Measurement method and system for deformation of initial support steel arch in tunnel

Abstract

The present invention relates to the technical field of deformation monitoring, and particularly to a measurement method and system for the deformation of the initial support steel arch of a tunnel, including: obtaining the strain data of each strain rod relative to the waist measurement point at each deformation monitoring point during the period to be measured; analyzing the movement of each strain rod according to the strain data corresponding to each deformation monitoring point during the period to be measured, and analyzing the deformation of different strain rods at the same deformation monitoring point in combination with the physical parameter information of the strain rods to obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured; obtaining the torsion angle detection index of each deformation monitoring point during the period to be measured according to the deformation detection index and the distance distribution between each deformation monitoring point and the waist measurement point; and judging the deformation early warning situation of the tunnel steel arch during the period to be measured by using the deformation detection index and the torsion angle detection index. The present invention makes the deformation monitoring result of the steel arch more comprehensive and improves the monitoring safety.

Description

Technical Field

[0001] The present invention relates to the technical field of deformation monitoring, and particularly to a measurement method and system applicable to the deformation of the steel arch in the initial support of a tunnel. Background Art

[0002] The initial support of a tunnel refers to the temporary support measures taken for the excavated slopes and the top during the tunnel excavation process to ensure the stability of the tunnel structure. Its main function is to reinforce the surrounding rock, prevent the surrounding rock from loosening and excessive deformation, and provide safety guarantees for subsequent construction. The initial support usually includes shotcrete, rock bolts, and steel arches, etc. Through these measures, the stress release and deformation of the surrounding rock can be effectively controlled, and at the same time, a safe working environment can be provided for the subsequent permanent lining.

[0003] As an important part of the initial support of a tunnel, the steel arch mainly provides support resistance for the initial support of the tunnel, restricts the deformation of the surrounding rock, and at the same time serves as the back support point for the advanced support; therefore, the steel arch plays a crucial role in the initial support of the tunnel, and its deformation directly affects the safety and stability of tunnel construction.

[0004] During the initial support of a tunnel, the external load pressure on the initial surrounding rock of the tunnel will have a certain change period until it stabilizes. Continuous detection during this period can better ensure construction safety. However, when using the traditional total station measurement method for steel arch deformation monitoring, there are certain requirements for the setting position of the total station. Long-term monitoring will affect tunnel traffic, and the cost is relatively high. Limited by the monitoring angle, it is impossible to better monitor the torsional deformation of the steel arch in real time. Summary of the Invention

[0005] In order to solve the technical problem that the existing methods for monitoring the deformation of the steel arch in the initial stage of a tunnel are limited by various objective factors and cannot better monitor the torsional deformation of the steel arch in real time, the purpose of the present invention is to provide a measurement method and system applicable to the deformation of the steel arch in the initial support of a tunnel. The specific technical solutions adopted are as follows:

[0006] In a first aspect, the present invention provides a measurement method applicable to the deformation of the steel arch in the initial support of a tunnel, including:

[0007] Waist measurement points are set at the waist of the steel arch, and deformation monitoring points are set at positions adjacent to each waist measurement point; a strain rod is provided between the waist measurement point and the deformation monitoring point; strain data of each strain rod relative to the waist measurement point at each deformation monitoring point during the period to be measured is obtained;

[0008] According to the strain data corresponding to each deformation monitoring point during the period to be measured, the movement of each strain rod is analyzed, and the deformation of different strain rods at the same deformation monitoring point is analyzed in combination with the physical parameter information of the strain rod to obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured;

[0009] According to the deformation detection index and the distance distribution between each deformation monitoring point and the waist measuring point, the torsion angle detection index of each deformation monitoring point during the period to be measured is obtained;

[0010] Use the deformation detection index and the torsion angle detection index to judge the deformation early warning situation of the tunnel steel arch during the period to be measured.

[0011] Preferably, the strain data includes an axial strain value and a radial strain value.

[0012] Preferably, according to the strain data corresponding to each deformation monitoring point during the period to be measured, analyze the movement of each strain rod, and combine the physical parameter information of the strain rod to analyze the deformation of different strain rods at the same deformation monitoring point, so as to obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured, specifically including:

[0013] According to the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding stress rod, obtain the axial displacement data of each strain rod at each deformation monitoring point;

[0014] According to the radial strain value of each strain rod at each deformation monitoring point and the physical parameters of the corresponding stress rod, obtain the radial displacement data of each strain rod at each deformation monitoring point;

[0015] According to the axial displacement data and radial displacement data of each strain rod at each deformation monitoring point during the period to be measured, and combining the length data of the corresponding stress rod, obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured.

[0016] Preferably, the step of obtaining the axial displacement data of each strain rod at each deformation monitoring point according to the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding stress rod specifically includes:

[0017] Based on the product of the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding strain rod, determine the axial displacement data of each strain rod at each deformation monitoring point.

[0018] Preferably, the step of obtaining the radial displacement data of each strain rod at each deformation monitoring point according to the radial strain value of each strain rod at each deformation monitoring point and the physical parameters of the corresponding stress rod specifically includes:

[0019] Based on the product relationship and ratio relationship between the radial strain value of each strain rod at each deformation monitoring point and the diameter data and the length data, construct a function calculation formula for the radial strain value, and solve the radial displacement data of each strain rod at each deformation monitoring point based on the function calculation formula.

[0020] Preferably, based on the axial displacement data and radial displacement data of each strain rod at each deformation monitoring point within the time period to be measured, and in combination with the length data of the corresponding stress rod, the deformation detection index of each strain rod at each deformation monitoring point within the time period to be measured is obtained, specifically including:

[0021] For any strain rod at any deformation monitoring point, taking the waist measurement point as the origin, based on the length data of the strain rod and the initial inclination angle of the strain rod, the initial polar coordinates of the strain rod relative to the waist measurement point are obtained;

[0022] The axial displacement data of the strain rod at each moment within the time period to be measured is obtained, and in combination with the radial coordinate of the initial polar coordinates, the radial coordinate of the deformation polar coordinates of the strain rod at each moment is determined;

[0023] The radial displacement data of the strain rod at each moment within the time period to be measured is obtained, and in combination with the axial displacement data and length data of the strain rod at the corresponding moment, the deformation angle of the strain rod at each moment is determined; the sum value of the deformation angle and the initial inclination angle of the strain rod is used as the polar angle coordinate of the deformation polar coordinates of the strain rod at each moment;

[0024] Based on the distance between the deformation polar coordinates at the end moment and the initial moment of the time period to be measured, the deformation detection index of the strain rod at the deformation monitoring point within the time period to be measured is obtained.

[0025] Preferably, based on the deformation detection index and the distance distribution between each deformation monitoring point and the waist measurement point, the torsion angle detection index of each deformation monitoring point within the time period to be measured is obtained, specifically including:

[0026] For any deformation monitoring point, the actual length between the deformation monitoring point and the waist measurement point is obtained, and the difference between the deformation detection indexes of two strain rods at the same deformation monitoring point within the time period to be measured is calculated to obtain the deformation difference value of the deformation monitoring point within the time period to be measured; the arctangent function value of the ratio of the deformation difference value to the actual length is used as the torsion angle detection index of the deformation monitoring point within the time period to be measured.

[0027] Preferably, using the deformation detection index and the torsion angle detection index to judge the deformation early warning situation of the tunnel steel arch within the time period to be measured, specifically including:

[0028] The standard deformation data and standard torsion data of the tunnel steel arch deformation are obtained; according to the comparison results between the deformation detection indexes corresponding to each deformation monitoring point within the time period to be measured and the standard deformation data, and the comparison results between the torsion angle detection indexes and the standard torsion data, the deformation early warning situation of the tunnel steel arch within the time period to be measured is obtained.

[0029] Preferably, according to the comparison results of the deformation detection indexes corresponding to each deformation monitoring point and the standard deformation data within the time period to be measured, and the comparison results of the torsion angle detection indexes and the standard torsion data, the deformation early warning situation of the tunnel steel arch within the time period to be measured is obtained, which specifically includes:

[0030] When the deformation detection index corresponding to each deformation monitoring point within the time period to be measured exceeds the standard deformation data, or the torsion angle detection index exceeds the standard torsion data, a deformation early warning of the tunnel steel arch is carried out within the time period to be measured; when the deformation detection index corresponding to each deformation monitoring point within the time period to be measured does not exceed the standard deformation data, and the torsion angle detection index does not exceed the standard torsion data, no deformation early warning of the tunnel steel arch is carried out within the time period to be measured.

[0031] In a second aspect, the present invention provides a measurement system applicable to the deformation of the initial support steel arch of a tunnel, including a memory, a processor, and a computer program stored on the memory and running on the processor. When the computer program is executed by the processor, the steps of the measurement method applicable to the deformation of the initial support steel arch of a tunnel are implemented.

[0032] The embodiments of the present invention have at least the following beneficial effects:

[0033] First, in the data acquisition stage, by setting a strain rod between the waist measurement point and the deformation monitoring point, the displacement or deformation situation at the deformation monitoring point is converted into the strain situation of the strain rod, providing a data basis for the subsequent analysis of the displacement deformation situation and the torsion deformation situation. Then, combining the physical parameter data of the strain rod and the distance distribution between the deformation monitoring point and the waist measurement point, the displacement deformation and torsion deformation situations are analyzed more specifically, and the deformation amount performance of the deformation monitoring point is deduced by using geometric relations, improving the measurement accuracy. Compared with the traditional monitoring method, the present invention can realize real-time monitoring of the deformation state, does not need to occupy the tunnel space for a long time, reduces the impact on traffic, reduces costs, and at the same time, not only detects the deformation amount of the steel arch, but also conducts torsion deformation detection of the steel arch, making the steel arch deformation monitoring result more comprehensive and improving the monitoring safety. Description of the Drawings

[0034] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0035] Figure 1 It is a step flowchart of the measurement method applicable to the deformation of the initial support steel arch of the tunnel provided by the present invention;

[0036] Figure 2 It is a schematic diagram of the tunnel cross-section structure provided by the present invention;

[0037] Figure 3 It is a schematic diagram of the structure of the strain rod provided by the present invention;

[0038] Figure 4 It is a schematic diagram of the structure of the strain rod arranged on the steel arch section provided by the present invention;

[0039] Figure 5 It is a partial structure schematic diagram of the strain rod provided by the present invention;

[0040] Figure 6 It is a step flow chart of the method for obtaining the deformation detection index provided by the present invention;

[0041] Among them, the labels in the figure are: A, the apex of the arch; B, the measuring point on the left waist; C, the measuring point on the right waist; a, the first connection point; b, the second connection point; c, the third connection point; d, the fourth connection point; 1, the left strain rod; 2, the right strain rod; x, the axial direction; y, the radial direction. Detailed implementation manners

[0042] In order to further elaborate on the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following, in combination with the accompanying drawings and preferred embodiments, details the specific implementation manners, structures, features and effects of the measurement method and system for the deformation of the steel arch in the initial support of the tunnel proposed according to the present invention.

[0043] Before introducing the specific solutions provided by the embodiments of the present application, the implementation scenarios in the present application are explained to facilitate the understanding of those skilled in the art, and are not used to limit the present application.

[0044] The initial support of the tunnel is a temporary or permanent structure constructed immediately after the tunnel excavation, aiming to quickly stabilize the surrounding rock, prevent collapse, and provide a safe environment for subsequent construction (such as the secondary lining). Its core function is to balance the stress of the surrounding rock and control the deformation in an active or passive manner. The initial support is usually composed of a combination of various materials and technologies, and the main steps include:

[0045] Shotcrete: Adopting wet shotcrete or dry shotcrete technology, a layer of concrete protective layer is quickly formed on the excavation surface to seal the rock surface cracks and prevent weathering and spalling. Anchor rod system: Fully grouted anchor rod: Combined with the surrounding rock through grouting to form a reinforcement ring. Prestressed anchor rod: Actively apply prestress to improve the stress state of the surrounding rock. Self-drilling anchor rod: Suitable for fractured strata, with both drilling and anchoring functions. Steel arch (steel support): The core load-bearing member, providing circumferential stiffness and forming a composite structure with shotcrete. Reinforcement mesh: Laid between the rock surface and shotcrete to prevent the concrete from shrinking and cracking and improve the integrity.

[0046] The core functions of the steel arch in the initial support are as follows:

[0047] Three-dimensional stress bearing: Resisting the bending stress of the surrounding rock through the section moment of inertia of the section steel or grid, which is especially suitable for tunnels with high ground stress or shallow-buried and eccentric pressure. Deformation coordination control: Working together with shotcrete to limit the expansion of the plastic zone of the surrounding rock. The yield strength of the steel arch can provide a certain ductility deformation ability to avoid brittle failure. Temporary load bearing during construction: Independently bearing most of the loads before the strength of the shotcrete reaches the design value to ensure the stability of the heading face. Formation adaptability adjustment: Adapting to different surrounding rock grades by adjusting the arch spacing (such as 0.5 m to 1.2 m) and section size (such as I20 to I25 section steel). Double-layer arches can be used to strengthen the fractured zone. Spatial positioning reference: Providing a spatial reference system for the subsequent layout of bolts and wire meshes to ensure the geometric accuracy of the support system.

[0048] In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures, or characteristics in one or more embodiments can be combined in any suitable form.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this invention belongs.

[0050] The following specifically describes the specific solutions of the measurement method and system for steel arch deformation applicable to tunnel initial support provided by the present invention with reference to the accompanying drawings.

[0051] Please refer to Figure 1 , which shows a flowchart of the steps of a measurement method for steel arch deformation applicable to tunnel initial support provided by an embodiment of the present invention. The method includes the following steps:

[0052] Step S100, setting waist measurement points at the waist of the steel arch, and setting deformation monitoring points at positions adjacent to each waist measurement point; a strain rod is provided between the waist measurement point and the deformation monitoring point; obtaining the strain data of each strain rod relative to the waist measurement point at each deformation monitoring point during the period to be measured.

[0053] First, to ensure the safety and stability during the tunnel excavation process, during the tunnel excavation process, for the tunnel section that needs to be monitored, measurement points are set at the waist of the section, as Figure 2 shown, the waist measurement points include the left waist measurement point B and the right waist measurement point C, Figure 2 also shows the position of the arch apex A.

[0054] Then, a deformation monitoring point is set at the adjacent position of each waist measuring point. Specifically, after the steel arch is installed, strain rods are placed between the left waist measuring point B and the right waist measuring point C of the steel arch and the initial support steel arch connection points, respectively. The pressure between the measuring point and the steel arch connection point is measured by the strain rod to reflect the deformation of each steel arch connection point. When installing the strain rod, the two sections of the strain rod can be fixed at the welding point of the steel arch connection point. Figure 3 As shown, the first connection point a, the second connection point b, the third connection point c and the fourth connection point d are all deformation monitoring points set in this embodiment, and a strain rod is provided between each deformation monitoring point and the nearest adjacent waist measuring point.

[0055] Furthermore, since the steel material of the steel arch is usually "I" steel, the steel arch usually has a certain width. Therefore, during installation, a double strain rod can be set between the steel arch measuring point and the connection point. The double strain rod can be used to reflect the deformation and stress conditions on both sides of the steel arch to measure the torsional deformation of the steel arch. The cross-section of the steel arch is shown in the figure. Figure 4 As shown, the left waist measuring point B includes a left strain rod 1 and a right strain rod 2. It should be noted that the material of the strain rod can be selected to be consistent with the steel arch, the diameter is selected to be 15-20mm, and the full-bridge strain gauge is attached to the surface. It is connected to the stainless steel fixture and the steel arch through the universal adjustment bracket, and the positioning error is less than or equal to 1mm.

[0056] It can be seen from this that the deformation monitoring point where the connection point corresponding to each waist measuring point is located includes two strain rods. It should be understandable that subsequent characteristic analysis was carried out on the stress and deformation conditions of each strain rod between the waist measuring point on the steel arch and each deformation monitoring point.

[0057] Finally, the strain data of each strain rod relative to the waist measuring point at each deformation monitoring point in the test time period is obtained, and the strain data includes axial strain value and radial strain value. In this embodiment, the initial tilt angle of the strain rod is measured by an encoder or other angle measurement sensor.

[0058] In the above strain rod, the deformation of the strain rod mainly manifests itself in forces in two directions, one of which is the force in the axial direction of the strain rod, which mainly causes the length of the strain rod to change, which is manifested in the axial strain of the strain rod; the other is the force in the lateral direction, that is, the radial force of the strain rod, which mainly causes the strain rod to bend, which is manifested in the bending strain of the strain rod.

[0059] More specifically, in this embodiment, a full-bridge circuit is formed by strain gauges to measure the axial strain values of each strain rod by measuring the resistance change rate. By symmetrically arranging strain gauges on each strain rod, that is, one strain gauge on the upper surface and one on the lower surface of the strain rod, the radial strain value of each strain rod is obtained by calculating the strain difference of the symmetrically arranged strain gauges. The methods for obtaining the axial strain value and the radial strain value of the strain rod are well-known techniques, and only a simple introduction is given here without further elaboration.

[0060] It can be understood that the time period to be measured refers to the unit monitoring time of the steel arch deformation during the initial support of the tunnel, which reflects the process of real-time monitoring of the steel arch deformation, and data acquisition operations are performed at each moment within the time period to be measured.

[0061] Step S200: According to the strain data corresponding to each deformation monitoring point within the time period to be measured, analyze the movement of each strain rod, and combine the physical parameter information of the strain rod to analyze the deformation conditions of different strain rods at the same deformation monitoring point, so as to obtain the deformation detection index of each strain rod at each deformation monitoring point within the time period to be measured.

[0062] By installing strain rods between the measuring points and using the strain rods as mechanical transmission elements, the displacement or deformation of the waist measuring point is converted into the axial strain or bending strain of the corresponding connected strain rod. By measuring the strain value of the strain rod and combining the geometric relationship, the deformation amount of the associated waist measuring point is deduced inversely. Based on this, the deformation analysis of each strain rod at each deformation monitoring point is mainly divided into two dimensions, namely axial and radial. For the convenience of description and understanding, this embodiment takes one strain rod as an example for illustration, as Figure 5 which shows a partial structural schematic diagram of a strain rod between a waist measuring point and a deformation monitoring point. In the figure, x represents the axial direction and y represents the radial direction.

[0063] More specifically, as Figure 6 shown, the method for obtaining the deformation detection index of each strain rod at each deformation monitoring point within the time period to be measured can be realized by steps S201 to S203.

[0064] Step S201: According to the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding stress rod, obtain the axial displacement data of each strain rod at each deformation monitoring point.

[0065] When there is an axial displacement between the deformation monitoring point connected by the strain rod and the waist measuring point, the relative displacement between the waist measuring point and the deformation monitoring point will cause an axial strain phenomenon of the strain rod. That is, through the functional expression relationship between the axial strain value of the strain rod, the axial displacement amount of the strain rod, and the length of the strain rod, the performance of the axial displacement amount when the strain rod shows an axial strain phenomenon can be solved.

[0066] Specifically, based on the product of the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding strain rod, the axial displacement data of each strain rod at each deformation monitoring point is determined.

[0067] More specifically, taking a strain rod between the left waist measuring point B and the first connection point a as an example for illustration, it can be understood that the analysis operations of deformation and displacement conditions can be carried out at each moment during the monitoring period. Here, an example of one moment is used for illustration. Furthermore, the functional relationship expression among the axial strain value of the strain rod, the axial displacement of the strain rod, and the length of the strain rod can be expressed as: , represents the axial strain value of the strain rod, represents the axial displacement data of the strain rod, represents the length data of the strain rod. Through this functional relationship expression, the axial displacement data of the strain rod can be solved. .

[0068] It should be noted that the length data of the strain rod is the inherent physical parameter data of the strain rod and can be directly obtained. The axial displacement data of the strain rod characterizes the axial displacement performance of the relative displacement between the waist measuring point and the deformation monitoring point.

[0069] Step S202: Based on the radial strain value of each strain rod at each deformation monitoring point and various physical parameters of the corresponding stress rod, the radial displacement data of each strain rod at each deformation monitoring point is obtained.

[0070] Based on a situation similar to the axial case, when there is a radial displacement between the deformation monitoring point and the waist measuring point connected by the strain rod, the bending situation between the waist measuring point and the deformation monitoring point will cause a radial bending strain phenomenon of the strain rod. That is, through the functional expression relationship among the radial strain value of the strain rod, the physical parameter data of the strain rod, and the radial displacement of the strain rod, the radial displacement performance when the strain rod shows a bending phenomenon can be solved.

[0071] Specifically, based on the product relationship and ratio relationship between the radial strain value of each strain rod at each deformation monitoring point and the diameter data and the length data, a functional calculation formula for the radial strain value is constructed, and based on the functional calculation formula, the radial displacement data of each strain rod at each deformation monitoring point is solved.

[0072] More specifically, taking a strain rod between the left waist measuring point B and the first connection point a as an example for illustration, it can be understood that the analysis operations of deformation and displacement conditions can be carried out at each moment during the monitoring period. Here, an example of one moment is used for illustration. Furthermore, the functional relationship expression among the radial strain value of the strain rod, the physical parameter data of the strain rod, and the radial displacement of the strain rod, that is, the functional calculation formula for the radial strain value can be expressed as:

[0073]

[0074] Among them, represents the radial strain value of the strain rod, represents the radial displacement data of the strain rod, represents the length data of the strain rod, represents the cross-sectional diameter of the strain rod, and the radial displacement data of the strain rod can be solved through this function calculation formula .

[0075] It should be noted that the cross-sectional diameter of the strain rod is the inherent physical parameter data of the strain rod and can be directly obtained. The radial displacement data of the strain rod characterizes the radial displacement performance of the relative bending between the waist measurement point and the deformation monitoring point.

[0076] Step S203, according to the axial displacement data and radial displacement data of each strain rod at each deformation monitoring point during the period to be measured, combined with the length data of the corresponding stress rod, obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured.

[0077] By combining the displacement performance of the strain rod in the axial and radial directions respectively, determine the position data corresponding to the deformation phenomenon of the strain rod at each corresponding deformation monitoring point at each moment. Further, by comparing the initial position and the position after the deformation phenomenon of each deformation monitoring point after the installation of the steel arch, determine the degree of deformation at the current monitoring moment.

[0078] Specifically, for any strain rod at any deformation monitoring point, taking the waist measurement point as the origin, based on the length data of the strain rod and the initial inclination angle of the strain rod, obtain the initial polar coordinates of the strain rod relative to the waist measurement point. In this embodiment, for a strain rod between the left waist measurement point B and the first connection point a, take the length data of the strain rod as the radial coordinate of the corresponding initial polar coordinates of the strain rod, and take the initial inclination angle of the strain rod as the polar angle coordinate of the corresponding initial polar coordinates of the strain rod.

[0079] According to the same method as in step S201, the axial displacement data of the strain rod at each moment during the period to be measured can be obtained, and combined with the radial coordinate of the initial polar coordinates, determine the radial coordinate of the deformation polar coordinates of the strain rod at each moment. Specifically, for any moment, take the sum value of the axial displacement data of the strain rod and the length data of the strain rod as the radial coordinate of the deformation polar coordinates of the strain rod, which can be expressed as , represents the axial displacement data of the strain rod, represents the length data of the strain rod.

[0080] In the same way as in step S202, the radial displacement data of the strain rod at each moment within the time period to be measured can be obtained. By combining the axial displacement data and the length data of the strain rod at the corresponding moment, the deformation angle of the strain rod at each moment can be determined; the sum of the deformation angle and the initial inclination angle of the strain rod is used as the polar angle coordinate of the deformation polar coordinate of the strain rod at each moment.

[0081] Specifically, for any moment, the sum of the axial displacement data and the length data of the strain rod is obtained, and the arctangent function of the ratio of the radial displacement data of the strain rod to this sum is calculated to obtain the deformation angle of the strain rod, which can be expressed as , represents the deformation angle of the strain rod, represents the axial displacement data of the strain rod, represents the radial displacement data of the strain rod, represents the length data of the strain rod, is the arctangent function. Further, the polar angle coordinate of the deformation polar coordinate of the strain rod can be expressed as , represents the initial inclination angle of the strain rod.

[0082] It can be understood that the method for obtaining the polar coordinate in this step takes the data of a strain rod between the left waist measuring point B and the first connection point a at one moment as an example for data analysis. According to the same method, the deformation polar coordinates of each strain rod corresponding to each waist measuring point at each moment within the time period to be measured can be obtained, which can be used for subsequent analysis of the deformation and torsion conditions at the positions where the strain rods of the deformation monitoring points are located.

[0083] Finally, based on the distance between the deformation polar coordinates at the end moment and the initial moment of the time period to be measured, the deformation detection index of the strain rod at the deformation monitoring point within the time period to be measured is obtained.

[0084] It can be understood that the deformation polar coordinate at the end moment of the time period to be measured represents the end position of the deformation of the deformation monitoring point during the deformation monitoring process within the time period to be measured, and the deformation polar coordinate at the initial moment within the time period to be measured represents the initial position of the deformation monitoring point during the deformation monitoring process. Through the distance distribution between the initial position and the end position, the deformation degree at each strain rod during the deformation monitoring process of the current time period to be measured can be calculated.

[0085] Specifically, taking a strain rod between the left waist measuring point B and the first connection point a as an example for illustration, the deformation polar coordinates of the strain rod at the initial moment and the end moment within the time period to be measured are respectively converted into rectangular coordinates, and then the Euclidean distance between the two rectangular coordinates is calculated to obtain the deformation detection index of the strain rod within the time period to be measured.

[0086] So far, the deformation detection index characterizes the degree of deformation of the corresponding strain rod at the position of the deformation monitoring point, which represents the possible deformation phenomenon.

[0087] Step S300: Obtain the torsional angle detection index of each deformation monitoring point during the period to be measured according to the deformation detection index and the distance distribution between each deformation monitoring point and the waist measurement point.

[0088] In the application of the steel arch, in addition to direct stress, it may also be twisted due to uneven stress on the steel arch, thus posing a safety hazard. Therefore, the double strain rods installed at the waist measurement point of the steel arch can be combined to judge the torsional deformation. The torsional amount at the position of the deformation monitoring point of the steel arch is judged by the deformation degrees corresponding to the two different strain rods at the same deformation monitoring point, so as to judge the torsional health degree of the steel arch.

[0089] As Figure 4 shown, when the steel arch is twisted, there will be a large difference in the position information of the left strain rod 1 and the right strain rod 2 after deformation analysis, and there will also be a large difference in the displacement deformation degrees corresponding to the left strain rod 1 and the right strain rod 2. By analyzing the deformation difference between different strain rods at the position of the same deformation monitoring point and combining the actual length of the steel arch between the waist measurement point and the deformation monitoring point, the deformation situation at the position of the deformation monitoring point is converted into a torsional situation, which is used to simultaneously monitor the torsional degree of each deformation monitoring point relative to the waist measurement point.

[0090] Specifically, for any deformation monitoring point, obtain the actual length between the deformation monitoring point and the waist measurement point, calculate the difference between the deformation detection indexes of the two strain rods at the same deformation monitoring point during the period to be measured to obtain the deformation difference value of the deformation monitoring point during the period to be measured; take the arctangent function value of the ratio of the deformation difference value to the actual length as the torsional angle detection index of the deformation monitoring point during the period to be measured.

[0091] It can be understood that the actual length between the deformation monitoring point and the waist measurement point is also the actual arc length of the steel arch between the deformation monitoring point and the waist measurement point. Further, taking the strain rod between the left waist measurement point B and the deformation monitoring point corresponding to the first connection point a as an example, the torsional angle detection index of the deformation monitoring point corresponding to the first connection point a during the period to be measured can be expressed as: , where represents the torsional angle detection index of the deformation monitoring point during the period to be measured, represents the deformation detection index of the left strain rod 1 at the position of the deformation monitoring point during the period to be measured, represents the deformation detection index of the right strain rod 2 at the position of the deformation monitoring point during the period to be measured, Indicates the actual length of the steel arch between the deformation monitoring point and the waist measuring point. is the inverse tangent function.

[0092] At this point, the torsion angle detection index between each deformation monitoring point and the corresponding waist measurement point during the test time period represents the torsion deformation between the deformation monitoring point and the corresponding waist measurement point.

[0093] Step S400: using the deformation detection index and the torsion angle detection index to determine the early warning situation of the tunnel steel arch deformation within the time period to be tested.

[0094] Specifically, by using the allowable deformation range and torsion angle range of the steel arch set by the tunnel engineering standards, an engineering risk warning for the initial tunnel support can be provided, thereby achieving the purpose of deformation monitoring of the steel arch for the initial tunnel support.

[0095] Based on this, the standard deformation data and standard torsion data of the tunnel steel arch deformation are obtained; according to the comparison results of the deformation detection index and the standard deformation data corresponding to each deformation monitoring point in the test time period, and the comparison results of the torsion angle detection index and the standard torsion data, the early warning of the tunnel steel arch deformation in the test time period is obtained.

[0096] It can be understood that the standard deformation data represents the maximum allowable deformation of the tunnel steel arch, that is, when the degree of deformation of the steel arch is greater than the maximum allowable deformation, the deformation of the tunnel steel arch does not meet the engineering standards. The standard torsion data represents the maximum allowable torsion angle of the tunnel steel arch, that is, when the angle of the steel arch deformation is greater than the maximum allowable deformation angle, the deformation of the tunnel steel arch does not meet the engineering standards, and both require early warnings so that relevant staff can conduct maintenance to avoid safety problems. It should be noted that the standard deformation data and standard torsion data can be directly obtained according to the engineering standards under different tunnel initial support scenarios, and will not be elaborated on here.

[0097] More specifically, when the deformation detection index corresponding to each deformation monitoring point within the time period to be tested exceeds the standard deformation data, or the torsion angle detection index exceeds the standard torsion data, an early warning of tunnel steel arch deformation within the time period to be tested is issued; when the deformation detection index corresponding to each deformation monitoring point within the time period to be tested does not exceed the standard deformation data, and the torsion angle detection index does not exceed the standard torsion data, no early warning of tunnel steel arch deformation within the time period to be tested is issued.

[0098] In summary, in this embodiment, by installing strain rods between measurement points, the displacement or deformation of the measurement points is converted into the strain value of the strain rods, and the deformation amount of the associated measurement points is deduced inversely in combination with geometric relationships, improving the measurement accuracy. Compared with the traditional total station measurement method, this method does not need to occupy the tunnel space for a long time, reduces the impact on traffic, and lowers the cost. At the same time, not only the steel arch deformation amount of the key nodes is detected, but also the torsional deformation detection of the steel arch is carried out, improving the detection dimension of the steel arch and enhancing the monitoring safety. Further, by monitoring the deformation and torsional conditions of the steel arch in real time, the problems of uneven stress and torsion of the steel arch are found in time, improving the safety of tunnel construction. This method has strong adaptability and is applicable to tunnels with different surrounding rock grades. By adjusting the layout and measurement parameters of the strain rods, it can adapt to different construction environments and requirements.

[0099] An embodiment of the present invention also provides a measurement system applicable to the deformation of the steel arch in the initial support of a tunnel, including a memory, a processor, and a computer program stored on the memory and running on the processor. When the computer program is executed by the processor, the steps of the measurement method applicable to the deformation of the steel arch in the initial support of a tunnel are implemented. Since the embodiments of the measurement method applicable to the deformation of the steel arch in the initial support of a tunnel have been described in detail, no further introduction will be given here.

[0100] The above-described embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A measurement method applicable to the deformation of the steel arch in the initial support of a tunnel, characterized in that, The method includes the following steps: Set waist measurement points at the waist of the steel arch, and set deformation monitoring points at positions adjacent to each waist measurement point; there are two strain rods between the waist measurement points and the deformation monitoring points; obtain the strain data of each strain rod relative to the waist measurement point at each deformation monitoring point during the period to be measured; According to the strain data corresponding to each deformation monitoring point during the period to be measured, analyze the movement of each strain rod, and combine the physical parameter information of the strain rod to analyze the deformation of different strain rods at the same deformation monitoring point, so as to obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured; According to the deformation detection index and the distance distribution between each deformation monitoring point and the waist measurement point, obtain the torsional angle detection index of each deformation monitoring point during the period to be measured; Use the deformation detection index and the torsional angle detection index to judge the deformation early warning situation of the tunnel steel arch during the period to be measured.

2. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 1, characterized in that, The strain data includes axial strain value and radial strain value.

3. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 2, characterized in that, The step of analyzing the movement of each strain rod according to the strain data corresponding to each deformation monitoring point during the period to be measured, and combining the physical parameter information of the strain rod to analyze the deformation of different strain rods at the same deformation monitoring point, so as to obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured specifically includes: According to the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding stress rod, obtain the axial displacement data of each strain rod at each deformation monitoring point; According to the radial strain value of each strain rod at each deformation monitoring point and the physical parameters of the corresponding stress rod, obtain the radial displacement data of each strain rod at each deformation monitoring point; According to the axial displacement data and radial displacement data of each strain rod at each deformation monitoring point during the period to be measured, and combining the length data of the corresponding stress rod, obtain the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured.

4. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 3, characterized in that, The step of obtaining the axial displacement data of each strain rod at each deformation monitoring point according to the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding stress rod specifically includes: Based on the product of the axial strain value of each strain rod at each deformation monitoring point and the length data of the corresponding strain rod, determine the axial displacement data of each strain rod at each deformation monitoring point.

5. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 3, characterized in that, The step of obtaining the radial displacement data of each strain rod at each deformation monitoring point according to the radial strain value of each strain rod at each deformation monitoring point and the physical parameters of the corresponding stress rod specifically includes: Based on the ratio relationship between the product relationship between the radial strain value of each strain rod at each deformation monitoring point and the diameter data and the length data, construct a function calculation formula for the radial strain value, and solve the radial displacement data of each strain rod at each deformation monitoring point based on the function calculation formula.

6. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 3, characterized in that, The step of obtaining the deformation detection index of each strain rod at each deformation monitoring point during the period to be measured according to the axial displacement data and radial displacement data of each strain rod at each deformation monitoring point during the period to be measured, and combining the length data of the corresponding stress rod specifically includes: For any strain rod at any deformation monitoring point, with the waist measurement point as the origin, based on the length data of the strain rod and the initial inclination angle of the strain rod, obtain the initial polar coordinates of the strain rod relative to the waist measurement point; Obtain the axial displacement data of the strain rod at each moment within the measurement period to be measured, and combine with the radial coordinate of the initial polar coordinates to determine the radial coordinate of the deformation polar coordinates of the strain rod at each moment; Obtain the radial displacement data of the strain rod at each moment within the measurement period to be measured, and combine with the axial displacement data and length data of the strain rod at the corresponding moment to determine the deformation angle of the strain rod at each moment; use the sum value of the deformation angle and the initial inclination angle of the strain rod as the polar angle coordinate of the deformation polar coordinates of the strain rod at each moment; Based on the distance between the deformation polar coordinates at the end moment and the initial moment of the measurement period to be measured, obtain the deformation detection index of the strain rod at the deformation monitoring point within the measurement period to be measured.

7. The measuring method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 3, characterized in that, The method of obtaining the torsion angle detection index of each deformation monitoring point within the measurement period to be measured according to the deformation detection index and the distance distribution between each deformation monitoring point and the waist measurement point specifically includes: For any deformation monitoring point, obtain the actual length between the deformation monitoring point and the waist measurement point, calculate the difference between the deformation detection indexes of two strain rods at the same deformation monitoring point within the measurement period to be measured to obtain the deformation difference value of the deformation monitoring point within the measurement period to be measured; use the arctangent function value of the ratio of the deformation difference value to the actual length as the torsion angle detection index of the deformation monitoring point within the measurement period to be measured.

8. The measurement method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 7, characterized in that, The method of using the deformation detection index and the torsion angle detection index to judge the deformation early warning situation of the tunnel steel arch within the measurement period to be measured specifically includes: Obtain the standard deformation data and standard torsion data of the tunnel steel arch deformation; according to the comparison results between the deformation detection index corresponding to each deformation monitoring point within the measurement period to be measured and the standard deformation data, and the comparison results between the torsion angle detection index and the standard torsion data, obtain the deformation early warning situation of the tunnel steel arch within the measurement period to be measured.

9. The measurement method applicable to the deformation of the steel arch in the initial support of a tunnel according to claim 1, characterized in that, The method of obtaining the deformation early warning situation of the tunnel steel arch within the measurement period to be measured according to the comparison results between the deformation detection index corresponding to each deformation monitoring point within the measurement period to be measured and the standard deformation data, and the comparison results between the torsion angle detection index and the standard torsion data specifically includes: When the deformation detection index corresponding to each deformation monitoring point within the measurement period to be measured exceeds the standard deformation data, or the torsion angle detection index exceeds the standard torsion data, conduct deformation early warning of the tunnel steel arch within the measurement period to be measured; when the deformation detection index corresponding to each deformation monitoring point within the measurement period to be measured does not exceed the standard deformation data, and the torsion angle detection index does not exceed the standard torsion data, do not conduct deformation early warning of the tunnel steel arch within the measurement period to be measured.

10. A measurement system applicable to the deformation of the steel arch in the initial support of a tunnel, comprising a memory, a processor, and a computer program stored on the memory and running on the processor, characterized in that, When the computer program is executed by a processor, it implements the steps of the measurement method for the deformation of the tunnel initial support steel arch according to any one of claims 1-9.

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