Vertical radial rigid sleeve valve pipe bundle grouting control settlement method

Abstract

The application discloses a vertical-diameter rigid sleeve valve pipe bundle grouting control settlement method, which comprises the following steps: marking and drilling overflow holes on at least three steel pipes with increasing lengths to form a rigid sleeve valve pipe bundle by combination and fixation; marking the positions of a plurality of grouting control settlement holes at an initial support arch part and vertically drilling the holes to a set depth; binding grouting pipes and exhaust pipes on the rigid sleeve valve pipe bundle, sending the pipes into the grouting control settlement holes, sealing the holes and pouring shell materials; installing settlement observation points and convergence observation points at set positions to monitor settlement data of a control settlement section in real time; when the settlement data reaches a critical settlement value, grouting is performed, the grouting is performed in the order from short to long according to the lengths of the steel pipes in the rigid sleeve valve pipe bundle, one rigid sleeve valve pipe is used each time, other rigid sleeve valve pipes are used as standby, the settlement data is monitored in real time during the grouting process, the grouting is stopped when the monitored settlement data reaches a requirement, and the whole stratum of the control settlement section is completed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of grouting reinforcement and settlement control in underground engineering, and particularly relates to a grouting settlement control method. BACKGROUND

[0002] With the development of underground engineering such as tunnels, subways, pipe corridors, etc., route selection is becoming more and more difficult. After the excavation of underground engineering, the deformation of the surrounding stratum often occurs, which leads to the settlement deformation of the ground surface or other nearby buildings. As a result, more and more high-risk projects with high settlement control requirements are emerging. At present, the methods for controlling settlement are basically pre-control and in-process control. The stratum is pre-reinforced by grouting before excavation, and then the excavation is supported and backfilled by grouting. However, these methods still cannot avoid the occurrence of settlement deformation, and cannot control the settlement deformation.

[0003] There is a great demand for post-control settlement technology. An effective method is urgently needed to change the current situation of controlling settlement after excavation and support, and to combine with pre-control and in-process control to achieve precise control of settlement and reduce or eliminate the risk of settlement.

[0004] For example, a bridge foundation directional grouting settlement control method disclosed in Chinese Patent Application No. 201810990988.9 includes: positioning a to-be-grouted area and vertically drilling a plurality of vertical grouting holes from the construction surface to the inside of the to-be-grouted area; lowering a sleeve valve pipe into the vertical grouting hole, and injecting a casing material into the gap between the outer wall of the sleeve valve pipe and the inner wall of the vertical grouting hole; lowering a grouting core pipe into the sleeve valve pipe by a winch for directional grouting, wherein the grouting core pipe includes a first segment grouting core pipe and a second segment grouting core pipe connected to each other, the first segment grouting core pipe is cut from a hot-rolled seamless steel pipe, the second segment grouting core pipe is made of a galvanized pipe, the first segment grouting core pipe is positioned in the to-be-grouted section of the vertical grouting hole, and the second segment grouting core pipe is positioned in the non-grouting section of the vertical grouting hole; and repeating step 3 to implement grouting of all vertical grouting holes in sequence. However, the bridge foundation directional grouting settlement control method still has the following shortcomings or deficiencies: (1) the method cannot achieve post-control settlement; (2) the method cannot control the settlement deformation of the stratum.

[0005] For example, the Chinese patent application No. 201010518332.0 discloses a method for controlling settlement of embankment transverse drilling and light replacement under normal traffic condition, which adopts drilling or chiseling hole forming technology to form a transverse hole in embankment at one side or both sides of roadbed slope. The hole is inclined downward at a certain angle to facilitate the pouring of light material. The light material is poured into the hole and solidified to form light replacement material. A sleeve can be first placed in the hole. The light material or non-backfill material is poured into the sleeve to ensure hole forming quality and avoid light material diffusion. However, the invention still cannot achieve the effect of controlling settlement afterwards.

[0006] Therefore, it is an urgent problem to provide a vertical and radial rigid sleeve valve pipe bundle grouting control settlement method which can precisely control settlement and reduce or eliminate settlement risk. SUMMARY

[0007] The present application aims to provide a vertical and radial rigid sleeve valve pipe bundle grouting control settlement method (referred to as CGK technology) which can be operated in parallel with hole excavation and support. During monitoring, when the measurement data reaches the control requirement, the vertical and radial rigid sleeve valve pipe bundle grouting control settlement is used to achieve the design requirement.

[0008] In order to achieve the above-mentioned purpose, the present application provides a vertical radial rigid sleeve valve pipe bundle grouting control settlement method, comprising: (1) cutting at least three steel pipes with increasing lengths, setting the length difference as 2-5 meters, marking the position of the overflow hole on each steel pipe and drilling the overflow hole, installing the stop valve sleeve at each overflow hole, processing one end of each steel pipe into a sharp head and the other end into a screw thread to form a rigid sleeve valve pipe, and combining and fixing at least three rigid sleeve valve pipes to form a rigid sleeve valve pipe bundle; (2) marking the position of a plurality of grouting control settlement holes at the initial support arch of the control settlement mileage, drilling a hole at each grouting control settlement hole at an angle perpendicular to the initial support arch to a set depth; (3) binding the grouting pipe and the exhaust pipe on the rigid sleeve valve pipe bundle, then sending the rigid sleeve valve pipe bundle, the grouting pipe and the exhaust pipe into the grouting control settlement hole, then sealing the grouting control settlement hole and fixing the rigid sleeve valve pipe bundle, the grouting pipe and the exhaust pipe; (4) after the sealing material reaches the required strength, pouring the casing material through the grouting pipe, closing the exhaust pipe when the grouting pipe leaks, and completing the pouring of the casing material; (5) after the support is completed, installing the settlement observation point and the convergence observation point at the set position, recording the initial data, and real-time monitoring the change of the settlement data of the control settlement mileage; (6) when the monitored settlement data reaches the critical settlement value, grouting the rigid sleeve valve pipe bundle in the grouting mileage, grouting in the order from short to long according to the length of the steel pipe in the rigid sleeve valve pipe bundle, using one rigid sleeve valve pipe each time and the other rigid sleeve valve pipes as standby, real-time monitoring the settlement data during the grouting process, and stopping grouting when the monitored settlement data reaches the requirement; and (7) after completing the grouting, continuing to monitor the change of the settlement data of the control settlement mileage, repeating step (6) when the monitored settlement data reaches the critical settlement value, and until the entire stratum of the control settlement mileage is completed.

[0009] Among them, the vertical radial rigid sleeve valve pipe bundle grouting control settlement method provided by the present application can meet the vast majority of underground chamber excavation control deformation engineering construction.

[0010] Optionally, the rigid sleeve valve pipe bundle in step (1) is processed by using a seamless steel pipe or a common steel pipe with a diameter of 15 mm, 20 mm, or 32 mm, etc.

[0011] Preferably, in step (1), the rigid sleeve valve pipe bundle contains 3-6 steel pipes.

[0012] Preferably, in step (1), the distance between the overflow holes is set as 100-500 mm.

[0013] Optionally, in step (1), the overflow hole of the rigid sleeve valve pipe can be selected to be pasted with a piece first and then installed with a stop valve sleeve or directly installed with a stop valve sleeve.

[0014] Optionally, in step (1), the steel pipes in the rigid sleeve valve pipe bundle are combined and fixed by welding or support binding.

[0015] Optionally, in step (2), the drilling method is set as air drilling, water drilling or spiral drilling.

[0016] Preferably, in step (2), the drilling machine can adapt to various angles and must be able to drill vertically upward, and the drilling diameter meets the installation requirements of the rigid sleeve valve pipe bundle.

[0017] Optionally, in step (2), after drilling to the set depth, washing or cleaning the hole is performed.

[0018] Preferably, the hole depth of the grouting control settlement hole is set to 2-10m, and the diameter of the grouting control settlement hole is set to 30-90mm. For example, a pipe bundle of 4 rigid sleeve valve pipes can be used, and the lengths of the rigid sleeve valve pipes are set to 2m, 4.5m, 7m, and 9.5m, respectively.

[0019] Optionally, in step (3), the end of the grouting pipe is sealed, and the length of the grouting pipe is set to 3-5cm from the bottom of the grouting control settlement hole.

[0020] Optionally, in step (3), the length of the exhaust pipe is set to be longer than the depth of the grouting control settlement hole.

[0021] Preferably, the diameters of the grouting pipe and the exhaust pipe are set to 8-20mm.

[0022] Optionally, in step (4), the casing material includes water, cement, bentonite, and water glass, and the ratio by weight of water, cement, bentonite, and water glass is: water 100 parts, cement 100-200 parts, bentonite 100-300 parts, and water glass 50-60 parts.

[0023] Optionally, in step (6), the length of each section of the grouting section is set to 0.5-2m, and the grouting pressure is set to 0.5-2.0MPa.

[0024] Optionally, in step (6), the grouting liquid is selected from cement-water glass double-liquid slurry with rapid setting and early strength, sulphoaluminate cement single-liquid slurry, or modified ordinary cement single-liquid slurry, wherein the initial setting time of the single-liquid slurry is set to 10-20 minutes, the final setting time is set to 30-60 minutes, and the initial setting time of the double-liquid slurry is set to 40-100 seconds.

[0025] Preferably, in step (7), the critical settlement value is the allowable settlement value determined according to the importance of the nearby buildings, and is set to 3-30mm.

[0026] Alternatively, the rigid sleeve valve pipe connector can be connected by threads or quick connectors.

[0027] The beneficial effects of the present application are: (1) not affecting the excavation progress, avoiding the construction safety risk and shutdown treatment risk after serious settlement, filling the blank of ineffective control of late deformation; (2) parallel construction or cross construction with excavation and support, which will not affect the normal construction process and can provide safety guarantee for normal construction; (3) fast construction and fast settlement control can be realized to effectively prevent settlement deformation; (4) low-pressure large-area grouting is adopted to realize settlement prevention, settlement compensation and even settlement lifting to ensure construction safety and structural safety; (5) the construction equipment is mature, the technology is reliable, the effect is remarkable, and the cost is low. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 A process schematic diagram of step (1) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0029] Figure 2A And Figure 2B A process schematic diagram of step (2) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0030] Figure 3 A process schematic diagram of step (3) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0031] Figure 4 A process schematic diagram of step (4) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0032] Figure 5 A process schematic diagram of step (5) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0033] Figure 6 A process schematic diagram of step (6) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown.

[0034] Figure 7 A process schematic diagram of step (7) of the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application is shown DETAILED DESCRIPTION

[0035] Next, the vertical radial rigid sleeve valve pipe bundle grouting settlement control method of the present application will be specifically described with reference to the drawings.

[0036] First, as Figure 1As shown, the rigid sleeve valve pipe bundle 1 is made in step 1. First, the length of the steel pipe is determined according to the distance between the orifice H and the hole bottom D, and three steel pipes G1, G2 and G3 are cut in order from short to long, with the length difference controlled at 3 meters. Overflow holes 2 are drilled on the steel pipes G1, G2 and G3, then the overflow holes 2 are pasted and the stop valve sleeves are installed, the front end of each steel pipe is processed into a sharp shape, and the other end, i.e. the grouting end, is processed into a thread connection. The processed steel pipes G1, G2 and G3 are firmly connected by welding or binding to form the rigid sleeve valve pipe bundle 1.

[0037] In this step, as another non-limiting embodiment, the number of steel pipes can be increased according to the grouting needs, such as 4, 5, etc.

[0038] Then, in step 2, as shown in Figure 2A and Figure 2B , taking tunnel excavation as an example, a grouting settlement control hole 4 is designed according to the pre-reinforcement contour line 3 of the settlement control section under the ground F, then the position of the grouting settlement control hole 4 is measured and marked at the initial support arch 7, and the hole center and cross line are marked with paint and the hole number is marked according to the design. Figure 2B As shown, a small crawler drill 5 or a pneumatic rock drill and other drilling equipment on the drill platform 8 is used to adjust the drill 5 at the hole position of the measured and marked grouting settlement control hole 4, adjust the drill rod 6 at the angle required by the design, and drill the hole under the action of the power head 9 using a suitable type of drill bit (not shown in the figure), then lengthen the drill rod 6 to drill to the designed hole depth of the hole bottom D, then wash or clean the hole to ensure that the installation depth of the rigid sleeve valve pipe bundle meets the design requirements, and then the drill rod 6 is disassembled after the washing or cleaning of the hole is completed.

[0039] Then, in step 3, the rigid sleeve valve pipe bundle 1 is installed using a drill or manually, as shown in Figure 3 Before installing the rigid sleeve valve pipe bundle 1, the grouting pipe 10 and the exhaust pipe 11 are first bound on the rigid sleeve valve pipe bundle 1, the end of the grouting pipe 10 is sealed with soft material and the length is set to be 3-5 cm away from the hole bottom D, the depth of the exhaust pipe 11 is slightly longer than the sealing length, then the gap at the orifice H is closed with cement and the rigid sleeve valve pipe bundle 1, the grouting pipe 10 and the exhaust pipe 11 are fixed.

[0040] Subsequently, in step 4, as shown in Figure 4 , after the sealing cement reaches the strength, the casing material is mixed using a mixing barrel 12, sent to a double-liquid grouting pump 14 through a grouting pipe 13, and injected into the hole through the grouting pipe 10 connected by a high-pressure grouting hose 15 using the double-liquid grouting pump 14. When grouting leaks from the exhaust pipe 11, the exhaust pipe 11 is closed and the casing material injection is stopped, i.e. the casing material injection is completed. The casing material must be injected immediately after all the holes are completed.

[0041] In this step, as a non-limiting embodiment, the casing material includes: water, cement, bentonite and water glass, wherein the proportion of water, cement, bentonite and water glass by weight is: 100 parts water, 100-200 parts cement, 100-300 parts bentonite and 50-60 parts water glass.

[0042] Then, in step 5, as Figure 5 As shown, at the control settlement mileage, settlement observation point 16 is installed on the ground F or on the building that needs to be monitored, and settlement observation point 16 and convergence observation point 17 are installed inside the tunnel. Then, the monitoring instrument 18 is used to record the initial data and monitor the changes in settlement data in real time.

[0043] In step 6, as Figure 6 As shown, according to the monitoring data, if the settlement value reaches the value that needs to be controlled by grouting, the dual-liquid grouting pump 14 is connected to the rigid sleeve valve bundle 1 within the settlement range. The grouting sequence is from shortest to longest, that is, starting from the first section G1 and proceeding in sequence. Only one pipe is used for each grouting. The grouting material is a fast-setting environmentally friendly material to achieve the purpose of quickly controlling the settlement. During the grouting process, the monitoring instrument 18 should be used to monitor the settlement data in real time. When the control requirements are met, the grouting should be stopped. During the grouting process, the changes in settlement data and grouting pressure should be observed in real time. If any abnormality occurs, the grouting should be stopped immediately and construction can only continue after the problem is resolved.

[0044] In one non-limiting embodiment, the segment length of the grouting section is set to 0.5–2 meters, and the grouting pressure is set to 0.5–2.0 MPa. The grouting fluid used is a cement-water glass two-component grout, a sulfoaluminate cement single-component grout, or a modified ordinary cement single-component grout, all of which have rapid setting and early strength characteristics. The initial setting time of the single-component grout is set to 10–20 minutes, and the final setting time is set to 30–60 minutes. The initial setting time of the two-component grout is set to 40–100 seconds.

[0045] Finally, in step 7, as Figure 7 As shown, after grouting is completed, monitoring instrument 18 is used to continue monitoring the grouting control settlement area. As the stratum stress changes, the settlement area changes accordingly. When the monitored settlement or convergence data reaches the limit, step 6 is repeated. This process is repeated to effectively control settlement and other deformations, and to ensure the safety of the surrounding strata and structures during stable excavation.

[0046] The following examples illustrate the application of the construction method of the present invention in engineering.

[0047] This project is Contract Section 10 of the civil construction of Beijing Metro Line 12, which includes one station and one section: Anzhenqiao Station and the section between Anhuaqiao Station and Anzhenqiao Station. Anzhenqiao Station is a cut-and-cover, double-layered, separated island platform station with a single-span, column-free structure, constructed using the "tunnel-pile method".

[0048] The station construction involved four construction shafts for the main structure: Shaft No. 1, which also served as the No. 1 ventilation shaft, was located in Yongxi Park; Shaft No. 2 was located in the green space southwest of Beijing Rural Commercial Bank; Shaft No. 3 was located in the green space between Anzhen Building and Global Trade Center; and Shaft No. 4 was located west of Anzhen Building.

[0049] The No. 1 ventilation duct of Anzhen Bridge Station passes through the western bridge pile of Anzhen Bridge. During the excavation, it caused settlement of the western abutment of Anzhen Bridge. The maximum settlement was 39.43 mm on July 6. Monitoring data shows that the abutment is still settling, directly affecting the safety of the Third Ring Road. The surface soil cover at this location is 19.3 m, which is relatively shallow, and the requirements for settlement control are extremely strict.

[0050] After adopting the vertical radial rigid sleeve valve grouting method for controlling settlement of the present invention, the stratum was effectively filled and reinforced, and the settlement rate of the bridge abutment, surrounding buildings and the Third Ring Road was effectively controlled, greatly suppressing settlement deformation and never allowing the settlement to reach the warning value, thus ensuring construction safety.

[0051] Although preferred embodiments of the invention have been described in detail herein, it should be understood that the invention is not limited to the specific structures and steps described and shown herein, and other variations and modifications can be made by those skilled in the art without departing from the spirit and scope of the invention.

Claims

1. A method for controlling settlement by grouting a vertically radial rigid sleeve valve tube bundle, comprising: (1) Cut at least three steel pipes with successively increasing lengths, with a length difference of 2 to 5 meters. Mark the position of the overflow hole on each steel pipe and drill the overflow hole. Install a stop valve sleeve at each overflow hole. Process one end of each steel pipe into a pointed end and the other end into a threaded end to form a rigid sleeve valve pipe. Combine and fix at least three rigid sleeve valve pipes to form a rigid sleeve valve pipe bundle. (2) Mark the positions of several grouting control settlement holes in the initial support arch of the control settlement mileage, and drill holes at each of the grouting control settlement holes at an angle perpendicular to the initial support arch to a set depth. (3) Bind the grouting pipe and the exhaust pipe to the rigid sleeve valve tube bundle, and then send the rigid sleeve valve tube bundle, the grouting pipe and the exhaust pipe into the grouting control settlement hole. Then seal the grouting control settlement hole and fix the rigid sleeve valve tube bundle, the grouting pipe and the exhaust pipe. (4) After the sealing material reaches the required strength, the casing material is injected through the grouting pipe. When the vent pipe leaks grout, the vent pipe is closed to complete the injection of the casing material. (5) After the support is completed, install settlement observation points and convergence observation points at the set locations, record the initial data, and monitor the changes in settlement data of the control settlement mileage in real time. (6) When the monitored settlement data reaches the critical settlement value, grouting is performed on the rigid sleeve valve tube bundle within the grouting mileage. Grouting is carried out in ascending order of the length of the steel pipes in the rigid sleeve valve tube bundle, using one rigid sleeve valve tube at a time, with the others as spares. The settlement data is monitored in real time during the grouting process, and grouting is stopped when the monitored settlement data reaches the required level; and (7) After grouting is completed, continue to monitor the changes in settlement data of the controlled settlement mileage. When the monitored settlement data reaches the critical settlement value, repeat step (6) until all strata of the controlled settlement mileage are completed.

2. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 1, characterized in that, In step (1), the diameter of the steel pipe is set to 15 mm, 20 mm, or 32 mm.

3. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 2, characterized in that, In step (1), a patch is applied to each of the overflow holes before the grout stop valve sleeve is installed.

4. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 3, characterized in that, In step (1), the steel pipes in the rigid sleeve valve bundle are fixed by welding or by binding with brackets.

5. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 4, characterized in that, In step (2), the drilling method is set to pneumatic drilling, water drilling, or spiral drilling.

6. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 5, characterized in that, In step (2), after drilling to the set depth, the hole is washed or cleaned.

7. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 6, characterized in that, In step (3), the end of the grouting pipe is sealed, and the length of the grouting pipe is set so that its bottom end is 3 to 5 centimeters away from the bottom of the grouting control settlement hole.

8. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 7, characterized in that, In step (3), the length of the exhaust pipe is set to be longer than the depth of the grouting control settling hole.

9. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 6, characterized in that, In step (4), the shell material includes: water, cement, bentonite and water glass, wherein the proportion of water, cement, bentonite and water glass by weight is: 100 parts water, 100-200 parts cement, 100-300 parts bentonite and 50-60 parts water glass.

10. The method for controlling settlement by grouting vertical radial rigid sleeve valve tube bundle as described in claim 9, characterized in that, In step (6), the segment length of the grouting section is set to 0.5 to 2 meters, and the grouting pressure is set to 0.5 to 2.0 MPa.

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