or dozens of points, are set up, and the monitoring equipment is used to obtain values such as settlement or lateral movement or horizontal movement, so as to detect The inventive point of the present invention is to arrange the repair structures such as the grouting pipe and the pulp sac bag randomly. It is not difficult to understand, but the specific structure, monitoring equipment and specific monitoring method of the monitoring point 26 belong to the prior art. The electronic level with an accuracy of 0.3mm/km takes the surface monitoring base point with known elevation as the standard benchmark point. During monitoring, by measuring the elevation difference ΔH between each monitoring point and the benchmark point, that is, the base point, the standard elevation Δht of each monitoring point can be obtained, Then compare it with the last measured elevation, and the difference Δh is the settlement value of the measuring point. Another example is the method of measuring the horizontal displacement x of the underground pipe in the process of soil settlement in the prior art: measuring the buried depth h of the pipe during the pre-construction exploration process, and burying an inclinometer next to the pipe. After settlement, the inclination variable Δθ before and after settlement can be measured, and since x/h=tanΔθ, that is, x=h×tanΔθ, by bringing in the known h and Δθ, the horizontal displacement x of the pipeline during the settlement process can be obtained. As mentioned above, the specific structure, monitoring equipment and specific monitoring method of the monitoring point belong to the prior art, and will not be described here.

In step (3), each row of construction holes such as the first construction hole 28 and the second construction hole are arranged on the foundation pit enclosure wall between the upper and lower sides of the two rows of supporting enclosure beams 4, such as the water stop on the underground continuous wall 3 or on the outside Curtain plus inner supporting piles on the retaining wall.

FIG. 7 shows a schematic view of drilling an oblique hole 19 .

The drilling rig 31 can be a commercially available rock bolt and cable drilling rig crawler type KLD-200 hydraulic electric anchoring drilling rig.

Each row of construction holes is shown in Figure 1, Figure 2, Figure 4, Figure 5, and Figure 7. The first construction hole 28 is arranged between the upper and lower sides of the two rows of supporting beams 4. Figure 1, Figure 2 , Figure 4, Figure 5, Figure 7 shown on the underground continuous wall 3. In step (5), the repair of the settlement soil body on the outer surface 1 of the foundation pit or the reset or repair of the deformed underground pipe 17 is coordinated with the excavation work in the foundation pit: the excavation operation in the foundation pit is carried out to a row of construction holes such as the first construction After the excavation surface 32 of the foundation pit below the hole 28 or the surrounding beam 4 of the foundation pit below the second construction hole, the pouring work of the support 5 in the reinforced concrete of the foundation pit needs to be carried out. At this time, the excavation operation in the foundation pit is suspended and the foundation pit is waiting After the reinforced concrete inner support 5 reaches the predetermined strength, the soil is continued to be excavated downward, and the grouting construction of step (5) is performed at this position and this time point. In the actual construction process, the excavation surface 32 of the foundation pit can be used, and the excavation surface 32 of the foundation pit can be gradually excavated from top to bottom, and the construction is performed layer by layer. The drill rod 29 is fastened on the drill rod clamp 30, and the drill rod clamp 30 is installed on the drilling rig 31, and the drilling rig 31 is located on the excavation surface 32 of the foundation pit. Enter the drilling hole from the first construction hole 28. After the oblique hole 19 is drilled, place the multiple geotextile bags 8 formed by binding into the oblique hole 19 along with the oblique anchor rod and the oblique grouting pipe 20, and then inject The slurry forms a series of oblique slurry pockets 21 that reset the deformed underground pipes 17 outside the foundation pit, and then tighten the sealing cover 13 . The construction operation for the horizontal arrangement is also the same, only the angle is different. It is not difficult to understand that the specific operation of the above drilling also belongs to the prior art. For example, for soft soil, the soil in the hole can be replaced with mud to prevent the hole from collapsing, and the drill pipe 29 can be pulled out after the replaced mud is solidified.

The above-mentioned grouting body 11 is formed after the grouting slurry is solidified. It is not difficult to understand that the ratio of grouting slurry and the specific grouting operation also belong to the prior art. For example, the grouting slurry can be made of 42.5 grade ordinary Portland cement, and the water-cement ratio is 1:0.55. Low-pressure secondary grouting can be used for grouting. The primary grouting pressure is generally less than 0.6Mpa, and the secondary grouting pressure generally should not be less than 1.5Mpa. After the total volume, grouting can be continued for about 2 minutes, so as to make the filling volume better without breaking the bag, so that the technical effect of lifting the soil body or resetting the deformed underground pipe 17 is better.

In step (5), a plurality of horizontal slurry pockets 12 connected to a horizontal grouting pipe 9 are located at the depression of the ground surface 1 outside the foundation pit, as shown in Figures 1, 4, 5 and 7 The horizontal hole 7 of the soil body below the surface settlement curve 2 or the horizontal hole 7 of the soil body below the deformation underground pipe 17 on the outside of the foundation pit. A plurality of inclined slurry pockets 21 connected to an inclined grouting pipe 20 are located in the inclined holes 19 of the soil on the side of the deformed underground pipe 17 outside the foundation pit or in the soil below the deformed underground pipe 17 outside the foundation pit. Inside the oblique hole 19.

In step (5), the end of the horizontal bolt 27 in the horizontal hole 7 away from the retaining wall of the foundation pit is fixed in the counterbore 25 of the adjacent underground continuous wall 23, and the horizontal grouting pipe 9 also extends to grouting into the counterbore 25 for fixing. In other words, the end of the horizontal bolt 27 in the horizontal hole 7 away from the retaining wall of the foundation pit is the fixed end 24 . Specifically, there are two structures. One is to weld several anchoring nails at the top of the horizontal bolt located in the counterbore 25, and at the end of the construction hole, with the help of an auxiliary reinforcing rod and a hammer, knock the construction hole such as the first construction hole 28. At this end, the anchoring pin is fastened on the end wall of the counterbore 25, and then grouting is poured into the counterbore 25 through the grouting pipe and the fixing effect is achieved after solidification. The other is to locate the horizontal bolt 27 in the counterbore 25, and tap the end of the construction hole with the aid of an auxiliary reinforcing rod and a hammer at the end of the construction hole, as shown in Figure 6, so that the horizontal bolt 27 is located in the counterbore The end face of the end inside 25 is pushed to the end wall of the countersunk hole 25, and then the horizontal bolt at this end of the construction hole is temporarily axially limited. Press the end of the construction hole of the horizontal anchor rod, and the other end extends out of the end of the steel pipe foundation pit and is fixed by spot welding, and then grouting into the counterbore 25 through the grouting pipe and waits for solidification to achieve the fixing effect, and then grind it with a grinding wheel. Remove the solder joints and pull out the round steel.

It is not difficult to understand that the length of the bolt in the horizontal hole 7 or the oblique hole 19 and the length of the grouting pipe can be equal, and the geotextile bag 8 can be extended along the length of the bolt and the grouting pipe and is a complete bag. , after being bound on the horizontal bolt 27 and the horizontal grouting pipe 9 or the oblique bolt and the oblique grouting pipe 20 by the binding tape 10, a plurality of geotextile bags 8 connected in series along the axial direction are formed. The diameters can be equal, but generally, geotextile bags 8 with different diameters and/or lengths will be made on the construction site according to needs. As mentioned above, each geotextile bag 8 corresponds to a horizontal grouting pipe 9 or an oblique grouting pipe. At least one grouting port on 20, preferably a plurality of grouting ports are arranged along the circumference of the grouting pipe. It is not difficult to understand that the end of the grouting pipe away from the horizontal hole 7 or the oblique hole 19 is connected to a grouting pump or a grouting pump, and after the grouting is completed, it is generally approached from the construction hole such as the first construction hole to the anchor rod. Cut off at the place so as not to prevent the sealing cap 13 from being sealed. Of course, cutting is a very common operation, because the grouting pipe is generally a PE plastic pipe, which can be cut with an electric cutting knife extending into the steel pipe.

The following is a specific embodiment constructed by adopting the repair method of the present invention on the enclosure wall formed by the outer water-stop curtain and the inner support row piles: the foundation pit enclosure wall is the outer water stop curtain and the inner support row. For the retaining wall composed of piles, the construction holes are the second construction holes drilled on site in the soil of the gap between the inner supporting piles adjacent to the supporting piles and the outer water-stop curtain. In each second construction hole after drilling, placing grouting pipe, anchor rod, geotextile bag and grouting, there is an anti-seepage water sealing material (not shown in the structural diagram of this section). In this specific embodiment, except that the construction hole structure is different, for example, the grouting pipe without the steel pipe and the second construction hole is cut from the inner end of the foundation pit. The rest of the operations are the same as the above specific embodiments.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (7)

1. A method for repairing surface subsidence or deformation of an underground pipe outside a foundation pit enclosure wall is characterized by comprising the following steps: the method comprises the following construction steps:

(1) pre-burying one or more rows of steel pipes on the underground continuous wall in the foundation pit enclosure wall according to the prediction and evaluation data, wherein each row is provided with a plurality of steel pipes, and each steel pipe is in a horizontal state or in an inclined state that the inner side of the foundation pit is higher than the outer side of the foundation pit and is lower than the outer side of the foundation pit;

(2) a plurality of monitoring points are arranged in a surface subsidence area or an underground pipe control area outside the foundation pit enclosure wall, the monitoring points are arranged along the radial direction and the latitudinal direction, and monitoring equipment is adopted to timely acquire a surface soil body subsidence value or an underground pipe deformation horizontal movement value outside the foundation pit enclosure wall during foundation pit excavation;

(3) determining the position and the direction of a construction hole on the foundation pit enclosure wall according to the height position to be repaired, the transverse position and the horizontal direction or the oblique direction obtained according to the monitoring value: selecting first construction holes in the underground continuous wall from pre-buried steel pipes, wherein the first construction holes are arranged in one or more rows, and each row is provided with a plurality of first construction holes; a second construction hole of the enclosure wall formed by the waterproof curtain on the outer side and the supporting row piles on the inner side is selected and marked on soil bodies in gaps between the supporting piles adjacent to the supporting row piles, the second construction holes are arranged in one row or multiple rows, each row is multiple, and the second construction holes are in a horizontal state or in an inclined state that the inner side of the foundation pit is higher than the outer side of the foundation pit and is lower than the outer side of the foundation pit;

(4) determining the length of the geotextile bags, the length of anchor rods sleeved in the geotextile bags, the length of a grouting pipe and the diameter of each geotextile bag in a plurality of geotextile bags formed by binding according to the depth of the holes to be drilled, the height of the soil body to be lifted or the distance of the transverse movement, which are obtained according to the monitoring values, wherein the grouting pipe is reserved with the length connected with a grouting pump, and each geotextile bag corresponds to one or more grouting holes in the grouting pipe;

(5) drilling a horizontal hole by using a drilling machine, placing a horizontal grouting pipe, a horizontal anchor rod and a plurality of geotechnical cloth bags extending along the axial direction, and grouting to ensure that each geotechnical cloth bag is filled with cement slurry and solidified grouting body forms a group of horizontal grouting bag to lift the sunken soil body on the ground surface outside the foundation pit or lift the deformed underground pipe, wherein the number of the horizontal grouting bags is multiple, and each group is multiple; or

Drilling an oblique hole by using a drilling machine, placing an oblique grouting pipe, an oblique anchor rod and a plurality of geotechnical cloth bags extending along the axial direction, and grouting to ensure that each geotechnical cloth bag is filled with cement slurry and solidified grouting forms a group of oblique slurry bag to lift the deformed underground pipe outside the foundation pit or transversely support the deformed underground pipe, wherein the oblique slurry bags are arranged in a plurality of rows, and each row is a plurality of groups;

(6) grouting to enable a first construction hole at the outer side end of the steel pipe to be plugged and solidified so as to facilitate water stopping, and cutting a grouting pipe in the steel pipe; or: and (3) plugging and solidifying a second construction hole in the soil body of the gap between the waterproof curtain and the adjacent supporting pile of the supporting row pile by grouting to facilitate water stopping, and cutting a grouting pipe extending out of the inner side of the foundation pit of the second construction hole.

2. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1, wherein: in the step (1), the inner side of the foundation pit of each steel pipe is protruded inwards to the inner surface of the underground continuous wall, and a sealing cover is screwed at the inner side end of the foundation pit of the steel pipe before pre-embedding and after grouting construction is completed; and plugging the outer side end of the foundation pit of each steel pipe by using a temporary plugging material before pre-burying.

3. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1, wherein: in the multi-row steel pipes in the step (1), two rows of adjacent steel pipes are arranged in a staggered manner: the adjacent upper and lower rows of steel pipes are not on the same plumb line.

4. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1, wherein: in the step (3), each row of construction holes are arranged on the foundation pit enclosure wall between the upper part and the lower part of the two rows of support enclosing beams.

5. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1, wherein: in the step (5), the restoration of the ground surface settlement soil body outside the foundation pit or the restoration of the deformed underground pipe is matched with the excavation engineering in the foundation pit: and (3) after the excavation operation in the foundation pit is carried out to the excavation surface of the foundation pit below the foundation pit girth beam below the row of construction holes, pouring the reinforced concrete inner support of the foundation pit, suspending the excavation operation in the foundation pit at the moment, continuing excavating downwards after the reinforced concrete inner support of the foundation pit reaches the preset strength, and carrying out the construction in the step (5) at the position and at the time point.

6. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1, wherein: in the step (5), a plurality of horizontal grouting bags connected to one horizontal grouting pipe are positioned in horizontal holes of soil below the subsidence of the ground surface outside the foundation pit or horizontal holes of soil below the deformed underground pipe outside the foundation pit; the plurality of inclined grouting bags connected to one inclined grouting pipe are positioned in inclined holes of soil bodies on the lateral parts of the deformed underground pipes on the outer sides of the foundation pits or in inclined holes of soil bodies below the deformed underground pipes on the outer sides of the foundation pits.

7. The method for repairing settlement of the ground surface outside the foundation pit enclosure wall or deformation of the underground pipe according to claim 1 or 6, wherein: in the step (5), one end, far away from the foundation pit enclosure wall, of the horizontal anchor rod in the horizontal hole is fixed in the counter bore of the adjacent underground continuous wall, and the horizontal grouting pipe also extends into the counter bore to inject grouting into the counter bore for fixing.

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