TWI550162B - Construction method of underground retaining wall - Google Patents

Description

Underground retaining wall construction method

The present invention relates to a method for constructing an underground retaining wall, and more particularly to a method for constructing an underground retaining wall capable of preventing collapse of a stratum. The wall structure has a hollow rectangular shape, and uses the hollow space condition to carry out the three-stage goal of construction machinery erection and recovery, wall construction and settlement, and backfill grouting into a solid retaining wall.

The basement excavation of high-rise buildings usually adopts continuous wall as the retaining structure. The existing continuous wall construction method is to prepare the grounding, lofting and positioning, setting up the stability liquid pool, sinking mud and other supporting equipment, and then accurately construct the guiding ditch. .

After the preparation work is completed, according to the geological conditions, construction requirements, environmental conditions and the number of projects, etc., the appropriate excavation machinery is selected, and the excavation work of each male and female unit trench is carried out one by one, and the underground continuous wall trench is excavated by using the stability liquid. To maintain the stability of the trench during construction, the stability liquid is mixed with other chemical additives by bentonite, and the mixture of each weight percentage and water is mixed, and a plastic fluid with special fluidity causes the mud wall of the groove wall to prevent mud The wall surface is peeled off, and the stability liquid flow or the groundwater intrusion in the groove is prevented, and the effect of preventing the wall of the groove from collapsing is achieved.

After the excavator has been excavated to a predetermined design depth, the excavator is taken out and the steel cage and the special pipe are suspended to carry out concrete grouting.

The concrete filling method of the continuous wall is specific, and the special pipe is used to penetrate the bottom of the groove, and the concrete is pushed upward from the bottom, and the partitioning liquid in the groove is successively squeezed to take the volume. Complete the continuous wall construction of each unit in the underground. The tranquilizer is reused after recycling.

In the above, after the completion of the operation of one unit of continuous wall, it takes time to maintain the predetermined structural strength, so that the adjacent unit cannot be connected to the vicinity, so the continuous wall of each unit adopts the method of jumper construction.

The above continuous wall construction method will cause the following problems:

1. High cost: The function and characteristics of the stability liquid are used in the continuous wall construction method to maintain the stability of the excavation trench. Among them, the stability of the stability liquid is expensive and requires regular quality inspection, which is costly and can be recycled and reused. The performance of recycled stabilizers still needs to meet strict quality specifications, and recycling requires additional processing costs. The stabilizers that do not meet the quality specifications cannot be used continuously and are forced to be recycled. Therefore, the use of stabilizers has a high cost.

2. Not environmentally friendly: The stable liquid with serious pollution cannot continue to be recycled, and its waste recycling needs special treatment, which causes environmental problems.

3. Prone to catastrophic changes: Due to the high price of the stabilizer, the contractor can save the amount of its use in order to save costs, or use inferior products, or even use clay as the use, can not effectively play the normal function of the stabilizer. So that the trench excavation stage: the disaster causing the trench collapse, in the continuous wall watering concrete stage: the inferior stability liquid will cause the wall unit to generate the honeycomb structure and reduce the structural strength of the wall unit and the watertightness of the construction joint, and then When the deep excavation stage of the basement is affected: the incidence of catastrophes such as seepage of the wall and collapse of the ground outside the excavation area.

4. Time consuming: After the continuous wall construction method is completely excavated to a certain depth, after confirming the verticality of the wall and the quality of the stability liquid, the steel cage and the special pipe will be suspended, and the concrete will be re-infused to form each wall unit. . Moreover, the wall unit needs time to be maintained to a certain structural strength, so that the adjacent unit can be applied. Therefore, it takes a long time to complete one unit continuous wall. In addition, the male and female units must be jumped and excavated, and the working hours cannot be shortened.

The main purpose of this creation is to provide a continuous wall construction method, which aims to improve the high cost, safety and safety problems, environmental safety problems, disasters and time-consuming problems caused by the current continuous wall construction method.

In order to achieve the purpose of the previous disclosure, the construction method of the underground retaining wall of the present invention includes: preparing the work, finishing the construction site and setting up the supporting equipment such as the grit chamber and the working room, and then constructing the guiding groove after the positioning and positioning; The casting caisson seat is placed flat in the preset wall unit guide groove, and an excavating device, an extracting device and a water jet device are arranged in the caulking box seat. And injecting isolation liquid between the caisson and the guide groove, and injecting water into the sinking box seat, keeping the liquid level of the water in the sinking box seat more than 1 meter above the ground elevation, and erecting in the sinking box seat Frame, power line and hydraulic jack for resisting; wall making step, setting template device at the upper end of the wall of the caulking box seat, continuing the steel bar to the reserved rib of the sinking box seat, and the inner mold of the template device, The outer molds are respectively located on both sides of the steel bar and form a pouring space, and the concrete is poured into the pouring space. After the concrete is first solidified to a certain extent, the inner mold and the outer mold are lifted up together by the hydraulic system, and the empty space is poured again. Mixed Condensing the soil between the inner mold and the outer mold and waiting for the initial solidification of the concrete, and pressing the frame with the hydraulic jack, repeatedly performing the action of hydraulically lifting the inner mold, the outer mold, and pouring and solidifying to form each unit. Wall; excavation step, excavation device for excavation, and then the soil is extracted by the extraction device, the sinking box seat and the wall raft are set down, and the partitioning liquid is injected between the wall and the guiding groove, and the water is injected into the wall. Keep the liquid level of the water more than 1 meter above the ground elevation; after the wall is settled to the depth of the stage, continue to make the wall with the template equipment, continue the frame, the hydraulic jack, the mud pipe and the power line before proceeding The excavation step is repeated until the total length of the wall and the sinking box seat reaches the preset depth of the underground retaining wall; after the disassembly operation, the template device is first disassembled, and then the extracting device, the frame, the hydraulic jack, the excavating device, etc. All the equipments are hoisted and removed from the caisson seat in sequence, and the hollow section of the wall is backfilled and grouted simultaneously to complete the underground retaining wall of the solid section; the finishing step is on the wall of the underground retaining wall The body unit is finished finishing.

According to the above, the underground retaining wall construction method is in the wall making step, the wall made by the template device, and there is no broken hole honeycomb inferior concrete, which can prevent groundwater leakage and has sufficient structural strength to prevent Disasters such as trench collapse and ground collapse have achieved the goal of disaster prevention and improvement of work safety. And the wall structure has been formed to prevent soil/water pressure and reduce the amount of stabilizer solution used, thereby saving the cost of purchase, recovery and monitoring of the stabilizer solution, and being more environmentally friendly and improving the environmental safety problem. Repeated wall production and excavation can shorten working hours and can be based on groundwater and geological conditions. The distance between the inner mold and the outer mold of the template device is adjusted, the thickness of the wall at each stage is adjusted, and the caulking box seat and the excavating device of the appropriate size are selected, and the underground retaining wall of large size can be applied at one time. In addition, because the wall has a certain structural strength, the adjacent wall unit can simultaneously perform the installation work, the wall making step and the excavation, and the extraction step, thereby shortening the working hours.

10‧‧‧預鑄箱箱座

11‧‧‧

12‧‧‧ feet

13‧‧‧Steel toe

14‧‧‧ convex

15‧‧‧ Reserved space

20‧‧‧Excavating device

30‧‧‧ extraction device

40‧‧‧Template equipment

41‧‧‧Inner model

42‧‧‧External model

50‧‧‧ wall

60‧‧‧ Guide groove

70‧‧‧Hydraulic jack

Fig. 1 is a schematic view showing the construction of a guide groove according to a preferred embodiment of the method for constructing an underground retaining wall.

Fig. 2 is a schematic view showing a hanging box seat of a preferred embodiment of the method for constructing an underground retaining wall.

Fig. 3 is a schematic view showing the installation of an excavating device and an extracting device on a caulking box seat according to a preferred embodiment of the method for constructing an underground retaining wall.

FIG. 4 is a schematic view showing a template device disposed at an upper end of a sump box seat according to a preferred embodiment of the method for constructing a subterranean retaining wall.

Fig. 5 is a schematic view showing the steps of fabricating a wall according to a preferred embodiment of the method for constructing an underground retaining wall.

Fig. 6 is a schematic view showing the movement of the inner and outer molds in the wall forming step of a preferred embodiment of the method for constructing an underground retaining wall.

Fig. 7 is a schematic view showing the excavation steps of a preferred embodiment of the method for constructing an underground retaining wall.

The construction method of the underground retaining wall of the present invention includes preparation work, installation work, wall making step, excavation step, repeated application to stage depth, disassembly work and finishing finishing step.

In the preparation work, the construction site is arranged and the supporting equipment such as the grit chamber and the working room are set up, and then the positioning groove 60 is accurately positioned and set (as shown in Fig. 1), wherein the working room can be placed with machinery, air compressor, etc. .

Referring to FIG. 2 and FIG. 3, in the installation work, the caisson box seat 10 is placed flat in the guide groove at the wall unit of the preset underground retaining wall, between the sinker box seat 10 and the guide groove 60. There is a gap, and the excavating device 20, the extracting device 30 and the water jet device are installed in the caisson box seat 10, and the partitioning liquid is injected between the caisson box seat 10 and the guiding groove 60, and the sinking box seat 10 is filled with water, and The height of the water surface in the tamping tank seat 10 is maintained more than 1 metre above the ground elevation, and the frame and the hydraulic jack 70 are erected in the tamping tank seat 10 to maintain the frame vertical stability.

The sump box 10 includes a body 11 , and the base 11 is provided with a tapered seat 12 . The foot 12 is covered with a steel toe 13 for increasing the lower cutting force to facilitate the sluice box seat. 10 under the cut movement.

The seat body 11 is provided with a convex portion 14 above, and the outer periphery of the convex portion 14 forms a reserved space 15 to inject a spacer liquid to reduce the friction between the tamping box seat 10 and the soil wall.

Referring to FIG. 4 to FIG. 7 , a stencil apparatus 40 is disposed on the upper end of the wall of the sluice box base 10 , and the stencil apparatus 40 is used for wall forming on the convex portion 14 of the sump box seat 10 , and the reinforcing bar is first connected to the rafter. The caisson seat is reserved for the ribs.

Formwork devices such as the inner mold 41, the outer mold 42, and the yoke leg of the stencil apparatus 40 are respectively located on both sides of the steel bar and form a pouring space for pouring concrete into the pouring space.

After the initial setting of the concrete, the hydraulic system is opened and the screw is used. Pressing the force downwards pulls the inner mold 41 and the outer mold 42 upward, and presses the frame with a hydraulic jack.

The concrete is poured again into the space of the inner mold 41 and the outer mold 42 and waits for the initial solidification of the concrete, and the action of pulling the inner mold 41 and the outer mold 42 with casting and solidification is repeated to form a part of the wall 50 of the wall unit.

The oil pressure jack 70 top wall 50 is arranged one by one to maintain the vertical stability of the frame and to enhance the wall stiffness when the wall is settled to counter the lateral earth pressure.

After a part of the wall 50 is formed, the excavation step is carried out. Referring to FIG. 7, the excavating device 20 of the caisson box 10 performs excavation, and the extracting device 30 extracts the soil layer excavated by the excavating device 20, and simultaneously on the wall. The partitioning liquid is injected between the body 50 and the guide groove 60, and water is injected into the wall 50 to maintain the liquid level of the water more than 1 meter above the ground elevation.

The sinker 10 is subjected to its own weight, the weight of the wall 50, the weight of the frame and the water, can be smoothly lowered, and the excavating device 20 continues to excavate until a part of the wall 50 produced in the previous wall making step has been lowered. At the predetermined depth, the excavation is stopped.

The oil pressure jack 70 is supported by the stepped wall to support the wall 50 to stabilize the frame and maintain the verticality of the frame.

After the excavation to the depth of the stage, the wall 50 is continuously formed by the formwork device 40, and the excavation step is performed, and the total length of the wall 50 and the caulking box seat 10 is applied to reach the design depth of the underground retaining wall.

For example, after a part of the wall 50 having a height of 6 meters is produced by the wall making step, the excavation work is performed, and after a part of the wall 50 produced in the previous step is moved down to a predetermined depth, the excavation operation is stopped. .

Then, the wall forming step is further performed, and a part of the wall 50 of a height of 6 meters is continuously formed on a part of the wall 50 previously produced, and then the template device 40 is stopped, and the excavating device 20 is started to perform excavation work, and the extracting device is started. 30, the soil layer is simultaneously extracted, and water and a separating liquid are respectively injected into the inside and outside of the wall 50.

A portion of the wall 50 produced in the second time is then moved down to another stage depth.

Repeat several cycles of wall fabrication steps and excavation operations until the design depth of the subterranean retaining wall is completed.

With the production of various stages of the wall 50, the steel frame and the mud pipe and the power pipeline therein can be connected one by one, and the load is increased step by step, which is beneficial to the wall drop efficiency and can resist the buoyancy of the groundwater.

The oil pressure jack 70 is supported by the wall jacking wall 50, which can stabilize the verticality of the frame and balance the lateral earth pressure.

After the total length of the wall body 50 and the sinker box 10 reaches the design depth of the underground retaining wall, the lower stencil apparatus 40 is removed first, and the extracting device 30 on the tamping box seat 10 and the excavating device 20 and the steel frame are removed. Equipment (including piping system) and hydraulic jack 70 are sequentially hoisted and dismantled section by section. The excavating device 20 can be reused with the extraction device 30, the hydraulic jack 70, the steel frame and the piping system.

Finally, the finishing step is carried out to finish the finishing of the wall unit of the underground retaining wall, and the hollow part of the wall unit can be backfilled into a solid retaining wall depending on the structural design requirements.

In the above, before the excavation step is performed, it can be used in the caisson A weight gain, such as water, is placed on the seat 10 to increase the weight of the sinking; and the water allows the wall 50 to be hydrated to help enhance its structural strength.

Wherein, in the construction of the unit wall, the adjacent wall unit can also be installed synchronously, and the wall making step and the digging step are the same, and the male and female joints can be arranged adjacent to the adjacent wall unit.

In summary, the underground retaining wall construction method is in the wall manufacturing step, and a part of the wall 50 is first formed by the template device 40. After the strength of the wall 50 is sufficient, the wall is stopped and excavated, and the concrete is removed. The caulking box 10 and the wall 50 are moved down and settled. In the excavation operation, the wall 50 on the caisson box seat 10 has a certain structural strength and the wall is intact without damage to prevent water seepage, and can prevent disasters such as collapse of the surface outside the excavation area during the deep excavation of the subsequent basement. To achieve disaster prevention and improve the safety of work.

The wall 50 constructed by the underground retaining wall in the wall manufacturing step has the function of preventing leakage and water leakage, so that a large amount of stabilizer solution is not needed, which can save the cost of purchase, recovery, detection and monitoring of the stability liquid. Expenditure, and more environmentally friendly and can improve the environmental safety caused by the stability of the liquid.

In addition, the formwork device 40, the excavating device 20, and the extracting device 30 can be recycled and reused, and can also be cost-effective and environmentally friendly.

The wall forming step and the excavation step construction process of the underground retaining wall construction method can be repeated all the time, effectively shortening the construction period.

In addition, the spacing and shape of the inner mold 41 and the outer mold 42 of the stencil apparatus 40 can be adjusted according to the requirements of the groundwater and the geological conditions, and the wall thickness of the soil/water can be made.

And can choose the appropriate size of the caisson seat 10, excavation equipment The device 20 is placed 20 and the extraction device 30.

In addition, since the wall 50 has a certain structural strength, the installation work, the wall making step and the excavation step can be simultaneously performed at the adjacent unit, and the advantage of shortening the construction period can be exerted.

Even with the principle of pressure equalization and communication of the oil pressure system, it is more economical to plan to simultaneously apply a large number of wall units in a large scale.

10‧‧‧預鑄箱箱座

11‧‧‧

12‧‧‧ feet

13‧‧‧Steel toe

14‧‧‧ convex

15‧‧‧ Reserved space

20‧‧‧Excavating device

30‧‧‧ extraction device

40‧‧‧Template equipment

41‧‧‧Inner model

42‧‧‧External model

60‧‧‧ Guide groove

70‧‧‧Hydraulic jack

Claims (7)

The utility model relates to a construction method for underground retaining wall, which comprises: preparing work, finishing the construction site and setting up supporting equipment such as grit chamber and working room, and then constructing guiding groove after lofting and positioning; installation operation, placing the sinking box seat flatly in the preset The wall unit is located in the guiding groove, and an excavating device, an extracting device and a water jet device are arranged in the sinking box seat. And injecting isolation liquid between the caisson and the guide groove, and injecting water into the sinking box seat, keeping the liquid level of the water in the sinking box seat more than 1 meter above the ground elevation, and erecting in the sinking box seat Frame, power line and hydraulic jack for resisting; wall making step, setting template device at the upper end of the wall of the caulking box seat, continuing the steel bar to the reserved rib of the sinking box seat, and the inner mold of the template device, The outer molds are respectively located on both sides of the steel bar and form a pouring space, and the concrete is poured into the pouring space. After the concrete is first solidified to a certain extent, the inner mold and the outer mold are lifted up together by the hydraulic system, and the empty space is poured again. Concrete to the inner mold and the outer mold and waiting for the initial solidification of the concrete, and pressing the frame with the hydraulic jack, repeating the hydraulic pressure to lift the inner mold, the outer mold and the pouring and solidifying action to form the wall of each unit Excavation step, excavation device for excavation, and then the soil is extracted by the extraction device, the sinking box seat and the wall are set down, and the partitioning liquid is injected between the wall and the guiding groove, and the water in the wall is filled. The liquid level of the water holding is higher than the ground elevation by more than 1 meter; after the wall is settled to the depth of the stage, the wall, the continuous frame, the hydraulic jack, the mud pipe and the power line are connected by the template equipment. The excavation step is repeated until the total length of the wall and the sinking box seat reaches the ground The preset depth of the lower retaining wall; after the disassembly operation, the stencil device is first disassembled, and then the extracting device, the frame, the hydraulic jack and the excavating device are hoisted from the sumping box seat and removed step by step, and the wall is synchronized. The hollow section of the body is backfilled and grouted to complete the underground retaining wall of the solid section; and the finishing step is completed to finish the finishing of the wall unit of the underground retaining wall. The underground retaining wall construction method according to claim 1, wherein in the finishing finishing step, the filler can be backfilled in the hollow portion of the wall unit according to the structural design requirement. The underground retaining wall construction method according to claim 1, wherein in the underground retaining wall construction method, a steel toe portion for increasing the lower shear force is disposed outside the seat of the sinker box seat, so as to facilitate the sinking box seat. And the wall that was subsequently produced cut the soil down. The underground retaining wall construction method according to claim 2, wherein in the underground retaining wall construction method, a steel toe portion for increasing the lower shear force is disposed outside the foot of the sinker box seat, so as to facilitate the sinking box seat And the wall that was subsequently produced cut the soil down. The underground retaining wall construction method according to any one of claims 1 to 4, wherein the underground retaining wall construction method is synchronously installed at an adjacent wall unit of the predetermined underground retaining wall, Wall making steps and digging steps. The underground retaining wall construction method according to any one of claims 1 to 4, wherein the wall unit is filled with a bottom grouting method in the finishing finishing step. The underground retaining wall construction method according to claim 5, wherein the wall unit is filled by the bottom grouting method in the finishing finishing step.