Construction method of steel tube concrete wall structure for soft geological structure

Abstract

The present invention relates to the technical field of water conservancy and hydropower engineering, and in particular to a method for constructing a steel tube concrete wall structure for a weak geological structure, which comprises the following steps: a. determining the construction working surface of the weak geological structure that needs to be reinforced; b. constructing a pipe well by a pipe jacking machine, and at the same time, the pipe jacking machine also installs a steel casing at a corresponding position of the pipe well, and grouting holes are arranged on the circumference of the steel casing; c. withdrawing the pipe jacking machine from the outside of the pipe well; d. pouring concrete into the steel casing, and the concrete enters the rock mass outside the steel casing through the grouting holes, and the construction of the steel tube concrete pipe well is completed after the concrete reaches the specified strength. The pipe jacking machine is used for the first time in the construction of a steel tube concrete wall structure, thereby significantly reducing the construction process of the pipe well, improving the construction effect of the pipe well, avoiding safety risks such as local block falling, and improving construction safety.

Description

Technical Field

[0001] The invention relates to the technical field of water conservancy and hydropower engineering, and in particular to a construction method of a steel tube concrete wall structure for soft geological structures. Background Art

[0002] In water conservancy and hydropower projects, for the safety of buildings such as dams, it is necessary to reinforce weak geological structures. A common method is to set up a steel tube concrete wall structure in the weak geological structure. The construction steps for setting up the steel tube concrete wall structure are: first determine the construction working surface of the weak geological structure that needs to be reinforced, and then excavate the pipe well. After the construction of the pipe well is completed, install the steel casing at the corresponding position of the pipe well, and finally pour concrete into the steel casing. The concrete enters the rock outside the steel casing through the grouting hole. After the concrete reaches the specified strength, the construction of the steel tube concrete pipe well is completed. If only one steel tube concrete pipe well is set up, the construction of the steel tube concrete wall structure is completed at this time. If multiple steel tube concrete pipe wells are required, after completing one steel tube concrete pipe well, continue to construct the next steel tube concrete pipe well according to the above steps. The construction of the steel tube concrete wall structure is completed until all steel tube concrete pipe wells are completed.

[0003] At present, pipe wells are often constructed by blasting, and the specific steps are: upper layer blasting excavation → manual mechanical slag secondary transportation → lower layer blasting excavation cycle. This method causes great relaxation of the surrounding rock after blasting, which is not conducive to the initial stability of the well chamber and is prone to cause safety risks such as local block falling. It has low safety and involves processes such as drilling, charging, blasting, and slag removal. There are many processes and the construction efficiency is low, which in turn affects the construction efficiency of the steel tube concrete wall structure. Summary of the invention

[0004] The technical problem solved by the invention is to provide a steel tube concrete wall structure construction method for soft geological structures with high safety and high construction effect.

[0005] The technical solution adopted by the present invention to solve the technical problem is: a construction method of a steel tube concrete wall structure for a weak geological structure, comprising the following steps:

[0006] a. Determine the construction surface of the weak geological structure that needs to be reinforced;

[0007] b. The pipe well is constructed by a pipe jacking machine, and the pipe jacking machine also installs the steel casing at the corresponding position of the pipe well, and grouting holes are arranged on the circumference of the steel casing;

[0008] c. Withdraw the pipe jacking machine out of the pipe well;

[0009] d. Pour concrete into the steel casing. The concrete enters the rock outside the steel casing through the grouting holes. When the concrete reaches the specified strength, the construction of the steel tube concrete well is completed.

[0010] Furthermore, the pipe shaft is a vertical shaft or an inclined shaft.

[0011] Furthermore, before the pipe jacking machine carries out pipe well construction, the number, depth and inclination of the pipe wells are determined according to the width of the construction working surface.

[0012] Furthermore, when the width of the construction working surface is less than or equal to 1 m, the number of the steel tube concrete pipe shaft is one; when the width of the construction working surface is greater than 1 m, the number of the steel tube concrete pipe shaft is multiple.

[0013] Furthermore, when there are multiple concrete-filled steel tube shafts, steps b to d are repeated to complete the construction of all concrete-filled steel tube shafts in sequence, thereby completing the construction of the concrete-filled steel tube wall structure.

[0014] Furthermore, the distance between adjacent concrete-filled steel tube shafts is 0.3 m.

[0015] Furthermore, the pipe jacking machine is withdrawn to the outside of the pipe well by a winch.

[0016] The beneficial effects of the present invention are as follows: the present invention constructs a pipe well through a pipe jacking machine, and at the same time the pipe jacking machine also installs a steel casing at a corresponding position of the pipe well, the pipe well is equivalent to a pipe trough in pipeline laying construction, and the steel casing is equivalent to a pipe in pipeline laying construction, and the pipe jacking machine is used for the first time in the construction of a steel tube concrete wall structure, thereby significantly reducing the construction process of the pipe well, improving the construction effect of the pipe well, avoiding safety risks such as local block falling, and improving construction safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the steel tube concrete wall structure during construction;

[0018] Figure 2 yes Figure 1 Schematic diagram of the middle edge AA;

[0019] Marked as: weak geological structure 1, construction working surface 2, steel casing 3, grouting hole 4, steel tube concrete well 5. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] like Figure 1 , Figure 2 As shown, the steel tube concrete wall structure construction method for soft geological structure of the present invention comprises the following steps:

[0022] a. Determine the construction working surface 2 of the weak geological structure 1 that needs to be reinforced;

[0023] b. The pipe well is constructed by a pipe jacking machine, and the pipe jacking machine also installs a steel casing 3 at a corresponding position of the pipe well. Grouting holes 4 are arranged on the circumference of the steel casing 3. The pipe well is a vertical well or an inclined well;

[0024] c. Withdraw the pipe jacking machine out of the pipe well;

[0025] d. Pour concrete into the steel casing 3. The concrete enters the rock mass outside the steel casing 3 through the grouting holes 4. After the concrete reaches the specified strength, the construction of the steel tube concrete well 5 is completed.

[0026] At present, pipe jacking machines are used in the laying of pipelines. The construction technology of pipe jacking machines is a non-excavation pipeline laying construction technology, that is, no excavation is required. Pipe jacking machine excavation technology is used to lay pipelines underground. It has the advantages of no impact on the surrounding environment or less impact, small construction site, low noise, and the ability to work deep underground. Common pipe jacking machines include a backrest, a head guide rail, a cylinder and a cylinder rack, a pressure equalizing ring, and a mud pump. The power supply unit, hydraulic unit, and control unit of the pipe jacking machine are placed on the ground. The pipe jacking machine consists of a cutter head, a transmission system, and a power system. A laser theodolite is installed in the starting well, and a light target is installed in the pipe jacking machine. From the interface of the ground operating table, the machine posture can be monitored in time, and the correction cylinder behind the cutter head is used to control the four directions of the pipe jacking machine to correct the deflection and ensure that the pipe jacking machine is pushed forward along the established axis. The pipe jacking machine relies on an electric motor to drive the cutterhead to rotate, and the cutterhead cuts the soil. The mud inlet and outlet system is responsible for the circulation of the working mud, carrying the debris out of the machine. The main jacking cylinder pushes the pipe jacking machine forward. During long-distance jacking, when the thrust of the main jacking cylinder is insufficient, a relay room needs to be placed to provide continued jacking force until the construction is completed.

[0027] The construction surface 2 of each weak geological structure 1 that needs to be reinforced is different. Before the pipe jacking machine performs pipe well construction, the number, direction, depth and inclination of the pipe well are determined according to the width of the construction surface 2. When the width of the construction surface 2 is less than or equal to 1m, the number of steel tube concrete pipe wells 5 is one; when the width of the construction surface 2 is greater than 1m, the number of steel tube concrete pipe wells 5 is multiple, and 2 or more rows can be set. According to the conditions of the weak geological structure, the diameter of the single steel tube concrete pipe well 5, the number of rows of pipe wells, the spacing between rows, and the sequence of staggered construction are determined, and the position of each steel tube concrete pipe well 5 is determined. In order to ensure the safety of construction, when the number of steel tube concrete pipe wells 5 is multiple, repeat steps bd to complete the construction of all steel tube concrete pipe wells 5 in sequence, that is, complete the construction of one steel tube concrete pipe well 5, and then complete the construction of the next steel tube concrete pipe well 5, thereby completing the construction of the steel tube concrete pipe wall structure. In order to ensure the effect of the steel tube concrete shaft 5, the distance between adjacent steel tube concrete shafts 5 is 0.3m.

[0028] When the depth of the pipe well is deeper, there are multiple sections of steel casing 3. After the pipe jacking machine installs one section of steel casing 3 at the corresponding position of the pipe well, it welds this section of steel casing 3 with the next section of steel casing 3. The pipe jacking machine continues to advance forward and installs the next section of steel casing 3 at the corresponding position of the pipe well, and so on, until all steel casing 3 are installed in place.

[0029] In order to facilitate the withdrawal of the pipe jacking machine out of the pipe shaft, in step c, the pipe jacking machine is withdrawn out of the pipe shaft by a winch.

[0030] To sum up, the present application adopts a pipe jacking machine to carry out the construction of a pipe well, and at the same time, the pipe jacking machine also installs the steel casing 3 at the corresponding position of the pipe well. The pipe well is equivalent to the pipe trough in the pipeline laying construction, and the steel casing 3 is equivalent to the pipe in the pipeline laying construction. The pipe jacking machine is used for the first time in the construction of steel tube concrete wall structure, thereby significantly reducing the construction process of the pipe well, improving the construction effect of the pipe well, avoiding safety risks such as local block falling, and improving construction safety.

Claims

1. A method for constructing a steel tube concrete wall structure for a soft geological structure, characterized in that: The steps include: a. Determine the construction work surface (2) of the weak geological structure (1) that needs to be reinforced; b. The pipe well is constructed by a pipe jacking machine, and the pipe jacking machine also installs a steel casing (3) at a corresponding position of the pipe well, and a grouting hole (4) is arranged on the circumference of the steel casing (3); c. Withdraw the pipe jacking machine out of the pipe well; d. Pour concrete into the steel casing (3), and the concrete enters the rock mass outside the steel casing (3) through the grouting holes (4). After the concrete reaches a specified strength, the construction of the steel tube concrete well (5) is completed.

2. The method for constructing a steel tube concrete wall structure for a weak geological structure according to claim 1, characterized in that: A pipe shaft is a vertical shaft or an inclined shaft.

3. The method for constructing a steel tube concrete wall structure for a soft geological structure according to claim 1, characterized in that: Before the pipe jacking machine carries out pipe well construction, the number, depth and inclination of the pipe wells are determined according to the width of the construction working surface (2).

4. The method for constructing a steel tube concrete wall structure for a soft geological structure according to claim 1, characterized in that: When the width of the construction working surface (2) is less than or equal to 1 m, the number of the steel tube concrete well (5) is one; when the width of the construction working surface (2) is greater than 1 m, the number of the steel tube concrete well (5) is multiple.

5. The method for constructing a steel tube concrete wall structure for a soft geological structure as claimed in claim 4, characterized in that: When there are multiple steel tube concrete wells (5), repeat steps bd to complete the construction of all steel tube concrete wells (5) in sequence, thereby completing the construction of the steel tube concrete wall structure.

6. The method for constructing a steel tube concrete wall structure for a soft geological structure according to claim 5, characterized in that: The distance between adjacent steel tube concrete wells (5) is 0.3m.

7. The method for constructing a steel tube concrete wall structure for a soft geological structure according to any one of claims 1 to 6, characterized in that: The pipe jacking machine is withdrawn to the outside of the pipe shaft through the winch.

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