Prefabricated composite reinforced structure serving as a dewatering grouting channel and construction method

Abstract

The present invention discloses a prefabricated composite reinforced structure that also serves as a dewatering and grouting channel, and its construction method. The composite reinforced structure comprises an inner permeable pipe, thick-walled permeable pipe material, and a filter layer, arranged sequentially from the inside out. Construction involves the following steps: prefabricating the composite reinforced structure, sinking piles, dewatering, grouting, installing cast-in-place prefabricated pile caps, and laying a cushion layer and flooring. The present invention ensures the strength of the composite reinforced structure, offers the advantages of rapid construction, cost savings, effective improvement of foundation bearing capacity, and deformation control. Furthermore, the dewatering process can be automated during construction through automatic control.

Description

Technical Field

[0001] The invention relates to the technical field of foundation treatment, in particular to a prefabricated composite reinforced body structure serving as a dewatering grouting channel and a construction method thereof. Background Art

[0002] When constructing buildings on soft soils such as soft soil and fill, it is necessary to ensure the stability of the foundation, improve the strength of the soft foundation, reduce the compressibility of the soft soil, and reduce the settlement and uneven settlement of the foundation. Reinforcement methods such as drainage consolidation, vibration compaction, and reinforced soil are often used. Various commonly used foundation treatment solutions are used alone and have some shortcomings. For example, lime piles, rotary jet piles, and pipe piles are expensive and relatively difficult to control in quality; vacuum preloading and surcharge preloading methods have relatively long construction periods, slow foundation consolidation, or the need to set up additional vertical drainage channels.

[0003] In soft soils such as soft soil and fill, the excavation of deep foundation pits causes certain deformation of the surrounding soil layers, which may have adverse effects and hazards on the surrounding environment. Grouting, rotary grouting, mixing piles or other methods are often used to add a certain amount of curing agent to the foundation or consolidate the soil. However, there are problems such as insufficient reinforcement strength or relatively long construction period.

[0004] In summary, when reinforcing foundations and foundation pits in soft soil, fill and other weak foundations, the reinforced body must have the advantages of drainage, reinforcement, fast construction and low cost. Summary of the Invention

[0005] The purpose of the present invention is to provide a prefabricated composite reinforced body structure which also serves as a dewatering grouting channel and a construction method thereof, so as to solve the problems existing in the prior art.

[0006] The object of the present invention is achieved as follows: a prefabricated composite reinforced structure serving as a dewatering grouting channel, comprising:

[0007] The inner permeable pipe is configured as a segmented splicing structure;

[0008] The thick-walled water-permeable pipe wrapped around the outer wall of the inner water-permeable pipe is configured as a segmented splicing structure, and its wall thickness is greater than that of the inner water-permeable pipe;

[0009] The filter layer wraps the outer wall and bottom end of the thick-walled permeable pipe.

[0010] Furthermore, a finished bottom cover is packaged at the bottom of the inner water-permeable pipe.

[0011] Furthermore, a plurality of water-permeable holes are provided on the wall of the inner water-permeable pipe.

[0012] Furthermore, the inner water-permeable pipe is provided with a plurality of connectors, and any two adjacent unit sections of the inner water-permeable pipe are sealed and spliced ​​by the connectors.

[0013] Furthermore, the thick-walled water-permeable pipe is provided with a plurality of connectors, and any two adjacent unit sections of the thick-walled water-permeable pipe are sealed and spliced ​​by the connectors.

[0014] As another aspect of the present invention, a construction method for a prefabricated composite reinforcement body that also serves as a dewatering grouting channel is provided, comprising the following steps:

[0015] S1, prefabricated composite reinforced structure;

[0016] S2. performing pile sinking operation on the prefabricated composite reinforced structure;

[0017] S3, repeating steps S1-S2 to obtain a plurality of composite reinforced structures and performing pile driving operations on all of them;

[0018] S4. Connecting the branch pipes one by one to the composite reinforced structures, and then connecting all the branch pipes in parallel to a main pipe to form a parallel pipeline, and then connecting the main pipe to a pumping device, and starting the pumping device to reduce water;

[0019] S5. After the precipitation is completed, the pumping equipment is replaced with grouting equipment to perform grouting or filling material operations.

[0020] Preferably, in step S2, a steel casing is provided, the steel casing is sleeved over the entire composite reinforced structure, and the bottom end of the steel casing is sealed with a sealing plate. After the piles are sunk to the designed elevation, the steel casing is pulled out and recovered.

[0021] Preferably, in step S4, the inner water-permeable pipe is connected to the branch pipe via a reinforced reducer.

[0022] Preferably, in step S4, automatic control valves are provided on the main pipe and / or all branch pipes, monitoring equipment for monitoring flow is provided on the main pipe and / or all branch pipes, and all automatic control valves and monitoring equipment are connected by an electronic control system.

[0023] Preferably, step S6 is also included. When step S6 is being carried out, cast-in-situ prefabricated pile caps are installed to seal all composite reinforced body structures one by one; in step S6, the cast-in-situ prefabricated pile caps are cast through pipe templates, and the head of the composite reinforced body structure is connected to the cast-in-situ prefabricated pile cap by inserting vertical reinforcing members, or holes are reserved in the cast-in-situ prefabricated pile caps, and the inner permeable pipes are higher than the thick-walled permeable pipes, and are upwardly embedded in the reserved holes of the cast-in-situ prefabricated pile caps to realize the connection operation between the head of the composite reinforced body structure and the cast-in-situ prefabricated pile cap, and the setting material is used to form the two into an integrated structure; in step S2, the composite reinforced body structure can be arranged vertically or obliquely.

[0024] The beneficial effects of the present invention are:

[0025] The prefabricated composite reinforcement structure can improve the permeability of the pile body while ensuring the strength of the pile body, prevent soil particle blockage, and improve drainage consolidation efficiency; the thick-walled permeable pipe serves as a drainage channel and a grouting reinforcement, and the smaller diameter inner permeable pipe serves as a reinforcement, a drainage channel, and a grouting channel, integrating drainage reinforcement, grouting reinforcement, and composite foundation reinforcement. It has the advantages of fast construction, cost saving, effective improvement of foundation bearing capacity, and control of deformation; it can also be used for foundation pit reinforcement, quickly controlling the deformation of the soil inside and outside the pit, and the reinforcement outside the pit plays a role in water stopping, Reduce the effect of active earth pressure on the retaining structure; pit reinforcement improves soil strength and lateral resistance, reduces displacement of retaining structure, prevents uplift and damage of pit bottom soil, and protects buildings and underground pipelines around the foundation pit; the dewatering pipeline system adopts a parallel setting to reduce the number of pumping equipment (pumps); the reinforced reducer can be used for dewatering operations and grouting operations at the same time to save materials; the control system composed of monitoring equipment, automatic control valves, and electronic control systems realizes automatic control of the dewatering process, so that the dewatering benefits are maximized. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of a prefabricated composite reinforced structure.

[0027] Figure 2 It is a schematic diagram of pile driving with outer steel casing.

[0028] Figure 3 Pull out the steel casing and repeat Figure 1-2 Schematic diagram of the steps shown.

[0029] Figure 4 This is a schematic diagram of automated precipitation control.

[0030] Figure 5 It is a schematic diagram of grouting.

[0031] Figure 6 It is a schematic diagram of pile head excavation and installation of cast-in-place prefabricated pile cap.

[0032] Figure 7 It is a schematic diagram of laying the mattress layer and pouring the floor.

[0033] Figure 8 It is a schematic diagram of the use status of the connector.

[0034] Figure 9 This is another schematic diagram of the connector in use.

[0035] Figure 10 It is a schematic diagram of cast-in-place precast pile cap.

[0036] In the figure, 1-inner permeable pipe, 2-thick-wall permeable pipe, 3-filtration layer, 4-connecting parts, 5-permeable holes, 6-finished bottom cover, 7-steel casing, 8-sealing plate, 9-reinforced reducer, 10-branch pipe, 11-main pipe, 12-automatic control valve, 13-monitoring equipment, 14-pumping equipment, 15-grouting equipment, 16-cast-in-situ prefabricated pile cap, 17-reinforced components, 18-cushion layer, 19-floor, 20-waterstop. DETAILED DESCRIPTION

[0037] The following is combined with Figure 1-10 The present invention is further described with reference to the accompanying drawings and specific examples.

[0038] like Figure 1 As shown, a prefabricated composite reinforced structure serving as a dewatering grouting channel includes:

[0039] The inner water-permeable pipe 1 is configured as a segmented splicing structure. A finished bottom cover 6 is encapsulated at the bottom of the inner water-permeable pipe 1. A plurality of water-permeable holes 5 are opened on the pipe wall of the inner water-permeable pipe 1. The inner water-permeable pipe 1 can be made of a rigid material such as a steel pipe, high-strength PVC / PE, and has the functions of reinforcement, precipitation channel, and grouting channel.

[0040] The thick-walled permeable pipe 2 wrapped around the outer wall of the inner permeable pipe 1 is configured as a segmented splicing structure, and its wall thickness is greater than that of the inner permeable pipe 1. The thick-walled permeable pipe 2 includes permeable pipes of a certain thickness such as drainage blind ditches and sandless pipe wells, and serves as both a drainage channel and a reinforcement body formed by grouting reinforcement. The inner diameter of the thick-walled permeable pipe 2 is greater than the outer diameter of the inner permeable pipe 1, and a certain setting gap can be formed;

[0041] The filter layer 3 wraps the outer wall and bottom end of the thick-walled permeable pipe 2. The filter layer 3 is made of a material with filtering function such as geotextile, which allows water and slurry to pass through but prevents soil particles from entering the thick-walled permeable pipe 2 in reverse.

[0042] The inner diameter of the finished bottom cover 6 is greater than or equal to the outer diameter of the inner water-permeable pipe 1 , which protects the filter layer 3 during the pile sinking process and prevents the inner water-permeable pipe 1 from damaging the filter layer 3 during the sedimentation process.

[0043] Among them, Figure 8 、 9 As shown, the inner water-permeable pipe 1 is equipped with a plurality of connectors 4, and any two adjacent unit sections of the inner water-permeable pipe 1 are sealed and spliced ​​by the connectors 4; the thick-walled water-permeable pipe 2 is equipped with a plurality of connectors 4, and any two adjacent unit sections of the thick-walled water-permeable pipe 2 are sealed and spliced ​​by the connectors 4; the connectors 4 can be fixed by various means such as gluing and screws to achieve the purpose of effectively connecting the inner water-permeable pipe 1 and the thick-walled water-permeable pipe 2; the structure of the connector 4 can be a connecting sleeve structure, which can simultaneously fix and sleeve any two adjacent pipe sections of the inner water-permeable pipe 1 and the thick-walled water-permeable pipe 2; as shown Figure 9As shown, in order to enhance the connection strength, a limiting protrusion can be provided on the inner wall of the connector 4 and inserted into any two adjacent pipe sections of the thick-walled permeable pipe 2; Figure 8 As shown, a limiting flange can be provided on the inner wall of the connector 4 so that any two adjacent pipe sections of the inner water-permeable pipe 1 relatively contact the two ends of the limiting flange to improve the docking accuracy of any two adjacent pipe sections of the inner water-permeable pipe 1; the structural form of the above-mentioned connector 4 includes but is not limited to the scheme proposed in this embodiment, and can be flexibly set according to project requirements.

[0044] Reference Figure 1-7 As shown, the construction method of this embodiment includes the following steps:

[0045] S1, prefabricated composite reinforced structure;

[0046] S2. Cover the entire composite reinforced structure with a steel casing 7. The composite reinforced structure can be arranged vertically or obliquely, and the bottom end of the steel casing 7 is sealed with a sealing plate 8 to carry out the pile sinking operation. The inner diameter of the steel casing 7 is slightly larger than the outer diameter of the composite reinforced structure. The pile sinking can be carried out by drilling, vibration or static pressure. After the pile sinking is completed, the steel casing 7 is pulled out and recovered;

[0047] S3, repeating steps S1-S2 to obtain a plurality of composite reinforced structures and sinking piles;

[0048] S4. Connect several branch pipes 10 one by one to several composite reinforced structures, then connect all branch pipes 10 in parallel to a main pipe 11 to form a parallel pipeline, then connect the main pipe 11 to a pumping device 14, and start the pumping device 14 to perform precipitation;

[0049] S5. After the precipitation is completed, the pumping equipment 14 is replaced with the grouting equipment 15 to perform grouting or filling material operation;

[0050] S6. Install cast-in-situ prefabricated pile caps 16 to enclose all composite reinforcement structures one by one;

[0051] S7. According to the project requirements, after the cast-in-situ prefabricated pile cap 16 reaches the designed strength, the cushion layer 18 and the floor 19 are laid in sequence.

[0052] Among them, in the above steps S1-S2, the pile sinking method is not limited to the static pressure pile sinking method using the steel casing 7, other pile sinking methods can also be used. For the present invention, no matter which pile sinking method is replaced, it falls within the protection scope of the present invention.

[0053] In step S4, if vacuum dewatering is used, a water stop 20 must be installed on the top of the composite reinforced structure. The water stop 20 is configured as a water stop layer or sealing plate. The inner water permeable pipe 1 is connected to the branch pipe 10 via a reinforced reducer 9. The reinforced reducer 9 is used to connect the inner water permeable pipe 1 and the branch pipe 10 for pumping water. It must also meet the grouting pressure requirements and can be reused for grouting after dewatering. The reinforced reducer 9 needs to be able to be used for both pumping and grouting operations.

[0054] During pumping, groundwater passes through the filter layer 3, the thick-walled permeable pipe 2, and the permeable holes 5 in turn into the lumen of the inner permeable pipe 1 and is discharged; during grouting, the slurry passes through the permeable holes 5 in turn into the thick-walled permeable pipe 2 and the surrounding soil to form a reinforcement body.

[0055] In step S4, in order to realize automatic control of the precipitation process, automatic control valves 12 are set on both sides of the connection point between the main pipe 11 and the pumping equipment 14, and a monitoring device 13 for monitoring the flow is set on each automatic control valve 12. All automatic control valves 12 and monitoring devices 13 are connected by an electronic control system. If the flow data fed back by one of the monitoring devices 13 is less than the monitoring index flow, the automatic control valve 12 of the corresponding line is closed; if the flow data fed back by the monitoring device 13 is greater than or equal to the monitoring index flow, the automatic control valve 12 of the corresponding line is kept in the open state to continue precipitation.

[0056] In step S6, refer to Figure 6 、 10 The cast-in-situ prefabricated pile cap 16 is cast through a pipe template, and the composite reinforcement body structure head is connected to the cast-in-situ prefabricated pile cap 16 by inserting a vertical reinforcement member 17, or the cast-in-situ prefabricated pile cap 16 has a reserved hole, and the inner permeable pipe 1 is higher than the thick-walled permeable pipe 2 and upwardly embedded in the reserved hole of the cast-in-situ prefabricated pile cap 16 to achieve the connection operation between the composite reinforcement body structure head and the cast-in-situ prefabricated pile cap 16, and the two are formed into an integrated structure by using unhardened slurry or cement slurry and other setting materials.

[0057] The above are preferred embodiments of the present invention. Those skilled in the art may make various changes or improvements based on the above. Without departing from the overall concept of the present invention, these changes or improvements should fall within the scope of protection required by the present invention.

Claims

1. A construction method for a prefabricated composite reinforcement body that also serves as a precipitation grouting channel, characterized in that: The steps include: S1, a prefabricated composite reinforced solid structure, the composite reinforced solid structure comprising: an inner water-permeable pipe (1), which is configured as a segmented splicing structure; a thick-walled water-permeable pipe (2) wrapped around the outer wall of the inner water-permeable pipe (1), which is configured as a segmented splicing structure and has a wall thickness greater than that of the inner water-permeable pipe (1); and a filter layer (3), which wraps around the outer wall and bottom end of the thick-walled water-permeable pipe (2); S2. performing pile sinking operation on the prefabricated composite reinforced structure; S3, repeating steps S1-S2 to obtain a plurality of composite reinforced structures and performing pile driving operations on all of them; S4, connecting the plurality of branch pipes (10) one by one to the plurality of composite reinforced structures, then connecting all the branch pipes (10) in parallel to a main pipe (11), thereby forming a parallel pipeline, then connecting the main pipe (11) to a pumping device (14), and starting the pumping device (14) to perform precipitation; S5. After the precipitation is completed, the pumping equipment (14) is replaced with the grouting equipment (15) to perform grouting or filling material operation; In step S4, automatic control valves (12) are provided on the main pipe (11) and / or all branch pipes (10), monitoring devices (13) for monitoring flow rates are provided on the main pipe (11) and / or all branch pipes (10), and all automatic control valves (12) and monitoring devices (13) are connected by an electronic control system; If the flow data fed back by one of the monitoring devices (13) is less than the monitoring index flow, the automatic control valve (12) of the corresponding line is closed; if the flow data fed back by the monitoring device (13) is greater than or equal to the monitoring index flow, the automatic control valve (12) of the corresponding line continues to be kept in an open state.

2. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: A finished bottom cover (6) is packaged at the bottom of the inner water-permeable pipe (1).

3. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: A plurality of water-permeable holes (5) are provided on the wall of the inner water-permeable pipe (1).

4. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: The inner water-permeable pipe (1) is equipped with a plurality of connecting pieces (4), and any two adjacent unit sections of the inner water-permeable pipe (1) are sealed and spliced ​​by the connecting pieces (4).

5. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: The thick-walled water-permeable pipe (2) is provided with a plurality of connectors (4), and any two adjacent unit sections of the thick-walled water-permeable pipe (2) are sealed and spliced ​​by the connectors (4).

6. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: In step S2, a steel casing (7) is provided, the steel casing (7) is sheathed around the entire composite reinforced structure, and the bottom end of the steel casing (7) is sealed with a sealing plate (8). After the pile is sunk to the designed elevation, the steel casing (7) is pulled out and recovered.

7. The construction method of a prefabricated composite reinforcement body serving as a dewatering grouting channel according to claim 1, characterized in that: In step S4, the inner permeable pipe (1) is connected to the branch pipe (10) via the reinforced reducer (9).

8. The construction method of a prefabricated composite reinforcement body also serving as a dewatering grouting channel according to claim 1, characterized in that: The method further includes step S6, during which the cast-in-situ prefabricated pile caps (16) are installed to seal all the composite reinforcement structures one by one. In step S6, the cast-in-situ prefabricated pile caps (16) are cast through a pipe template, and the head of the composite reinforcement structure is connected to the cast-in-situ prefabricated pile caps (16) by inserting a vertical reinforcement member (17), or a hole is reserved in the cast-in-situ prefabricated pile cap (16), and the inner permeable pipe (1) is higher than the thick-walled permeable pipe (2) and is upwardly embedded in the reserved hole of the cast-in-situ prefabricated pile cap (16), thereby realizing the connection operation between the head of the composite reinforcement structure and the cast-in-situ prefabricated pile cap (16), and the two are formed into an integrated structure by using a setting material. In step S2, the composite reinforcement structure is arranged vertically or obliquely.

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