Loosening anchoring effect testing structure for cavern of jointed rock mass
By designing a relaxation anchoring effect test structure of the jointed rock mass chamber in hydropower engineering, using a multi-point displacement meter and a drilling acoustic wavemeter to determine the relaxation characteristics, and comparing the anchoring method, the problem of easy relaxation of the jointed rock mass is solved, and the support is optimized Design to ensure the safety and smooth progress of the project.
Patent Information
- Application Number
- CN202420636388.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-29
- Publication Date
- 2024-12-13
- Estimated Expiration
- 2034-03-29
AI Technical Summary
Physical and chemical rock mass is prone to relax in hydropower projects, resulting in reduced load-bearing capacity and damage to surrounding rocks, causing delays in construction periods and safety hazards. It is difficult for the existing technology to effectively evaluate and optimize the anchoring effect.
Design a test structure for relaxation anchoring effect of the stapling rock mass cave chamber. By setting up three anchoring sections and corresponding monitoring sections in the cave chamber, using a multi-point displacement meter and a drilling acoustic wavemeter to determine the relaxation depth and time effects, and compare the different The effect of anchoring method, optimized support design.
Through the testing of the structure, the impact of the anchoring method on the relaxation of the cave chamber can be effectively analyzed, the support design can be optimized, the safety and smooth construction of the cave chamber can be ensured, and the engineering costs and safety risks can be reduced.
Smart Images
Figure CN222166939U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of hydropower engineering construction, and in particular to a test structure for the relaxation anchoring effect of a jointed rock cavern. Background Art
[0002] Large underground caverns are important hub buildings that are indispensable to the construction of hydropower projects. Their safe construction is directly related to the success or failure of the project. As the environment of hydropower underground caverns becomes increasingly complex, joints and fissures develop. The treatment of jointed rock relaxation and its effect evaluation are key technical issues in large underground cavern projects and face huge challenges.
[0003] The main characteristics of jointed rock mass are that it is easy to relax after engineering excavation, and the time effect is significant. After relaxation, the bearing capacity of the rock mass decreases, the self-stabilizing ability weakens, and it is very easy to relax and cause surrounding rock damage such as block falling and collapse, causing construction delays and raising engineering disposal costs. When the relaxation is serious, it may even endanger the lives of construction workers. The difference in the degree of relaxation before and after anchoring of the jointed rock mass cavern is a key indicator for evaluating the support effect and optimizing the subsequent support parameters. Therefore, a suitable test structure for the relaxation anchoring effect of the jointed rock mass cavern is crucial. Utility Model Content
[0004] An embodiment of the present application provides a test structure for the relaxation anchoring effect of a jointed rock cavern. The test structure uses an unsupported structure as a comparison benchmark to analyze the anchoring effect of the jointed rock cavern in response to relaxation, thereby facilitating the goal of safely reinforcing the jointed rock cavern.
[0005] The test structure for the loose anchoring effect of a jointed rock cavern provided in the embodiment of the present application comprises: a first anchoring section, a second anchoring section and a third anchoring section, wherein the first anchoring section, the second anchoring section and the third anchoring section are located in the cavern, and the length directions of the first anchoring section, the second anchoring section and the third anchoring section extend along the axial direction of the cavern; the first anchoring section has a first supporting structure arranged on the cavern ceiling and the side wall, the third anchoring section has a second supporting structure arranged on the cavern bottom, and the cavern ceiling, the side wall and the bottom of the second anchoring section are not provided with supporting structures;
[0006] The first monitoring section and the second monitoring section, the first monitoring section is provided with a plurality of multi-point displacement meters, the second monitoring section is provided with a plurality of borehole sonic instruments, the multi-point displacement meters and the borehole sonic instruments are used to measure the depth and degree of cavern relaxation and the time effect of cavern relaxation; the first anchoring section, the second anchoring section and the third anchoring section are all provided with the first monitoring section and the second monitoring section.
[0007] In addition, the jointed rock mass cavern relaxation anchoring effect test structure provided in the embodiment of the present application may also have the following additional technical features:
[0008] In an optional solution, the first support structure includes anchor spraying support arranged on the cavern ceiling and side walls, and the second support structure includes a plurality of pre-buried anchor rods arranged on the cavern bottom.
[0009] In an optional solution, the cavern is divided into a first excavation layer, a second excavation layer and a third excavation layer according to the excavation order during excavation, and the pre-buried anchor rods are formed by drilling holes vertically to the bottom of the cavern and pre-buried after the second excavation layer is completed.
[0010] In an optional scheme, the first monitoring section and the second monitoring section include monitoring boreholes, and the monitoring boreholes are located in the top arch, side wall and bottom plate of the cavern, and the number of the monitoring boreholes located in the first monitoring section and the second monitoring section is no less than 8.
[0011] In an optional solution, the lengths of the first anchoring section, the second anchoring section and the third anchoring section are all not less than 30 m, and the first anchoring section, the second anchoring section and the third anchoring section are arranged in sequence along the axial direction of the cavern.
[0012] The beneficial effects of the embodiments of the present application are:
[0013] The test structure for the relaxation anchoring effect of the jointed rock cavern in the embodiment of the present application divides the cavern into three different anchoring sections (i.e., three test sections), and two monitoring sections are respectively set in each anchoring section. During the test, the anchoring section without a support structure is used as the reference section. By comparing the test results of the reference section with those of other anchoring sections, the relaxation characteristics of the rock mass around the jointed rock cavern are determined, and then the influence of the anchoring method on the relaxation of the cavern is analyzed, the support design of the cavern is optimized, and the safe and smooth construction of the cavern is further ensured.
[0014] It should be understood that the foregoing general description and the following detailed description are exemplary only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the planar layout structure of the test structure for the loose anchoring effect of the jointed rock mass cavern in this application;
[0016] Figure 2 for Figure 1 AA cross-sectional structure diagram in;
[0017] Figure 3 for Figure 1 Schematic diagram of the BB cross-sectional structure.
[0018] Figure numerals: first anchoring section 1, second anchoring section 2, third anchoring section 3, cavern 4, first monitoring section 5, multi-point displacement meter 51, second monitoring section 6, drilling sonic instrument 61, embedded anchor rod 7, first excavation layer 8, second excavation layer 9, third excavation layer 10.
[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application. DETAILED DESCRIPTION
[0020] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.
[0021] It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.
[0022] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.
[0023] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.
[0024] It should be noted that the directional words such as "upper", "lower", "left", and "right" described in the embodiments of the present application are described at the angles shown in the accompanying drawings and should not be understood as limiting the embodiments of the present application. In addition, in the context, it is also necessary to understand that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.
[0025] After the excavation of jointed rock caverns, relaxation failure will inevitably occur, and even instability disasters such as large deformation and collapse may occur. The difference in the test structure of the relaxation anchoring effect of jointed rock caverns means that there are differences in the anchoring form, anchoring timing, monitoring system, etc., which may lead to differences in the treatment effect of surrounding rock relaxation and the judgment of the degree of surrounding rock relaxation. Therefore, the selection of a reasonable test structure for the relaxation anchoring effect of jointed rock caverns is very important to the stability of the entire jointed rock cavern and even the stability of the entire underground project.
[0026] like Figure 1-3 As shown, the embodiment of the present application provides a test structure for the relaxation anchoring effect of a jointed rock cavern, which is mainly used for hydropower underground projects, especially for easily relaxed jointed rock cavern projects, especially for large underground cavern projects with an equivalent cavern diameter of more than 10m. Of course, the application field of the test structure for the relaxation anchoring effect of a jointed rock cavern in the embodiment of the present application is not limited to the description in this article, and can also be used in the relaxation anchoring effect test environment of rock caverns in other environments, which is not specifically limited in this article.
[0027] The test structure of the loose anchoring effect of the jointed rock cavern mainly includes the first anchoring section 1, the second anchoring section 2, the third anchoring section 3, the first monitoring section 5, and the second monitoring section 6. Among them, the first anchoring section 1, the second anchoring section 2 and the third anchoring section 3 are located in the cavern 4, and the length direction of the first anchoring section 1, the second anchoring section 2 and the third anchoring section 3 extends along the axial direction of the cavern 4; the first anchoring section 1 has a first supporting structure arranged on the top arch and the side wall of the cavern 4, the third anchoring section 3 has a second supporting structure arranged on the bottom of the cavern 4, and the top arch, the side wall and the bottom of the cavern 4 of the second anchoring section 2 are not provided with supporting structures.
[0028] The first monitoring section 5 is provided with a plurality of multi-point displacement meters 51, and the second monitoring section 6 is provided with a plurality of drilling sonic instruments 61. The multi-point displacement meters 51 and the drilling sonic instruments 61 are used to measure the depth and degree of relaxation of the cavern 4 and the time effect of relaxation of the cavern 4; the first anchoring section 1, the second anchoring section 2 and the third anchoring section 3 are all provided with a first monitoring section 5 and a second monitoring section 6.
[0029] In this embodiment, the first anchoring section 1, the second anchoring section 2, and the third anchoring section 3 are all part of the cavern 4. During the test, a jointed rock cavern 4 at a suitable location can be selected according to experimental requirements and the first anchoring section 1, the second anchoring section 2, and the third anchoring section 3 can be arranged. In addition, the lengths of the first anchoring section 1, the second anchoring section 2, and the third anchoring section 3, and the number and positions of the first monitoring section 5 and the second monitoring section 6 can be preset and adjusted according to the actual environment, and this article does not make specific limitations on this.
[0030] In this embodiment, the test structure for the loosening anchoring effect of the jointed rock cavern divides the cavern 4 into three different anchoring sections (i.e., three test sections), and two monitoring sections are respectively set in each anchoring section. During the test, the anchoring section without supporting structure is used as the reference section. By comparing the test results of the reference section with those of other anchoring sections, the loosening characteristics of the rock mass around the jointed rock cavern 4 are determined, and then the influence of the anchoring method on the loosening of the cavern 4 is analyzed, the support design of the cavern 4 is optimized, and the safe and smooth construction of the cavern 4 is further ensured. In the process of test comparison, the first anchoring section 1 can be tested and compared with the second anchoring section 2 to evaluate the control effect of the top arch and side wall anchoring measures on the loosening of the cavern 4; the third anchoring section 3 can be tested and compared with the second anchoring section 2 to evaluate the control effect of the bottom plate anchoring measures on the loosening of the cavern 4.
[0031] like Figure 1-3 As shown, in a specific embodiment, the first support structure includes anchor spraying support arranged on the top arch and side wall of the cavern 4, and the second support structure includes a plurality of pre-buried anchor rods 7 arranged at the bottom of the cavern 4. When the cavern 4 is excavated, it is divided into a first excavation layer 8, a second excavation layer 9 and a third excavation layer 10 according to the excavation sequence. The first excavation layer 8, the second excavation layer 9 and the third excavation layer 10 are also arranged in sequence from top to bottom along the vertical direction of the cavern 4. After the second excavation layer 9 is completed, the pre-buried anchor rods 7 are drilled vertically to the bottom of the cavern 4 and pre-buried.
[0032] like Figure 1-3 As shown, in a specific embodiment, the first monitoring section 5 and the second monitoring section 6 include monitoring boreholes, which are located in the top arch, side wall and bottom plate of the cavern 4, and the number of monitoring boreholes located in the first monitoring section 5 and the second monitoring section 6 is not less than 8. By arranging monitoring at different positions of the cavern 4 and ensuring a certain number of monitoring points, the comprehensiveness and accuracy of the monitoring results can be ensured. In addition, the lengths of the first anchoring section 1, the second anchoring section 2 and the third anchoring section 3 are not less than 30m, and the first anchoring section 1, the second anchoring section 2 and the third anchoring section 3 are arranged in sequence along the axial direction of the cavern 4.
[0033] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims
1. A test structure for the loose anchoring effect of a jointed rock cavern, characterized in that: include: A first anchoring section, a second anchoring section and a third anchoring section, wherein the first anchoring section, the second anchoring section and the third anchoring section are located in the cavern, and the length directions of the first anchoring section, the second anchoring section and the third anchoring section extend along the axial direction of the cavern; the first anchoring section has a first supporting structure arranged on the cavern ceiling and the side wall, the third anchoring section has a second supporting structure arranged on the cavern bottom, and the cavern ceiling, the side wall and the bottom of the second anchoring section are not provided with supporting structures; The first monitoring section and the second monitoring section, the first monitoring section is provided with a plurality of multi-point displacement meters, the second monitoring section is provided with a plurality of borehole sonic instruments, the multi-point displacement meters and the borehole sonic instruments are used to measure the depth and degree of cavern relaxation and the time effect of cavern relaxation; the first anchoring section, the second anchoring section and the third anchoring section are all provided with the first monitoring section and the second monitoring section.
2. The test structure for the loose anchoring effect of a jointed rock cavern according to claim 1, characterized in that: The first support structure includes anchor spraying support arranged on the cavern top arch and side walls, and the second support structure includes a plurality of pre-buried anchor rods arranged on the cavern bottom.
3. The test structure for the loose anchoring effect of a jointed rock mass cavern according to claim 2, characterized in that: The cavern is divided into a first excavation layer, a second excavation layer and a third excavation layer according to the excavation order during excavation. After the second excavation layer is completed, the pre-buried anchor rods are drilled vertically to the bottom of the cavern and pre-buried.
4. The test structure for the loose anchoring effect of a jointed rock cavern according to any one of claims 1 to 3, characterized in that: The first monitoring section and the second monitoring section include monitoring boreholes, which are located in the top arch, side walls and bottom plate of the cavern, and the number of the monitoring boreholes located in the first monitoring section and the second monitoring section is no less than 8.
5. The test structure for the loose anchoring effect of a jointed rock cavern according to claim 4, characterized in that: The lengths of the first anchoring section, the second anchoring section and the third anchoring section are all not less than 30 m, and the first anchoring section, the second anchoring section and the third anchoring section are arranged in sequence along the axial direction of the cavern.