Tunnel full-life safety monitoring system based on impedance strain effect and construction method

Abstract

The application relates to a tunnel full-life safety monitoring system based on an impedance strain effect, which comprises a monitoring system and terminal monitoring equipment; the monitoring system comprises an anchor rod piezoelectric monitoring module, a lining piezoelectric monitoring module, a ring piezoelectric monitoring module, a longitudinal Z-shaped piezoelectric axial force monitoring module and a longitudinal piezoelectric temperature monitoring module; the anchor rod piezoelectric monitoring modules are uniformly distributed in the surrounding rock; the lining piezoelectric monitoring module is laid on a lining reinforcement cage; the ring piezoelectric monitoring module is uniformly laid in a ring shape on the inner wall of the tunnel; the longitudinal Z-shaped piezoelectric axial force monitoring module is laid in a Z shape along the surface of the inner wall of the tunnel; the longitudinal piezoelectric temperature monitoring module is laid on the surface of the inner wall of the tunnel and is spaced apart from the longitudinal Z-shaped piezoelectric axial force monitoring module; and the above-mentioned five modules are electrically connected with the terminal monitoring equipment. The system comprehensively monitors the safety of the tunnel and realizes continuous monitoring of the whole tunnel.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel monitoring, in particular to a tunnel full-life safety monitoring system based on impedance strain effect and a construction method of the tunnel full-life safety monitoring system based on impedance strain effect. BACKGROUND

[0002] Tunnel is an important large infrastructure, which has great significance for improving the technical state of highway, shortening the running distance, improving the transportation capacity and the safety of vehicle driving. With the continuous expansion of the scale of tunnel construction and the extension of service time in China, the tunnel structure safety monitoring technology is also developing. At present, the tunnel monitoring mainly adopts traditional measurement method and various sensor monitoring technologies.

[0003] However, the existing tunnel monitoring technology still has some deficiencies: first, although the distributed optical fiber technology based on Brillouin scattering performs well in monitoring accuracy, sensing distance and anti-electromagnetic interference, the strain measurement range of the optical fiber is only 2%, and the demodulator is expensive, which limits its wide application; second, although the coaxial cable based on time domain reflection technology can determine the position of the sliding surface, it cannot accurately measure the moving direction and displacement of the landslide; third, the existing monitoring system is mainly point monitoring, which is difficult to realize continuous monitoring of the whole section and length of the tunnel, and cannot fully grasp the health status of the tunnel structure; fourth, as a concealed project, the internal structure health status of the tunnel is difficult to directly observe, especially for the tunnel with a length of several kilometers to several tens of kilometers, facing complex geological problems, the overall monitoring safety is extremely challenging; finally, the design life of the tunnel is 100 years, and the service life of the existing monitoring system and the convenience of replacing the aging and damaged sensors also face severe challenges.

[0004] Therefore, it is urgent to develop an economic and efficient method to realize real-time and fine monitoring and early warning of the whole life cycle of the tunnel, so as to improve the safety and reliability of the tunnel. SUMMARY

[0005] In order to solve the problems of high operation cost, low measurement accuracy and poor long-term stability of the traditional tunnel deformation monitoring system, realize the safety monitoring of the whole life cycle of the tunnel, and provide a tunnel full-life safety monitoring system based on impedance strain effect.

[0006] The application is accomplished by adopting the following technical scheme: a tunnel full-life safety monitoring system based on impedance strain effect, comprising a monitoring system and a terminal monitoring device, the monitoring system comprising an anchor rod piezoelectric monitoring module, a lining piezoelectric monitoring module, a ring piezoelectric monitoring module, a longitudinal Z-shaped piezoelectric axial force monitoring module and a longitudinal piezoelectric temperature monitoring module, the anchor rod piezoelectric monitoring module being uniformly distributed in the surrounding rock, the lining piezoelectric monitoring module being laid on the lining reinforcement cage, the ring piezoelectric monitoring module being uniformly laid in a ring shape on the inner wall of the tunnel, the longitudinal Z-shaped piezoelectric axial force monitoring module being laid in a Z shape along the surface of the inner wall of the tunnel, the longitudinal piezoelectric temperature monitoring module being laid on the surface of the inner wall of the tunnel and being spaced apart from the longitudinal Z-shaped piezoelectric axial force monitoring module, and the anchor rod piezoelectric monitoring module, the lining piezoelectric monitoring module, the ring piezoelectric monitoring module, the longitudinal Z-shaped piezoelectric axial force monitoring module and the longitudinal piezoelectric temperature monitoring module all being electrically connected with the terminal monitoring device.

[0007] Further, the longitudinal Z-shaped piezoelectric axial force monitoring module comprises a plurality of distributed piezoelectric geocables, each distributed piezoelectric geocable being arranged in a longitudinal direction along the surface of the inner wall of the tunnel by a clamp fixture, and the distributed piezoelectric geocables being distributed in a Z shape, the terminal monitoring device receiving information of the longitudinal Z-shaped piezoelectric axial force monitoring module in real time, monitoring the relative deformation between lining segments and the direction and value of the overall shape of the tunnel; the longitudinal piezoelectric temperature monitoring module comprises a plurality of distributed piezoelectric geocables, the distributed piezoelectric geocables being arranged in a longitudinal direction along the tunnel by a clamp fixture, the distributed piezoelectric geocables being spaced apart between the longitudinal Z-shaped piezoelectric axial force monitoring modules, and the terminal monitoring device continuously receiving monitoring information of the overall temperature of the tunnel and the temperature of the structural joints.

[0008] Further, the ring piezoelectric monitoring module comprises a plurality of distributed piezoelectric geocables, the distributed piezoelectric geocables being arranged along the ring line of the inner wall of the tunnel by a clamp fixture, the ring piezoelectric monitoring module monitoring the ring deformation of the tunnel in real time, and the terminal monitoring device continuously collecting and analyzing monitoring data.

[0009] Further, the anchor rod piezoelectric monitoring module comprises a plurality of anchor rod piezoelectric components, the plurality of anchor rod piezoelectric components being uniformly distributed in the thickness direction of the surrounding rock, the anchor rod piezoelectric component comprising an anchor rod and a distributed piezoelectric geocable, the distributed piezoelectric geocable being arranged along the entire anchor rod by a reinforcement-cable fixture, and the terminal monitoring device monitoring the deformation of the surrounding rock and its distribution, the internal force change and distribution of the anchor rod in real time through the anchor rod piezoelectric monitoring module.

[0010] Further, the lining piezoelectric monitoring module comprises a plurality of distributed piezoelectric geocables, the distributed piezoelectric geocables are bound on the longitudinal reinforcement of the lining reinforcement cage through the steel cable fixer, one distributed piezoelectric geocable is arranged on each longitudinal reinforcement, and the terminal monitoring equipment monitors the stress and strain of the lining through the lining piezoelectric monitoring module.

[0011] Further, the distributed piezoelectric geocable comprises a piezoelectric geocable, a multi-core wire and a high-strength glass fiber cloth, the piezoelectric geocable comprises a piezoelectric geocable positive electrode, a piezoelectric geocable negative electrode and a PE sheath, the piezoelectric geocable positive electrode and the piezoelectric geocable negative electrode are packaged in the PE sheath, two of the multi-core wires are welded with the piezoelectric geocable positive electrode and the piezoelectric geocable negative electrode respectively, the piezoelectric geocable and the multi-core wire are sewn in the high-strength glass fiber cloth, and the inner and outer surfaces of the high-strength glass fiber cloth are smeared with an adhesive.

[0012] Further, the monitoring system further comprises a traffic accident monitoring and protection module, the traffic accident monitoring and protection module comprises a piezoelectric monitoring net and a gradient energy absorption layer, the piezoelectric monitoring net is installed close to the inner wall of the tunnel on the inner side, the gradient energy absorption layer is fixedly installed on the outer side of the piezoelectric monitoring net, the gradient energy absorption layer comprises a damping energy absorption layer and a structural energy absorption layer, the damping energy absorption layer is installed between the structural energy absorption layer and the piezoelectric monitoring net, the piezoelectric monitoring net comprises a plurality of distributed piezoelectric geocables and a grid frame, the distributed piezoelectric geocables are bound on the grid frame in a net shape, and the distributed piezoelectric geocables are electrically connected with the terminal monitoring equipment.

[0013] Further, the structural energy absorption layer comprises a plurality of composite energy absorption components, the plurality of composite energy absorption components are uniformly arranged on the outer side of the damping energy absorption layer, the composite energy absorption component comprises a surface layer, a honeycomb structure and a plurality of shape memory alloy support rods, the plurality of shape memory alloy support rods are fixed between the surface layer and the damping energy absorption layer, the plurality of shape memory alloy support rods are distributed in a circumferential array along the edge of the surface layer, and the honeycomb structure is fixed at the middle between the surface layer and the damping energy absorption layer.

[0014] Further, the damping energy absorption layer comprises a plurality of dampers and a separation layer, the plurality of dampers are uniformly distributed between the structural energy absorption layer and the piezoelectric monitoring net, the separation layer is fixed on the top of the damper, and the bottom of the composite energy absorption component is fixed on the separation layer.

[0015] Further, the piezoelectric monitoring net comprises a plurality of distributed piezoelectric geocables and a grid frame, the distributed piezoelectric geocables are bound on the grid frame in a net shape, and the distributed piezoelectric geocables are electrically connected with the terminal monitoring equipment.

[0016] Further, a construction method of a tunnel full-life safety monitoring system based on impedance strain effect is provided, and the steps are as follows:

[0017] 1) Preparation of distributed piezoelectric geocable,

[0018] Two sensing wires in the multi-core wire are welded with the positive electrode of the piezoelectric geocable and the negative electrode of the piezoelectric geocable. Then, they are installed in the high-strength glass fiber fabric in which the sewing thread is sewn, and finally, an adhesive is added at the installation position;

[0019] 2) Piezoelectric monitoring module of anchor rod,

[0020] Before the construction of the anchor rod, the distributed piezoelectric geocable is fixed to the anchor rod in the longitudinal direction by the steel-cable fixer, so that the anchor rod is basically attached to the high-strength glass fiber fabric. The initial strain state of the piezoelectric geocable is obtained by using the data processing module, the arrangement is completed, and the next step of the construction of the anchor rod is performed;

[0021] 3) Piezoelectric monitoring module of lining,

[0022] Before the binding of the reinforcement cage of the lining and the secondary lining, the piezoelectric geocable of the lining is fixed to the longitudinal reinforcement of the lining reinforcement cage by the steel-cable fixer, so that the longitudinal reinforcement of the lining reinforcement cage is basically attached to the high-strength glass fiber fabric. The binding work of the reinforcement cage of the lining reinforcement cage stirrup is performed, after the completion, the initial strain state of the piezoelectric geocable of the lining is obtained by using the data processing module, the arrangement is completed, and the next step of the construction of the lining is performed;

[0023] 4) Piezoelectric monitoring module of ring,

[0024] At the position where the ring piezoelectric geocable needs to be installed, the surface of the lining is wiped clean, and along the tunnel section, every meter from the middle of the tunnel to both sides, the expansion anchor is driven into the tunnel inner wall, and at the same time, the clamp is installed on the anchor. The ring piezoelectric geocable is installed, the screw is tightened, the arrangement of the piezoelectric geocable at the ring position is completed, and after the completion, the initial strain state of the piezoelectric geocable is obtained by using the data processing module, the arrangement is completed;

[0025] 5) Piezoelectric axial force monitoring module of longitudinal Z-shaped,

[0026] It comprises a plurality of distributed piezoelectric geocables. When each distributed piezoelectric geocable is installed, the installation height is determined, and then two rows of expansion anchors are driven into the tunnel inner wall along the longitudinal direction of the tunnel. The first row of expansion anchors is driven in according to the same spacing, and the second row of expansion anchors is distributed according to the same spacing and is located below the gap between the two expansion anchors of the previous row. A clamp is arranged on each expansion anchor, and the distributed piezoelectric geocable is fixed on the first row of expansion anchors and the second row of expansion anchors in sequence and at intervals by screws to form a Z-shaped distribution. In this way, all the distributed piezoelectric geocables are installed in the Z-shaped manner on the tunnel inner wall, and after the completion, the initial strain state of the Z-shaped longitudinal piezoelectric axial force monitoring geocable 6 is obtained by using the data processing module, and the arrangement is completed.

[0027] 6) longitudinal piezoelectric temperature monitoring module,

[0028] First, determine the height of the installation on the inner wall of the tunnel, along the longitudinal direction of the inner wall of the tunnel, every certain distance, drill into the expansion anchor, at the same time, install the clamp on the expansion anchor in turn, then put into the distributed piezoelectric geotextile cable, tighten the screw, complete the installation, finally use the data processing module to obtain the initial strain state of the longitudinal piezoelectric temperature monitoring module, complete the arrangement.

[0029] The beneficial effects of the present application are:

[0030] The present application realizes the mechanical characteristics of surrounding rock deformation and its distribution law, anchor internal force and its distribution law, relative deformation between lining segments, overall deformation of the tunnel, ring deformation of the tunnel and temperature characteristics for feedback leakage problems and fire prevention problems by means of distributed piezoelectric geotextile sensing means. The key positions of the tunnel safety are comprehensively monitored, and through the optimization of the laying design and construction of the distributed piezoelectric cable, the wiring complexity is reduced, the flexibility and expansibility are improved, and the continuous monitoring of the whole length of the tunnel is realized.

[0031] The distributed piezoelectric geotextile cable includes a piezoelectric geotextile cable, a multi-core wire and a high-strength glass fiber cloth, the piezoelectric geotextile cable signal is transmitted through the multi-core wire, the high-strength glass fiber cloth effectively improves the damage resistance of the piezoelectric geotextile cable and the multi-core wire, has the characteristics of high temperature resistance, can ensure the normal use of the monitoring system in case of fire, has the characteristics of light and soft, is convenient for sticking and fixing, and the gap of the fiber cloth provides a high-quality channel for the adhesive, improves the compactness of the sticking. The present application has higher measurement accuracy, better long-term stability and lower operation cost, and can meet the demand of tunnel safety monitoring in the whole life cycle. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a structural schematic diagram of the tunnel whole life safety monitoring system based on impedance strain effect;

[0033] Figure 2 It is a flow chart of the tunnel whole life safety monitoring system based on impedance strain effect;

[0034] Figure 3 It is a local structure schematic diagram of the distributed piezoelectric geotextile cable;

[0035] Figure 4 It is a structure schematic diagram of the clamp fixer;

[0036] Figure 5 It is a structure schematic diagram of the anchor piezoelectric monitoring module;

[0037] Figure 6Structure diagram of lining piezoelectric monitoring module;

[0038] Figure 7 Structure diagram of annular piezoelectric monitoring module;

[0039] Figure 8 Structure diagram of longitudinal Z-shaped piezoelectric axial force monitoring module;

[0040] Figure 9 Structure diagram of longitudinal piezoelectric temperature monitoring module;

[0041] Figure 10 Structure diagram of steel bar-cable fixer;

[0042] Figure 11 Structure diagram of traffic accident monitoring and protection module in the second embodiment;

[0043] Figure 12 Structure diagram of local section of traffic accident monitoring and protection module;

[0044] Figure 13 Structure diagram of local section of piezoelectric monitoring network.

[0045] Reference signs: terminal monitoring device 1, anchor rod piezoelectric monitoring module 2, lining piezoelectric monitoring module 3, annular piezoelectric monitoring module 4, longitudinal Z-shaped piezoelectric axial force monitoring module 5, longitudinal piezoelectric temperature monitoring module 6, distributed piezoelectric geocable 7, clamp fixer 8, traffic accident monitoring and protection module 9, steel bar-cable fixer 10, information acquisition and transmission module 11, data processing module 12, solar panel 13, warning light 14, terminal computer 15, terminal mobile device 16, tunnel 20, anchor rod 21, longitudinal reinforcement of lining reinforcement cage 31, piezoelectric geocable 71, multi-core wire 72 high-strength glass fiber cloth 73, positive electrode of piezoelectric geocable 711, negative electrode of piezoelectric geocable 712, PE sheath 713, clamp fixer 8 includes clamp 81, expansion anchor 82, screw 83, accommodating groove 84, nut 85, plastic buckle 101, hand screw 102, piezoelectric monitoring network 91, gradient energy absorption layer 92, damping energy absorption layer 921, composite energy absorption component 922, grid frame 911, surface layer 9221, honeycomb structure 9222, shape memory alloy support rod 9223, damper 9211, partition layer 9212. DETAILED DESCRIPTION

[0046] In order to further illustrate the technical means adopted by the present application and the effects achieved by the present application, the specific embodiments, structures, features and effects of the present application will be described in detail below with reference to the accompanying drawings and preferred embodiments.

[0047] REFERENCE Figures 1-5As shown, the first embodiment of the present application provides a tunnel full-life safety monitoring system based on an impedance strain effect, which comprises a monitoring system and a terminal monitoring device 1. The monitoring system comprises an anchor piezoelectric monitoring module 2, a lining piezoelectric monitoring module 3, a ring piezoelectric monitoring module 4, a longitudinal Z-shaped piezoelectric axial force monitoring module 5 and a longitudinal piezoelectric temperature monitoring module 6. The anchor piezoelectric monitoring module 2 is uniformly distributed in the surrounding rock for monitoring the deformation and distribution of the surrounding rock, as well as the internal force and distribution of the anchor. The lining piezoelectric monitoring module 3 is laid on the lining reinforcement cage for monitoring the stress and strain of the lining. The ring piezoelectric monitoring module 4 is uniformly laid on the inner wall of the tunnel in a ring shape for monitoring the ring deformation. The longitudinal Z-shaped piezoelectric axial force monitoring module 5 is laid on the inner wall surface of the tunnel in a Z-shaped manner along the inner wall surface of the tunnel for monitoring the relative deformation between the lining segments and the direction and value of the overall shape of the tunnel. The longitudinal piezoelectric temperature monitoring module 6 is laid on the inner wall surface of the tunnel and is spaced apart from the longitudinal Z-shaped piezoelectric axial force monitoring module 5 for monitoring the tunnel leakage and fire prevention. The anchor piezoelectric monitoring module 2, the lining piezoelectric monitoring module 3, the ring piezoelectric monitoring module 4, the longitudinal Z-shaped piezoelectric axial force monitoring module 5 and the longitudinal piezoelectric temperature monitoring module 6 all use a distributed piezoelectric geocable 7 as a sensor. Through different laying modes of the distributed piezoelectric geocable 7, the system can realize comprehensive monitoring of deformation, leakage and fire prevention parameters at different positions of the tunnel. The above five monitoring modules are electrically connected with the terminal monitoring device 1. After the terminal monitoring system collects information, it transmits, processes data, visualizes, monitors and warns, transmits to the terminal monitoring device and stores data according to the impedance-strain effect and piezoelectric effect. The above modules are arranged at key positions of the tunnel. Through optimization of the laying design and construction of the distributed piezoelectric cable, the system reduces the wiring complexity, improves the flexibility and expandability, reduces the possibility of problems and damage of parts, and meets the full-life monitoring of the tunnel design life of 100 years. The continuous monitoring of the full length of the tunnel is realized. This monitoring system can provide continuous data of stress, strain and temperature, helping to identify small changes and potential problems.

[0048] Specifically, the distributed piezoelectric geocable 7 comprises a piezoelectric geocable 71, a multi-core wire 72 and a high-strength glass fiber cloth 73. The piezoelectric geocable 71 comprises a piezoelectric geocable positive electrode 711, a piezoelectric geocable negative electrode 712 and a PE sheath 713, and the piezoelectric geocable positive electrode (conductive core) 711 and the piezoelectric geocable negative electrode (copper mesh) 712 are encapsulated in the PE sheath 713. Two of the multi-core wires 72 are welded with the piezoelectric geocable positive electrode 711 and the piezoelectric geocable negative electrode 712 respectively, the piezoelectric geocable 71 and the multi-core wire 72 are sewn in the high-strength glass fiber cloth 73, and the inner and outer surfaces of the high-strength glass fiber cloth 73 are coated with adhesive. The signal of the distributed piezoelectric geocable is transmitted through the multi-core wire, and the different segmented multi-core wires are 2% longer than the piezoelectric geocable. The PE sheath has the advantages of heat resistance, corrosion resistance and pressure resistance, and can play a waterproof packaging role. The high-strength glass fiber cloth 73 effectively improves the damage resistance of the piezoelectric geocable 71 and the multi-core wire 72, has the characteristics of high temperature resistance, can ensure the normal use of the monitoring system in case of fire, has the characteristics of light weight and softness, is convenient for sticking and fixing, and the voids of the fiber cloth provide a high-quality channel for the adhesive, improving the compactness of the paste. After the piezoelectric geocable is subjected to tension, the test impedance and the actual strain form a functional relationship, and the strain size can be calculated by monitoring the impedance, so as to reflect the mechanical characteristics such as the deformation of the surrounding rock and its distribution law, the internal force of the anchor rod and its distribution law, the relative deformation between the lining segments, the overall deformation of the tunnel, the circumferential deformation of the tunnel, etc. At the same time, compared with the traditional optical fiber monitoring system, the distributed piezoelectric geocable has lower cost, and the cable is not easy to break, not easy to damage, has high survival rate, low failure rate, obvious durability and long service life.

[0049] The longitudinal Z-shaped piezoelectric axial force monitoring module 5 comprises a plurality of distributed piezoelectric geocables 7, each of which is arranged along the longitudinal direction of the inner wall surface of the tunnel through the clamp holder 8, and the distributed piezoelectric geocables are distributed in a Z-shaped manner. The terminal monitoring device 1 receives the information of the longitudinal Z-shaped piezoelectric axial force monitoring module 5 in real time, monitors the relative deformation between the lining segments and the direction and value of the overall shape of the tunnel, and the module can timely identify and warn the tunnel safety problems such as excessive deformation of the tunnel and settlement of the lining segments in the tunnel.

[0050] The longitudinal piezoelectric temperature monitoring module 6 comprises a plurality of distributed piezoelectric geocables 7, which are arranged along the longitudinal direction of the tunnel through the clamp holder 8, and are distributed between the longitudinal Z-shaped piezoelectric axial force monitoring modules. The terminal monitoring device 1 continuously receives monitoring information of the overall temperature and structural joint temperature of the tunnel. After the piezoelectric geocable is subjected to temperature changes, the test impedance and the actual strain are in a functional relationship, and the strain size can be calculated by monitoring the impedance, thereby being used for the penetration and fire prevention problems of the tunnel. The overall temperature and structural joint temperature of the tunnel are monitored in real time. Through continuous acquisition and analysis of monitoring data, the module can timely identify and warn the tunnel safety problems such as leakage and fire prevention in the tunnel.

[0051] The annular piezoelectric monitoring module 4 comprises a plurality of distributed piezoelectric geocables 7, which are arranged along the inner wall ring line of the tunnel through the clamp holder 8, and the annular piezoelectric monitoring module 4 monitors the ring deformation of the tunnel in real time. The terminal monitoring device 1 continuously acquires and analyzes monitoring data. Through continuous acquisition and analysis of monitoring data, the module can timely identify and warn the tunnel safety problems such as strain and overall inclination of the tunnel ring line in the tunnel.

[0052] The anchor piezoelectric monitoring module 2 comprises a plurality of anchor piezoelectric components, which are uniformly distributed along the thickness direction of the surrounding rock. The anchor piezoelectric component comprises an anchor 21 and a distributed piezoelectric geocable 7, which is arranged along the entire anchor 21 through the steel cable holder 10. The terminal monitoring device 1 monitors the deformation of the surrounding rock and its distribution, as well as the internal force change and distribution of the anchor in real time through the anchor piezoelectric monitoring module 2. Through continuous acquisition and analysis of monitoring data, the tunnel safety problems such as excessive deformation or anchor failure in the tunnel are timely identified and warned.

[0053] The lining piezoelectric monitoring module 3 comprises a plurality of distributed piezoelectric geocables 7, which are bound on the longitudinal reinforcement 31 of the lining steel reinforcement cage through the steel cable holder 10. Each longitudinal reinforcement 31 is provided with one distributed piezoelectric geocable 7. The terminal monitoring device 1 monitors the stress and strain of the lining through the lining piezoelectric monitoring module 3. Through continuous acquisition and analysis of monitoring data, the tunnel safety problems such as stress concentration and excessive deformation in the tunnel are timely identified and warned.

[0054] The terminal monitoring device 1 comprises an information acquisition and transmission module 11, a data processing module 12 and a safety monitoring display and early warning module. The distributed piezoelectric geocable 7 is used to obtain sensing signals at various positions and wirelessly transmit them to the signal acquisition and transmission module. The signal acquisition and transmission module 11 is powered by a solar panel 13, adjusts the frequency of signal acquisition, filters through a filter, acquires signals, converts signals and transmits the obtained signals to a data processing computer. The data processing module 12 processes data according to piezoelectric effect and impedance strain effect, is responsible for wavelet denoising, screening, curve drawing and storage of collected data, can obtain surrounding rock deformation and its distribution law, lining stress and its distribution law, relative deformation between lining segments, overall deformation and circumferential strain of the tunnel and temperature information to solve the safety monitoring of leakage and fire prevention, and transmits the processed data to the safety monitoring display and early warning module. The safety monitoring display and early warning module comprises warning lights 14 and terminal equipment (including a terminal computer 15 and / or a terminal mobile device 16). The safety monitoring display and early warning module performs threshold monitoring through data visualization. If a certain item of monitoring data exceeds the threshold frequently for multiple times, the multi-stage warning lights 14 will light up warning lights of corresponding colors, i.e. blue (requiring inspection), yellow (requiring inspection and warning) and red (requiring inspection and evacuation). All visualized data is wirelessly transmitted to terminal equipment such as terminal computers 15 and servers 17 of relevant departments and terminal mobile devices 16 of relevant personnel to realize real-time visualized monitoring of tunnel safety throughout the life cycle.

[0055] The above-mentioned annular piezoelectric monitoring module 4, longitudinal Z-shaped piezoelectric axial force monitoring module 5 and longitudinal piezoelectric temperature monitoring module 6 are all installed with the distributed piezoelectric geocable 7 by means of the hand-tightening type clamp fixer 8. The clamp fixer 8 comprises a clamp 81, an expansion anchor 82 and a screw 83. One side of the clamp 81 is mounted on the expansion anchor 82. The clamp 81 is provided with a receiving groove 84 for accommodating the piezoelectric geocable. The other side of the clamp is adjustably connected with the screw 83. The clamp is provided with a threaded hole matched with the screw. The adjustment end of the screw extends into the receiving groove 84 through the threaded hole. The clamp 81 and the expansion anchor 82 are detachably connected. A matched nut 85 is arranged on one side of the clamp. One end of the expansion anchor 82 is threadedly connected with the nut. The specific use method comprises the following steps: driving the anchor 82 into the tunnel inner wall where the clamp needs to be installed, then mounting the clamp 81 on the anchor, then sleeving the piezoelectric geocable 7 and finally tightening the screw 83 to complete the installation. The hand-tightening type clamp fixer is convenient for fixing and replacing the piezoelectric geocable 7 and achieves integrated installation of the clamp and the anchor. The expansion bolt is driven into the tunnel inner wall to fix, which is simple in operation and firm in fixation.

[0056] The anchor rod piezoelectric monitoring module 2 and the lining piezoelectric monitoring module 3 are both bound with the distributed piezoelectric geocable 7 through the steel-cable fixer 10. The steel-cable fixer 10 comprises a plastic buckle 101 and a hand screw 102. The distributed piezoelectric geocable 7 is preliminarily fixed on the steel bar or anchor rod through the plastic buckle 101, and the internal vertical lines increase the friction to prevent the cable from moving along the longitudinal direction of the steel bar. The hand screw 102 is tightened above the distributed piezoelectric geocable to further fix the cable and prevent it from rotating along the steel bar, so as to achieve the anchoring effect.

[0057] The construction method of the tunnel full-life safety monitoring system based on the impedance strain effect comprises the following steps:

[0058] 1) The distributed piezoelectric geocable 7 is prepared.

[0059] Two sensing lines in the multi-core wire 72 are welded with the positive electrode 711 and the negative electrode 712 of the piezoelectric geocable. Then, they are installed in the high-strength glass fiber woven fabric 73 in which the sewing line is sewn, and finally, the adhesive is added at the installation position.

[0060] 2) The anchor rod piezoelectric monitoring module 2.

[0061] Before the construction of the anchor rod 21, the distributed piezoelectric geocable 7 is fixed on the anchor rod 21 in the longitudinal direction through the steel-cable fixer 10, so that the anchor rod 21 is basically attached to the high-strength glass fiber woven fabric. The initial strain state of the piezoelectric geocable is obtained by using the data processing module, the arrangement is completed, and the next step of the construction of the anchor rod is performed.

[0062] 3) The lining piezoelectric monitoring module 3.

[0063] Before the steel reinforcement cage of the lining and secondary lining is bound, the lining distributed piezoelectric geocable 7 is fixed on the longitudinal reinforcement 31 of the lining steel reinforcement cage through the steel-cable fixer, so that the longitudinal reinforcement 31 of the lining steel reinforcement cage is basically attached to the high-strength glass fiber woven fabric. The steel reinforcement cage binding work with the stirrup of the lining steel reinforcement cage is performed. After the completion, the initial strain state of the lining piezoelectric geocable is obtained by using the data processing module, the arrangement is completed, and the next step of the construction of the lining is performed.

[0064] 4) The annular piezoelectric monitoring module 4.

[0065] At the position where the annular piezoelectric geocable needs to be installed, the surface of the lining is wiped clean. Along the tunnel section, the expansion anchor 82 is driven into the inner wall of the tunnel every meter from the middle of the tunnel to both sides, and the clamp 81 is installed on the anchor 82. The annular distributed piezoelectric geocable 7 is installed, the screw is tightened, and the arrangement of the piezoelectric geocable at the annular position is completed. After the completion, the initial strain state of the piezoelectric geocable is obtained by using the data processing module, and the arrangement is completed.

[0066] 5) longitudinal zigzag piezoelectric axial force monitoring module 5.

[0067] A plurality of distributed piezoelectric geocables 7 are included. When each distributed piezoelectric geocable 7 is installed, the installation height is first determined; then two rows of expansion anchors 82 are driven along the longitudinal direction of the tunnel wall in the tunnel, and a clamp is arranged on each expansion anchor. The distributed piezoelectric geocable 7 is fixed on the first row of clamps and the second row of clamps in turn and alternately through screws, forming a zigzag distribution (the first row of clamp fixers is driven according to the same spacing, the second row of clamp fixers is also distributed according to the same spacing, and is located below the gap between the two clamp fixers of the previous row, respectively); in this way, all the distributed piezoelectric geocables 7 are installed in a zigzag shape on the tunnel wall; after completion, the initial strain state of the zigzag longitudinal piezoelectric axial force monitoring geocable 6 is obtained using a data processing module, and the arrangement is completed.

[0068] 6) longitudinal piezoelectric temperature monitoring module 6,

[0069] The installation height on the tunnel wall is first determined, expansion anchors 82 are driven at regular intervals along the longitudinal direction of the tunnel wall, clamps 81 are installed on the expansion anchors 82 in turn, distributed piezoelectric geocables 7 are sleeved, and screws 83 are tightened to complete the installation. Finally, the initial strain state of the longitudinal piezoelectric temperature monitoring module is obtained using a data processing module, and the arrangement is completed.

[0070] Reference Figures 11-13 As shown in FIG. 2, the second embodiment of the present application provides a tunnel full-life safety monitoring system based on impedance strain effect, which is basically the same as the first embodiment, and the difference lies in that the monitoring system further comprises a traffic accident monitoring and protection module 9, which is preferably installed in the part of the tunnel 20 where traffic accidents are prone to occur, such as the curved section of the tunnel 20.

[0071] The traffic accident monitoring and protection module 9 comprises a piezoelectric monitoring net 91 and a gradient energy absorption layer 92. The piezoelectric monitoring net 91 is fixedly installed on the inner wall of the tunnel (which can be installed by the clamp fixer 8), and the gradient energy absorption layer 92 is fixedly installed on the outer side of the piezoelectric monitoring net. The gradient energy absorption layer 92 comprises a damping energy absorption layer 921 and a structural energy absorption layer. The damping energy absorption layer is installed between the structural energy absorption layer and the piezoelectric monitoring net. The piezoelectric monitoring net 91 is electrically connected with the terminal monitoring device 1. When a traffic accident occurs in the tunnel, the accident vehicle collides with the traffic accident monitoring and protection module in the tunnel. The gradient energy absorption layer absorbs the impact force when the vehicle collides, protects the safety of the driver and passengers, and reduces the damage to the tunnel structure. The damping energy absorption layer absorbs energy in the transverse direction (perpendicular to the direction of vehicle movement), and the structural energy absorption layer absorbs energy in the longitudinal direction (along the direction of vehicle movement). Through the synergistic effect of transverse energy absorption and longitudinal energy absorption, the forward speed is slowed down, the passengers are protected, and the lateral force is offset, and the tunnel wall is protected. While the gradient energy absorption layer absorbs most of the impact force, part of the impact force is transmitted to the piezoelectric monitoring net. The distributed piezoelectric geotextile cable on the piezoelectric monitoring net is deformed under pressure, and the signal is transmitted to the terminal monitoring device. According to the information of the terminal device, the relevant departments can obtain the information of the traffic accident in advance, and improve the processing speed and efficiency.

[0072] Specifically, the structure energy absorption layer includes a plurality of composite energy absorption components 922, which are uniformly arranged outside the damping energy absorption layer 921. The composite energy absorption component 922 includes a surface layer 9221, a honeycomb structure 9222, and a plurality of shape memory alloy support rods 9223, a plurality of shape memory alloy support rods 9223 are fixed between the surface layer 9221 and the damping energy absorption layer 9221, the plurality of shape memory alloy support rods 923 are distributed in a circumferential array along the edge of the surface layer 9221, and the honeycomb structure 9222 is fixed at the middle between the surface layer and the damping energy absorption layer 921. The surface layers 9221 between adjacent composite energy absorption components can be fixedly connected to be integrated, or have gaps between adjacent surface layers, so as to facilitate replacement of a single damaged composite energy absorption component 922. The honeycomb structure 9222 is an inclined negative Poisson's ratio honeycomb structure, which is formed by periodically arranging a plurality of negative Poisson's ratio unit structures, the negative Poisson's ratio unit structures are all arranged in an inclined shape and inclined in the direction of vehicle travel. The negative Poisson's ratio honeycomb structure has the effects of delaying damage and absorbing more energy, the inclined design further decomposes the impact force, reduces the risk of vehicle rollover, and further protects the driver and passengers. The composite energy absorption component 922 is surrounded by shape memory alloy support rods 9223, which serve as support for the surface layer when no impact occurs, and at the same time, the negative Poisson's ratio honeycomb structure 9222 is in an unfolded state (expanded state); when impact occurs, the super-elasticity of the shape memory alloy support rod 9223 absorbs part of the impact force, and when the vehicle is removed and the external force disappears, the self-resetting property of the shape memory alloy support rod 9223 restores it to its original shape, reducing the cost of manual resetting. The inner cavity of the shape memory alloy support rod is provided with a heating rod, the heating rod is connected with an external power supply through a wire, and a controller of the heating rod is electrically connected with an external terminal device or a mobile terminal device. After the accident is handled, the staff remotely controls or remotely starts the heating rod to provide the temperature required for resetting of the shape memory alloy support rod, and triggers the support rod to restore to the original state.

[0073] The damping energy absorption layer 921 includes a plurality of dampers 9211 and a partition layer 9212, the plurality of dampers 9211 are uniformly distributed between the structure energy absorption layer and the piezoelectric monitoring network 91, the partition layer 9212 is fixed on the top of the dampers 9211, and the bottom of the composite energy absorption component 922 is fixed on the partition layer 9212. The damper 9211 absorbs energy transversely, absorbs the ability perpendicular to the direction of vehicle movement, avoids the vehicle from rebounding to hit the tunnel wall again, protects the tunnel wall, absorbs the kinetic energy of the lateral deviation or rotation of the vehicle, and reduces the out-of-control rotation or rolling. The partition layer 9212 is preferably a composite layer of a honeycomb structure, has a resetting capability, deforms correspondingly when receiving external impact force, and resets with the damper when the impact force is unloaded.

[0074] The piezoelectric monitoring network 91 comprises a plurality of distributed piezoelectric geocables 7 and a grid frame 911, the distributed piezoelectric geocables are bound in a net shape on the grid frame 911, and the distributed piezoelectric geocables 7 are electrically connected with the terminal monitoring device 1. The grid frame is installed on the side wall of the tunnel section prone to accidents, the distributed piezoelectric geocable monitors the specific position of the traffic accident impact force, and transmits the accident position to the terminal device and issues a warning, the staff quickly make a judgment in combination with the nearby camera device, improve the processing speed and efficiency, and improve the efficiency of subsequent road rescue or road dredging. The traffic accident monitoring and protection module further comprises a warning screen, the warning screen is provided at different positions of the tunnel, and the warning screen is connected with the terminal monitoring device, when the piezoelectric monitoring network monitors the accident position, the terminal monitoring device sends a warning to the staff at the same time, and the warning screen adjacent to the accident section displays the distance of the accident position, prompts the rear vehicle to slow down, and avoids the occurrence of a chain accident.

[0075] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the present application, and any modification, change and modification of the above embodiment according to the technical essence of the present application are still within the scope of the present application.

Claims

1. A tunnel life-cycle safety monitoring system based on impedance strain effect, comprising a monitoring system and terminal monitoring equipment, characterized in that: The monitoring system includes an anchor bolt piezoelectric monitoring module, a lining piezoelectric monitoring module, a ring-shaped piezoelectric monitoring module, a longitudinal Z-shaped piezoelectric axial force monitoring module, a longitudinal piezoelectric temperature monitoring module, and a traffic accident monitoring and protection module. The anchor bolt piezoelectric monitoring modules are evenly distributed in the surrounding rock. The lining piezoelectric monitoring modules are laid on the lining reinforcement cage. The ring-shaped piezoelectric monitoring modules are evenly laid in a ring shape on the tunnel inner wall. The longitudinal Z-shaped piezoelectric axial force monitoring modules are laid in a Z-shape along the tunnel inner wall surface. The longitudinal piezoelectric temperature monitoring module is laid on the tunnel inner wall surface and is adjacent to the longitudinal Z-shaped piezoelectric axial force monitoring modules. The traffic accident monitoring and protection module is spaced out and includes a piezoelectric monitoring network and a gradient energy-absorbing layer. The piezoelectric monitoring network is installed close to the inner wall of the tunnel, and the gradient energy-absorbing layer is fixedly installed on the outer side of the piezoelectric monitoring network. The gradient energy-absorbing layer includes a damping energy-absorbing layer and a structural energy-absorbing layer. The damping energy-absorbing layer includes multiple dampers and partitions and is installed between the structural energy-absorbing layer and the piezoelectric monitoring network. The anchor piezoelectric monitoring module, the lining piezoelectric monitoring module, the annular piezoelectric monitoring module, the longitudinal Z-shaped piezoelectric axial force monitoring module, the longitudinal piezoelectric temperature monitoring module, and the piezoelectric monitoring network are all electrically connected to the terminal monitoring equipment. The structural energy-absorbing layer includes multiple composite energy-absorbing components, which are uniformly arranged on the outside of the damping energy-absorbing layer. Each composite energy-absorbing component includes a surface layer, a honeycomb structure, and multiple shape memory alloy support rods. Multiple shape memory alloy support rods are fixed between the surface layer and the damping energy-absorbing layer. The multiple shape memory alloy support rods are distributed in a circumferential array along the edge of the surface layer. The honeycomb structure is fixed in the middle between the surface layer and the damping energy-absorbing layer. The honeycomb structure is an inclined negative Poisson's ratio honeycomb structure, which is formed by the periodic arrangement of multiple negative Poisson's ratio unit cells. A heating rod is provided in the inner cavity of the shape memory alloy support rod.

2. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 1, characterized in that: The longitudinal Z-shaped piezoelectric axial force monitoring module includes multiple distributed piezoelectric geoclines. Each distributed piezoelectric geocline is laid out longitudinally along the inner wall surface of the tunnel through a clamp fixer, and the distributed piezoelectric geoclines are distributed in a Z-shape. The terminal monitoring device receives information from the longitudinal Z-shaped piezoelectric axial force monitoring module in real time, and monitors the relative deformation between lining segments and the direction and magnitude of the overall shape of the tunnel. The longitudinal piezoelectric temperature monitoring module includes multiple distributed piezoelectric geoclines. The distributed piezoelectric geoclines are laid out longitudinally within the tunnel through a clamp fixer. The distributed piezoelectric geoclines are spaced apart between the longitudinal Z-shaped piezoelectric axial force monitoring modules. The terminal monitoring device continuously receives monitoring information on the overall temperature of the tunnel and the temperature of the structural joints.

3. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 1 or 2, characterized in that: The annular piezoelectric monitoring module includes multiple distributed piezoelectric geoclines, which are laid out along the inner wall of the tunnel using clamps. The annular piezoelectric monitoring module monitors the circumferential deformation of the tunnel in real time, and the terminal monitoring equipment continuously collects and analyzes the monitoring data.

4. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 3, characterized in that: The anchor piezoelectric monitoring module includes multiple anchor piezoelectric components, which are evenly distributed along the thickness direction of the surrounding rock. Each anchor piezoelectric component includes an anchor and a distributed piezoelectric geocable. The distributed piezoelectric geocable is laid along the entire anchor through a steel bar-cable fastener. The terminal monitoring device monitors the deformation and distribution of the surrounding rock, as well as the changes and distribution of the internal forces of the anchor, in real time through the anchor piezoelectric monitoring module.

5. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 4, characterized in that: The lining piezoelectric monitoring module includes multiple distributed piezoelectric geocables. The distributed piezoelectric geocables are tied to the longitudinal bars of the lining reinforcement cage by steel bar-cable fasteners. Each longitudinal bar is equipped with a distributed piezoelectric geocable. The terminal monitoring equipment monitors the stress and strain of the lining through the lining piezoelectric monitoring module.

6. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 2, 4, or 5, characterized in that: The distributed piezoelectric geocable includes a piezoelectric geocable, multi-core conductors, and high-strength fiberglass fabric. The piezoelectric geocable includes a positive pole, a negative pole, and a PE sheath. The positive and negative poles are encapsulated within the PE sheath. Two of the multi-core conductors are welded to the positive and negative poles of the piezoelectric geocable, respectively. The piezoelectric geocable and multi-core conductors are sewn into the high-strength fiberglass fabric, and the inner and outer surfaces of the high-strength fiberglass fabric are coated with adhesive.

7. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 6, characterized in that: The piezoelectric monitoring network includes multiple distributed piezoelectric geoclines and a grid frame. The distributed piezoelectric geoclines are tied to the grid frame in a mesh-like pattern, and the distributed piezoelectric geoclines are electrically connected to the terminal monitoring equipment.

8. The tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 1 or 7, characterized in that: Multiple dampers are evenly distributed between the structural energy-absorbing layer and the piezoelectric monitoring network. The partition is fixed on top of the dampers, and the bottom of the composite energy-absorbing component is fixed on the partition.

9. The construction method of the tunnel life-cycle safety monitoring system based on impedance strain effect according to claim 1, characterized in that: step as follows: 1) Fabrication of distributed piezoelectric geocables, Two sensing wires from the multi-core conductor are welded to the positive and negative terminals of the piezoelectric geocable cable, then inserted into a high-strength fiberglass fabric with sewn stitches, and finally adhesive is added at the installation point; 2) Anchor bolt piezoelectric monitoring module, Before anchor bolt construction, the distributed piezoelectric geocable is fixed to the anchor bolt in the longitudinal direction using a steel bar-cable fastener, so that the anchor bolt and the high-strength glass fiber fabric are basically in contact. The initial strain state of the piezoelectric geocable is obtained using a data processing module, the arrangement is completed, and the next step of anchor bolt construction is carried out. 3) Lining piezoelectric monitoring module, Before binding the steel cages of the lining and secondary lining, the piezoelectric geocable of the lining is fixed to the longitudinal reinforcement of the lining steel cage using a steel bar-cable fastener, so that the longitudinal reinforcement of the lining steel cage is basically in contact with the high-strength glass fiber fabric. Then, the steel cage is bound to the stirrups of the lining steel cage. After completion, the initial strain state of the piezoelectric geocable of the lining is obtained using a data processing module, the arrangement is completed, and the next step of lining construction is carried out. 4) Ring piezoelectric monitoring module, At the location where the ring piezoelectric geocline needs to be installed, clean the lining surface. Along the tunnel cross-section, from the middle of the tunnel outwards every meter, drive expansion anchors into the tunnel wall. At the same time, install clamps on the anchors, insert the ring piezoelectric geocline, and tighten the screws to complete the arrangement of the piezoelectric geocline at the ring position. After completion, use the data processing module to obtain the initial strain state of the piezoelectric geocline to complete the arrangement. 5) Longitudinal Z-shaped piezoelectric axial force monitoring module, The system includes multiple distributed piezoelectric geoclines. During installation of each distributed piezoelectric geocline, the installation height is first determined. Then, two rows of expansion anchors are driven into the tunnel wall along the longitudinal direction of the tunnel. The first row of expansion anchors is driven in at equal intervals, and the second row of expansion bolts is distributed at equal intervals, located below the gap between the two expansion anchors in the previous row. Each expansion bolt is fitted with a clamp, and the distributed piezoelectric geoclines are sequentially fixed to the first and second expansion anchors with screws at intervals, forming a Z-shaped distribution. This process is repeated until all distributed piezoelectric geoclines are installed in a Z-shape on the tunnel wall. After completion, a data processing module is used to obtain the initial strain state of the Z-shaped longitudinal piezoelectric axial force monitoring geoclines, thus completing the layout. 6) Longitudinal piezoelectric temperature monitoring module, First, determine the installation height on the inner wall of the tunnel. Drive expansion anchors at regular intervals along the longitudinal direction of the inner wall of the tunnel. At the same time, install the clamps on the expansion anchors in sequence, then insert the distributed piezoelectric geocable cable, tighten the screws to complete the installation. Finally, use the data processing module to obtain the initial strain state of the longitudinal piezoelectric temperature monitoring module to complete the layout.

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