Existing building lifting method based on additional settlement generated in grouting process

Abstract

According to the existing building lifting method based on additional settlement generated in the grouting process, settlement of one side of an existing building is larger than that of the other side of the existing building, additional settlement exists on the large-settlement side of the existing building, a supporting curtain is arranged, the portion, prone to additional settlement, of a large-settlement area is blocked, slurry is prevented from being lost outwards during follow-up grouting lifting, and the problem that the existing building is prone to additional settlement is solved. The lifting force is effectively restrained in an area needing to be lifted, and lateral support is provided; the anchor point is locked through local grouting, and then block-by-block circulating lifting is carried out; the structural stress of the soft foundation in the main lifting area tends to be stable firstly and does not continue to deteriorate, the problem of additional settlement is avoided, and the lifting precision is better guaranteed; according to the method, the main lifting area, the transition area and the stable area are arranged, space isolation and differential control are conducted on the grouting area, the pain points of global homogenization, stress unrestraint and risk management and control difficulty of traditional grouting are improved from the source, and generation of additional settlement can be eliminated easily.

Description

Technical Field

[0001] This invention relates to the field of building grouting and lifting technology, and in particular to a method for lifting existing buildings based on the additional settlement generated during the grouting process. Background Technology

[0002] When buildings experience uneven settlement, grouting is typically used for reinforcement and lifting, usually proceeding from the side with greater settlement to the side with less settlement. However, lifting from the side with greater settlement can lead to further settlement on that side, a phenomenon known as additional settlement. This occurs frequently in engineering practice, severely impacting the effectiveness of grouting and lifting, and seriously affecting the safety of the building. Currently, traditional grouting systems are unsuitable for complex geological formations and require precise lifting, failing to address the issue of additional settlement during grouting and lacking systematic analysis and solutions. Therefore, a targeted grouting method is needed to effectively address the technical challenges of additional settlement and precise lifting during the grouting process. Summary of the Invention

[0003] This invention provides a method for lifting existing buildings based on the additional settlement generated during the grouting process, in order to solve technical problems such as additional settlement during the grouting process, zoned grouting, and precise lifting.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A method for lifting existing buildings based on additional settlement during grouting, where one side of the existing building has greater settlement than the other, and the side with greater settlement has additional settlement, is described below: Step 1: Perform grouting zoning. Based on the numerical simulation data of settlement displacement, perform grouting zoning, dividing the grouting area into the main uplift zone, transition zone, and stable zone. The main uplift zone is the side with large settlement, the stable zone is the side with small settlement, and the transition zone is the middle area between the side with large settlement and the side with small settlement. Step 2: Forming a support curtain. Grouting is performed through the curtain grouting holes at the locations of additional settlement around the main lifting zone to form a support curtain. The support curtain is a lateral support barrier wall. It supports the surrounding soil and prevents the surrounding soil from sliding and settling more rapidly during the grouting process. It also prevents the grout from flowing outward during subsequent grouting and lifting, and effectively confines the lifting force within the main lifting zone. Step 3: Grouting is performed in the intermediate transition zone through transition grouting holes to reinforce the foundation and form a grouting isolation layer. The isolation layer blocks the lateral transmission of stress during grouting in the main uplift zone. Step 4: Based on the function of the building rooms, divide the main lifting area into n blocks. According to the principle of settlement from large to small, number all blocks in sequence. Define at least the first two blocks with large settlement as anchor block one, and define the blocks on both sides of the expansion joint as anchor block two. Step 5: First, grout and lift anchor point plate 1 and anchor point plate 2 through the main grouting hole. After anchor point plate 1 and anchor point plate 2 are stabilized, grout and lift the remaining plates in sequence. Step 6: Excess pressure is generated during grouting in the main lifting zone. The pressure accumulates in the foundation and is transmitted to the stable zone, which will lift accordingly. Therefore, a row of pressure relief holes is arranged at the outer edge of the stable zone, with the pressure relief holes aligned with the longitudinal wall. Step 7: The stable zone is mainly reinforced. Depending on the changes in the displacement of the monitoring points, it may be slightly raised or not raised at all. Low-pressure grouting is used when grouting the grouting holes in the stable zone. This completes the grouting and raising of the existing building based on the additional settlement generated during the grouting process.

[0005] Additional settlement occurs in areas where the soil directly beneath the main uplift zone is weak or partially hollowed out. In these additional settlement zones, pre-grouting prevents the grout from providing effective support and exacerbates the disturbance, leading to further settlement.

[0006] Furthermore, the area of ​​the main lifting zone is not less than one-third of the area of ​​the area to be lifted, and the area of ​​the isolation zone is not greater than one-third of the area of ​​the area to be lifted.

[0007] Furthermore, in step five, when grouting the anchor point slab, the grouting force is concentrated to control it and prevent further subsidence. The grouting holes are arranged along the length of the wall, with a spacing of 1.5~3.0m. An intermittent grouting process is used, with a grout injection rate of 1.1~2.0m per hole. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

[0008] Furthermore, during the grouting of the second anchor point panel, after the first anchor point panel has stabilized, the grouting force is concentrated to control it and prevent further subsidence. The grouting holes are arranged along the length of the wall, with a spacing of less than 1.5~3m. An intermittent grouting process is used, with a grout injection rate of 1.1~2.0m per hole. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

[0009] Furthermore, in step five, the remaining slabs are grouted progressively according to their settlement, from largest to smallest. The main grouting holes are arranged along the length of the wall, with a spacing of 1.5~3.0m. An intermittent grouting process is used, with a grout injection rate of 1.1~2.0m per hole. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

[0010] Furthermore, during the sequential grouting and lifting of the remaining slabs, a segmented cyclic grouting and lifting method was also adopted. Following the principle of decreasing settlement, all slabs were sequentially numbered and grouted and lifted. In the first round of lifting, each slab was lifted only by a certain amount, which was 1 / 5 of the settlement difference. After completion, a second round of lifting was performed, with the same lifting amount, and this process was repeated until the lifting met the engineering requirements. Throughout the process, the displacement changes of the corresponding monitoring points were monitored continuously. Simultaneously, pressure relief holes were used to release pressure in conjunction with the lifting of the side with the largest settlement.

[0011] Furthermore, the grouting holes in the stable zone are arranged along the length of the wall with a spacing of more than 5m, and low-pressure grouting is used during grouting. Pressure relief holes are installed on the outside of the stable zone. The holes are aligned with the longitudinal wall, with a diameter of 50-80mm and a depth consistent with the grouting holes.

[0012] Furthermore, the supporting curtain is arranged in a strip, L-shape, or U-shape; the grouting holes of the curtain are spaced apart along the length of the supporting curtain, with a hole spacing of less than 3m and a grouting pressure of 0.2MPa (low-pressure grouting); the transition grouting holes in the transition zone are arranged in a strip along the isolation direction, with a hole spacing of less than 3m and a grouting pressure of 0.2MPa (low-pressure grouting).

[0013] Furthermore, when there is an expansion joint in the foundation, the foundations on both sides of the expansion joint do not share grouting holes. The distance between the grouting hole and the edge of the expansion joint is ≥1.5m. In soft soil layers, the distance between the grouting hole and the edge of the expansion joint is ≥2m. During lifting, the foundations on both sides of the expansion joint are independently controlled, and the joints are monitored collaboratively. At the same time, the grouting pressure is prevented from acting directly on both sides of the joint, which could lead to cracking of the concrete at the joint edge. The grouting holes include main grouting holes, transition grouting holes, and stabilizing grouting holes.

[0014] The beneficial effects of this invention are reflected in: 1) This invention uses a support curtain to enclose areas prone to additional settlement in large settlement areas, preventing grout from flowing outward during subsequent grouting and lifting, and effectively confining the lifting force within the area to be lifted and providing lateral support. 2) In this invention, the main lifting zone is first grouted to lock the anchor point slabs, and then grouted block by block to maintain settlement stability. After the settlement has stabilized for a period of time, the blocks are lifted in a cyclic manner. This allows the structural stress of the weak foundation in the main lifting zone to stabilize first, so that it will no longer continue to deteriorate and generate additional settlement problems. Under the premise of safety and controllability, the blocks are lifted in a cyclic manner, and the force transmission will be more uniform, which better ensures the lifting accuracy. 3) The transition zone set by the present invention physically isolates the main lifting zone from the stable zone, avoiding the disorderly transmission of grouting pressure and grout diffusion to the stable zone, and reducing the phenomenon of cascading lifting or stress superposition in the core zone. 4) The low-pressure, large-hole-spacing grouting in the stable zone of this invention is mainly for reinforcement. This allows for precise control of the uplift and prevents "overcorrection". If the stable zone is not separately divided and "uniform grouting throughout the area" is used, it is easy to cause excessive uplift in the low settlement area, which can lead to cracking of the building structure.

[0015] 5) By setting up a main lifting zone, a transition zone, and a stabilization zone, this invention provides "spatial isolation and differentiated control" for the grouting area, thereby improving the pain points of traditional grouting, such as "homogeneity across the entire area, lack of stress constraint, and difficulty in risk management," and helping to eliminate additional settlement. Therefore, this application solves the technical problems of additional settlement, zoned grouting, and precise lifting during the grouting process. Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention; the main objectives and other advantages of the invention can be realized and obtained by means of the methods particularly pointed out in the description. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the construction of lifting an existing building based on the additional settlement that occurs during the grouting process; Figure 2 This is the initial settlement displacement diagram from the numerical simulation; Figure 3 This is a grouting zoning diagram; Figure 4 This is a diagram showing the layout of the grouting holes; Figure 5 This is a schematic diagram of the grouting blocks in the main lifting zone.

[0017] Attached reference numerals: 1-Main building structure, 2-Building foundation, 3-Curtain grouting hole, 4-Supporting curtain, 5-Main grouting hole, 6-Main lifting zone, 7-Transition grouting hole, 8-Transition zone, 9-Stabilizing grouting hole, 10-Stabilizing zone, 11-Pressure relief hole, 12-Backfill layer, 13-Loess-like silt layer, 14-Silty clay layer, 15-Slab, 16-Anchor point slab one, 17-Anchor point slab two, 18-Expansion joint. Detailed Implementation

[0018] The technical solutions of the present invention will be described in detail below through embodiments. The following embodiments are merely exemplary and can only be used to explain and illustrate the technical solutions of the present invention, and should not be construed as limiting the technical solutions of the present invention.

[0019] A residential building project has 18 floors above ground and 1 floor below ground. It is a shear wall structure with a raft foundation. The foundation depth is 6.15m. The main building 1 is 65.05m long, 10.45m wide, and 52.75m high, consisting of 3 units. Units 1 and 2 have expansion joints. The building foundation 2 is a raft foundation with a raft slab thickness of 800mm. The raft slab is 67.25m long and 12.2m wide. The top elevation of the raft slab is -5.35m, the bottom elevation is -6.15m, and ±0.000 corresponds to an absolute elevation of 1746.80m. Based on the on-site investigation, the foundation soil consists of, from top to bottom, a fill layer 12, a loess-like silt layer 13, and a silty clay layer 14. The loess-like silt layer 13 is primarily collapsible loess. The soil between piles has not completely eliminated collapsibility, and its compaction coefficient does not meet design requirements. Furthermore, prior to construction, a trench was excavated and repaired on the north side of the building. The trench was approximately 3.3m deep and 4.0m wide, and with continuous rainfall, the trench lacked any covering, waterproofing, or drainage measures, raising concerns about potential pipe leaks and rainwater seepage into the foundation. These factors may have caused uneven settlement. Subsequent pre-grouting reinforcement and lifting treatment was performed on the foundation. However, during grouting on the side with the largest settlement, a phenomenon of further settlement occurred. To address this additional settlement, a grouting method is proposed to resolve this issue.

[0020] Combination Figures 1 to 5 As shown, this further illustrates the method for lifting existing buildings based on the additional settlement generated during the grouting process, wherein... Figures 3 to 5 The arrow on one side indicates the direction of building settlement tilt. If an existing building has greater settlement on one side than the other, and the side with greater settlement has additional settlement, the specific steps are as follows: Step 1: Perform grouting zoning. Based on the numerical simulation data of settlement displacement, perform grouting zoning, dividing the grouting area into the main lifting zone 6, the transition zone 8, and the stabilization zone 10. The main lifting zone 6 is the side with large settlement, the stabilization zone 10 is the side with small settlement, and the transition zone 8 is the middle area between the side with large settlement and the side with small settlement. The area of ​​the main lifting zone 6 is not less than one-third of the area to be lifted, and the area of ​​the isolation zone is not greater than one-third of the area to be lifted.

[0021] In this embodiment, the area where the additional settlement occurs is a weak or partially hollowed-out area of ​​soil directly below the main uplift zone 6. In the area where the additional settlement occurs, the grout cannot form an effective supporting force through pre-grouting, and it will aggravate the disturbance and cause settlement again.

[0022] In this embodiment, the grouting area is the area enclosed by extending 2m outward from each side of the outer edge of the raft slab. The main lifting zone 6 has a width of 6.4m and a length of 71.25m; the isolation zone has a width of 3.9m and a length of 71.25m; and the stabilization zone 10 has a width of 5.9m and a length of 71.25m.

[0023] Step 2: Forming the support curtain 4. Grouting is performed through the curtain grouting holes 3 at the additional settlement points on the periphery of the main lifting zone 6 to form the support curtain 4. The support curtain 4 is a lateral support barrier wall. The support curtain is used to support the surrounding soil and prevent the surrounding soil from sliding and settling more severely during the grouting process, as well as to prevent the grout from flowing outward during subsequent grouting and lifting, and to effectively confine the lifting force inside the main lifting zone 6.

[0024] In this embodiment, the supporting curtain 4 is arranged in an L-shape, but it can also be arranged in a strip or U-shape, or lateral support and blocking can be set according to the pattern of the additional settlement zone; the curtain grouting holes 3 are spaced apart in the length direction of the supporting curtain 4, with a hole spacing of less than 3m, and the grouting pressure is 0.2MPa low-pressure grouting.

[0025] Step 3: Grouting is performed in the intermediate transition zone 8 through the transition grouting holes 7 to reinforce the foundation, forming a grouting isolation layer. This isolation layer blocks the lateral stress transmission during grouting in the main uplift zone 6. The transition grouting holes 7 in the transition zone 8 are arranged in a strip shape in the isolation direction, with a hole spacing of less than 3m, and the grouting pressure is 0.2MPa low-pressure grouting. In soft soil strata, this isolation layer can reduce the stress received on the side with less settlement by more than 60%, and the setting time and diffusion range of the grout used are controllable.

[0026] Step 4: Based on the function of the building rooms, divide the main lifting area 6 into n blocks. According to the principle of settlement from large to small, number all the blocks 15 in sequence. Define the first two blocks 15 with large settlement as anchor block one 16, and define the blocks 15 on both sides of the expansion joint 18 as anchor block two 17. Step 5: First, grout and lift anchor point 16 and anchor point 2 17 through the main grouting hole 5. After anchor point 16 and anchor point 2 17 are stabilized, grout and lift the remaining 15 in sequence. In step five, when grouting anchor point slab 16, concentrate the grouting force to control it and prevent further subsidence. Grouting holes are arranged along the length of the wall, with a spacing of 1.5~3.0m. An intermittent grouting process is used, with a grout injection rate of 1.1~2.0m per hole. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

[0027] In this embodiment, when grouting anchor point slab 17, after anchor point slab 16 has stabilized, the grouting force is concentrated to control it and prevent further subsidence. The grouting holes are arranged along the length of the wall, with a hole spacing of less than 1.5~3m. An intermittent grouting process is adopted during grouting, with a single hole grout injection rate of 1.1~2.0m. 3Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the monitoring points in the corresponding area. Among them, the "room panel" and "elevator shaft panel" with larger settlement are defined as anchor panel one 16, and the panels 15 on both sides of the expansion joint 18, "room panel" and "room panel" are defined as anchor panel two 17.

[0028] In this embodiment, in step five, the remaining slabs 15 are grouted progressively according to the settlement from largest to smallest; the main grouting holes 5 are arranged along the length of the wall, with a hole spacing of 1.5~3.0m, and an "intermittent grouting" process is adopted during grouting, with a single hole grout injection rate of 1.1~2.0m. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

[0029] In this embodiment, while the remaining slabs 15 are sequentially grouted and lifted, a segmented cyclic grouting and lifting method is also adopted. Following the principle of decreasing settlement, all slabs 15 are sequentially numbered and grouted and lifted. In the first round of lifting, each slab 15 is lifted only by a certain amount, which is 1 / 5 of the settlement difference. After completion, a second round of lifting is performed, with the same lifting amount, and this process is repeated until the lifting meets the engineering requirements. Throughout the process, the displacement changes of the corresponding monitoring points are monitored continuously. Simultaneously, pressure relief holes 11 are used to release pressure in conjunction with the lifting of the side with the largest settlement.

[0030] Step 6: Excess pressure is generated during grouting in the main lifting zone 6. The pressure accumulates in the foundation and is transmitted to the stable zone 10, which will lift accordingly. Therefore, a row of pressure relief holes 11 are arranged at the outer edge of the stable zone 10, and the pressure relief holes 11 are set in alignment with the longitudinal wall.

[0031] In this embodiment, the stabilization grouting holes 9 in the stabilization zone 10 are arranged along the length of the wall, with a spacing of more than 5m, and low-pressure grouting is performed during grouting. Pressure relief holes 11 are provided on the outer side of the stabilization zone 10, with the holes aligned with the longitudinal wall, a diameter of 50-80mm, and a depth consistent with the stabilization grouting holes 9. Step 7: The stabilization zone 10 is mainly reinforced. Depending on the changes in the displacement of the monitoring points, it is slightly raised or not raised at all. Low-pressure grouting is used when grouting the stabilization grouting holes 9 in the stabilization zone 10. This completes the grouting and raising of the existing building based on the additional settlement generated during the grouting process.

[0032] In addition, when there is an expansion joint 18 in the foundation, the foundations on both sides of the expansion joint 18 do not share grouting holes. The distance between the grouting hole and the edge of the expansion joint 18 is ≥1.5m. In soft soil layers, the distance between the grouting hole and the edge of the expansion joint 18 is ≥2m. During the lifting, the foundations on both sides of the expansion joint 18 are independently controlled and monitored collaboratively between the joints. At the same time, the grouting pressure is prevented from acting directly on both sides of the joint, which could lead to cracking of the concrete at the joint edge. The grouting holes include the main grouting hole 5, the transition grouting hole 7, and the stabilizing grouting hole 9.

[0033] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for lifting existing buildings based on additional settlement generated during grouting, characterized in that, If an existing building experiences greater settlement on one side than the other, and the side with greater settlement also experiences additional settlement, the specific steps are as follows: Step 1: Perform grouting zoning. Based on the numerical simulation data of settlement displacement, perform grouting zoning and divide the grouting range into the main lifting zone (6), the transition zone (8), and the stable zone (10). The main lifting zone (6) is the side with large settlement, the stable zone (10) is the side with small settlement, and the transition zone (8) is the middle area between the side with large settlement and the side with small settlement. Step 2: Forming a support curtain (4). Grouting is performed through the curtain grouting holes (3) at the location of additional settlement on the periphery of the main lifting zone (6) to form a support curtain (4). The support curtain (4) is a lateral support barrier wall. The support curtain is used to support the surrounding soil and prevent the surrounding soil from sliding and sinking more intensely during the grouting process. It is also used to block the grout from flowing outward during subsequent grouting and lifting, and to effectively confine the lifting force inside the main lifting zone (6). Step 3: In the intermediate transition zone (8), the foundation is reinforced by grouting through the transition grouting hole (7) to form a grouting isolation layer. The isolation layer blocks the lateral transmission of stress during grouting in the main uplift zone (6). Step 4: Based on the function of the building rooms, divide the main lifting area (6) into n blocks. According to the principle of settlement from large to small, number all the blocks (15) in sequence. Define the first two blocks (15) with large settlement as anchor block one (16), and define the blocks (15) on both sides of the expansion joint (18) as anchor block two (17). Step 5: First, grout and lift anchor point plate 1 (16) and anchor point plate 2 (17) through the main grouting hole (5). After anchor point plate 1 (16) and anchor point plate 2 (17) are stabilized, grout and lift the remaining plates (15) in sequence. Step 6: Excess pressure is generated during grouting in the main lifting zone (6). The pressure accumulates in the foundation and is transmitted to the stable zone (10), which will lift accordingly. Therefore, a row of pressure relief holes (11) is arranged at the outer edge of the stable zone (10), and the pressure relief holes (11) are aligned with the longitudinal wall. Step 7: The stable zone (10) is mainly reinforced. Depending on the change in the displacement of the monitoring point, it is slightly raised or not raised at all. Low-pressure grouting is used when grouting the stable grouting hole (9) of the stable zone (10). This completes the grouting and raising of the existing building based on the additional settlement generated during the grouting process.

2. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, The area where the additional settlement occurs is the area directly below the main uplift zone (6) where the soil is weak or partially hollowed out; the area where the additional settlement occurs cannot form an effective support force through pre-grouting, and will aggravate the disturbance and cause settlement again.

3. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, The area of ​​the main lifting zone (6) is not less than one-third of the area of ​​the area to be lifted, and the area of ​​the isolation zone is not greater than one-third of the area of ​​the area to be lifted.

4. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, In step five, when grouting anchor point slab one (16), the grouting force is concentrated to control it and prevent it from sinking further. The grouting holes are arranged along the length of the wall, with a hole spacing of 1.5~3.0m. The "intermittent grouting" process is adopted during grouting, and the grout injection rate of a single hole is 1.1~2.0m. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

5. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 4, characterized in that, When grouting anchor point slab two (17), after anchor point slab one (16) has stabilized, the grouting force is concentrated to control it and prevent it from sinking further. The grouting holes are arranged along the length of the wall, with a hole spacing of less than 1.5~3m. The "intermittent grouting" process is adopted during grouting, and the grout injection rate of a single hole is 1.1~2.0m. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

6. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 5, characterized in that, In step five, the remaining slabs (15) are grouted gradually according to the settlement from largest to smallest; the main grouting holes (5) are arranged along the length of the wall, with a hole spacing of 1.5~3.0m. During grouting, an "intermittent grouting" process is adopted, and the grout injection rate per hole is 1.1~2.0m. 3 Grouting is carried out at a rate of / h until the settlement rate reaches zero and is maintained at this state for more than two hours. Grouting is then stopped to allow the grout to solidify. Subsequent monitoring is conducted on the displacement changes of the corresponding monitoring points in the area.

7. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 6, characterized in that, When the remaining sections (15) are grouted and lifted in sequence, the grouted and lifted sections are also grouted in a cyclic manner. According to the principle of settlement from large to small, all sections (15) are numbered in sequence and grouted and lifted. In the first round of lifting, each section (15) is lifted by a certain amount, which is 1 / 5 of the settlement difference. After completion, the second round of lifting is carried out, and the lifting amount is the same as before. This process is repeated until the lifting meets the engineering requirements. During the above process, the displacement change of the monitoring points in the corresponding area is monitored at any time. At the same time, the pressure relief hole (11) is used to relieve pressure and cooperate with the lifting of the side with large settlement.

8. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, The grouting holes (9) in the stable zone (10) are arranged along the length of the wall with a spacing of more than 5m. Low-pressure grouting is used during grouting. Pressure relief holes (11) are set on the outside of the stable zone (10). The pressure relief holes (11) are aligned with the longitudinal wall, with a diameter of 50-80mm and a depth consistent with the grouting holes (9).

9. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, The supporting curtain (4) is arranged in a strip, L-shape or U-shape; the curtain grouting holes (3) are spaced apart along the length of the supporting curtain (4), with a hole spacing of less than 3m and a grouting pressure of 0.2MPa low pressure grouting; the transition grouting holes (7) in the transition zone (8) are arranged in a strip along the isolation direction, with a hole spacing of less than 3m and a grouting pressure of 0.2MPa low pressure grouting.

10. The method for lifting existing buildings based on additional settlement generated during grouting as described in claim 1, characterized in that, When there is a deformation joint (18) in the foundation, the foundations on both sides of the deformation joint (18) do not share the grouting hole. The distance between the grouting hole and the edge of the deformation joint (18) is ≥1.5m. In soft soil, the distance between the grouting hole and the edge of the deformation joint (18) is ≥2m. During the lifting, the foundations on both sides of the deformation joint (18) are independently controlled and monitored in coordination between the joints. At the same time, the grouting pressure is avoided from acting directly on both sides of the joint, which may cause the concrete at the joint edge to crack. The grouting hole includes the main grouting hole (5), the transition grouting hole (7), and the stabilizing grouting hole (9).

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