A real-time monitoring method for the joint of secondary lining template

Abstract

The invention discloses a real-time monitoring method for the joints of secondary lining formworks. Before pouring secondary lining concrete, two ends of a plurality of bow strain gauges are respectively arranged on a cast structure and an adjacent secondary lining formwork; the plurality of bow strain gauges are all connected to a static strain testing system; the secondary lining concrete is poured, and during the pouring process, numerical changes of the plurality of bow strain gauges are observed, and the area where the bow strain gauge with the largest numerical change is located is reinforced; the invention arranges a bow strain gauge with one end high and the other end low on the cast structure and the secondary lining formwork, and resets the value of the bow strain gauge in this state to zero by using a static strain testing system, and during the pouring process, observes numerical changes of the plurality of bow strain gauges, and reinforces the area where the bow strain gauge with the largest numerical change is located is located, so as to avoid the occurrence of misalignment between the secondary lining structure and the short side wall and between adjacent secondary lining plates.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, and in particular to a real-time monitoring method for a second lining template joint. Background Art

[0002] The secondary lining of a tunnel is the last barrier to protect the tunnel. At present, the research on the secondary lining defects in China mainly focuses on the insufficient thickness of the secondary lining, the voids in the secondary lining, and the voids behind the secondary lining. The construction of the secondary lining mainly studies whether the concrete of the secondary lining arch is saturated and filled to prevent voids. However, further research is needed on the misalignment of the secondary lining.

[0003] As an important support method for tunnels, secondary lining needs to be built as soon as possible after tunnel excavation and support to prevent the surrounding rock from being exposed for too long, which may cause weathering, loosening and collapse. As a permanent exposed structure of tunnel engineering, the stagger control is a concentrated embodiment of construction refinement and standardization, which is related to the overall image of the tunnel. Stagger is an important reason affecting the flatness of the secondary lining wall.

[0004] At present, the protective measures for misalignment are mostly limited to the reinforcement of the formwork structure itself or the reinforcement of the connectors and anchor rods. However, the selection of the reinforcement position can only be observed by human eyes or experience, and then reinforcement is carried out. This method may lead to inaccurate selection of the position to be reinforced on the one hand, and untimely discovery of the position to be reinforced on the other hand, resulting in leakage or untimely remediation.

[0005] In order to solve the above problems, the present invention provides a real-time monitoring method for the joints of secondary lining templates to solve the problem of poor control of misalignment in existing secondary lining construction. Summary of the invention

[0006] The purpose of the present invention is to provide a real-time monitoring method for the joints of secondary lining templates, so as to improve the construction efficiency and structural stability.

[0007] To achieve the above object, the present invention provides the following solutions:

[0008] A real-time monitoring method for the joints of a secondary lining template comprises the following steps:

[0009] Before pouring the secondary lining concrete, the two ends of a number of bow strain gauges are respectively arranged on the poured structure and the adjacent secondary lining formwork in a manner of one end being high and the other end being low;

[0010] Connecting the plurality of bow strain gauges to a static strain testing system and returning the bow strain gauges to zero;

[0011] The second lining concrete is poured, and during the pouring process, the value changes of the plurality of bow strain gauges are observed and the area where the bow strain gauge with the largest value change among the plurality of bow strain gauges is located is reinforced.

[0012] Preferably, the cast structure includes a short side wall and a completed secondary lining structure. Before pouring concrete for the secondary lining, a number of bow strain gauges are arranged in sequence along the tunnel direction at the joints between the secondary lining formwork and the short side wall, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the short side wall; a number of bow strain gauges are arranged in sequence along the circumference of the secondary lining structure at the joints between the secondary lining formwork and the adjacent completed secondary lining structure, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the adjacent completed secondary lining structure.

[0013] Preferably, the plurality of bow-shaped strain gauges disposed at the joints between the secondary lining formwork and the short side wall are evenly arranged along the direction of the tunnel, with a spacing of 1 m to 2 m.

[0014] Preferably, a plurality of bow-shaped strain gauges disposed at the joint between the secondary lining template and the adjacent completed secondary lining structure are evenly arranged along the circumference of the secondary lining structure, and the number of the arranged strain gauges is not less than three.

[0015] Preferably, the value changes of the plurality of bow strain gauges are observed every fifteen to twenty minutes.

[0016] Preferably, the measure for reinforcing the area where the bow strain gauge with the largest change value is located is to tighten the screw in the area.

[0017] Preferably, the static strain testing system is of type YSV8320 ​​and has no less than 18 interfaces for connecting bow strain gauges.

[0018] Preferably, rubber fixing blocks are provided at both ends of the bow strain gauge.

[0019] Compared with the prior art, the present invention has achieved the following technical effects:

[0020] 1. The present invention arranges a bow-shaped strain gauge with one end high and the other end low on the poured structure and the secondary lining formwork, and resets the value of the bow-shaped strain gauge in this state to zero by using a static strain test system. During the pouring process, the value changes of several bow-shaped strain gauges are observed, and the area where the bow-shaped strain gauge with the largest value change is located is reinforced, so as to avoid the occurrence of misalignment between the secondary lining structure and the short side wall and between adjacent secondary lining plates.

[0021] 2. The cast structure in the present invention includes a short side wall and a completed secondary lining structure. Before pouring concrete for the secondary lining, a plurality of bow strain gauges are sequentially arranged at the joints between the secondary lining formwork and the short side wall along the tunnel direction, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the short side wall; a plurality of bow strain gauges are sequentially arranged at the joints between the secondary lining formwork and the adjacent completed secondary lining structure along the circumference of the secondary lining structure, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the adjacent completed secondary lining structure; since the positions prone to misalignment are mainly concentrated at the joints between the secondary lining structure and the short side wall and the joints between adjacent secondary lining structure plates, the concentrated arrangement of bow strain gauges at these positions can more quickly and accurately determine the positions to be reinforced and avoid the occurrence of misalignment.

[0022] 3. In the present invention, a plurality of bow-shaped strain gauges arranged at the joints between the secondary lining formwork and the low side wall are evenly arranged along the direction of the tunnel, and the spacing is 1m to 2m; the evenly arranged bow-shaped strain gauges can evenly monitor the joint area of ​​the entire low side wall and the secondary lining formwork, avoiding the problem of individual areas not being able to be monitored due to the concentrated arrangement of the bow-shaped strain gauges, resulting in misalignment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0024] Attached Figure 1 It is a schematic diagram of the arrangement of the bow strain gauge of the present invention;

[0025] Attached Figure 2 It is a schematic diagram of the enlarged view of point A;

[0026] Attached Figure 3 It is a schematic diagram of the enlarged view of point B;

[0027] Among them, 1. Second lining formwork; 2. Low side wall; 3. Nearly completed second lining structure; 4. Bow strain gauge. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] The purpose of the present invention is to provide a real-time monitoring method for the joints of secondary lining templates, so as to improve the construction efficiency and structural stability.

[0030] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] refer to Figure 1 A real-time monitoring method for the joints of a secondary lining formwork comprises the following steps: before pouring the secondary lining concrete, the two ends of a plurality of bow strain gauges 4 are respectively arranged on the cast structure and the adjacent secondary lining formwork 1 in a manner of one end being high and the other end being low; the plurality of bow strain gauges 4 are all connected to a static strain testing system, and the bow strain gauges are reset to zero; the secondary lining concrete is poured, and during the pouring process, the numerical changes of the plurality of bow strain gauges 4 are observed, and the area where the bow strain gauges 4 with the largest numerical changes are located is reinforced; the present invention avoids the occurrence of misalignment between the secondary lining structure and the short side wall 2 and between adjacent secondary lining plates by arranging a bow strain gauge 4 with one end being high and the other end being low on the cast completed structure and the secondary lining formwork 1, and by using a static strain testing system to reset the value of the bow strain gauges 4 in this state to zero, and during the pouring process, the numerical changes of the plurality of bow strain gauges 4 are observed, and the area where the bow strain gauges 4 with the largest numerical changes are located is reinforced.

[0032] refer to Figures 1 to 3 The cast structure includes a short side wall and a completed secondary lining structure. Before pouring concrete for the secondary lining, a number of bow strain gauges 4 are sequentially arranged at the joints between the secondary lining formwork 1 and the short side wall 2 along the tunnel direction, and the two ends of the bow strain gauge 4 are respectively arranged on the secondary lining formwork 1 and the short side wall 2; a number of bow strain gauges 4 are sequentially arranged at the joints between the secondary lining formwork 1 and the adjacent completed secondary lining structure 3 along the circumference of the secondary lining structure, and the two ends of the bow strain gauge 4 are respectively arranged on the secondary lining formwork 1 and the adjacent completed secondary lining structure 3; since the positions where misalignment is prone to occur are mainly concentrated at the joints between the secondary lining structure and the short side wall and the joints between adjacent secondary lining structure plates, therefore, the concentrated arrangement of bow strain gauges at this position can more quickly and accurately determine the position to be reinforced and avoid the occurrence of misalignment.

[0033] Furthermore, a number of bow-shaped strain gauges 4 arranged at the joint between the secondary lining formwork 1 and the low side wall 2 are evenly arranged along the direction of the tunnel, with a spacing of 1m to 2m; the evenly arranged bow-shaped strain gauges 4 can evenly monitor the joint area of ​​the entire low side wall and the secondary lining formwork 1, avoiding the problem of individual areas not being able to be monitored due to the concentrated setting of the bow-shaped strain gauges 4, resulting in misalignment.

[0034] Furthermore, a number of bow-shaped strain gauges 4 arranged at the joint between the secondary lining formwork 1 and the adjacent completed secondary lining structure 3 are evenly arranged along the circumference of the secondary lining structure, and the number of arrangements is not less than three; the evenly arranged bow-shaped strain gauges 4 can evenly monitor the joint area of ​​the completed secondary lining structure and the secondary lining formwork 1, avoiding the problem of individual areas not being able to be monitored due to the concentrated arrangement of the bow-shaped strain gauges 4, resulting in misalignment.

[0035] Furthermore, the numerical changes of several bow strain gauges are observed every fifteen to twenty minutes.

[0036] Furthermore, the measure for reinforcing the area where the bow strain gauge 4 with the largest change value is located is to tighten the screw in the area.

[0037] Furthermore, the static strain test system is of the YSV8320 ​​type and has no less than 18 interfaces for connecting the bow strain gauge 4 .

[0038] Furthermore, rubber fixing blocks are provided at both ends of the bow strain gauge 4 .

[0039] Adaptive changes made according to actual needs are all within the protection scope of the present invention.

[0040] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A real-time monitoring method for the joints of the secondary lining template, It is characterized in that The following steps are involved: Before pouring the secondary lining concrete, the two ends of a plurality of bow strain gauges are respectively arranged on the poured structure and the adjacent secondary lining formwork in a manner of one end being high and the other end being low; Connecting the plurality of bow strain gauges to a static strain testing system and returning the bow strain gauges to zero; The second lining concrete is poured, and during the pouring process, the value changes of the plurality of bow strain gauges are observed and the area where the bow strain gauge with the largest value change among the plurality of bow strain gauges is located is reinforced.

2. A real-time monitoring method for the joint of the secondary lining template according to claim 1, It is characterized in that The cast structure includes a short side wall and a completed secondary lining structure. Before pouring concrete for the secondary lining, a plurality of bow strain gauges are sequentially arranged at the joints between the secondary lining formwork and the short side wall along the tunnel direction, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the short side wall; a plurality of bow strain gauges are sequentially arranged at the joints between the secondary lining formwork and the completed secondary lining structure along the circumference of the secondary lining structure, and the two ends of the bow strain gauge are respectively arranged on the secondary lining formwork and the completed secondary lining structure.

3. A real-time monitoring method for the joint of the secondary lining template according to claim 2, It is characterized in that The plurality of bow-shaped strain gauges arranged at the joints between the second lining formwork and the short side wall are evenly arranged along the direction of the tunnel, with a spacing of 1m to 2m.

4. A real-time monitoring method for the joint of the secondary lining template according to claim 2, It is characterized in that A plurality of bow-shaped strain gauges arranged at the joint between the secondary lining template and the adjacent completed secondary lining structure are evenly arranged along the circumference of the secondary lining structure, and the number of the arranged strain gauges is not less than three.

5. A real-time monitoring method for the joint of the secondary lining template according to claim 1, It is characterized in that The value changes of the bow strain gauges are observed every fifteen to twenty minutes.

6. A real-time monitoring method for the joint of the secondary lining template according to claim 1, It is characterized in that The measure for reinforcing the area where the bow strain gauge with the largest change value is located is to tighten the screw in this area.

7. A real-time monitoring method for the joint of the secondary lining template according to claim 1, It is characterized in that The static strain testing system is of the YSV8320 ​​type and has no less than 18 interfaces for connecting bow strain gauges.

8. A real-time monitoring method for the joint of the secondary lining template according to claim 7, It is characterized in that Both ends of the bow strain gauge are provided with rubber fixing blocks.

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