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CN-122016537-A - Anchoring bedding slope accelerated corrosion physical model test device and method

CN122016537ACN 122016537 ACN122016537 ACN 122016537ACN-122016537-A

Abstract

The utility model provides an anchor is along layer slope accelerated corrosion physical model test device and method, including casing, emulation rock mass, electrolyte system, mechanics loading system and observation system, be provided with a plurality of stock on the front side of emulation rock mass, through emulation rock mass simulation side slope structure, emulation rock mass and stock on it constitute emulation anchor system jointly, electrolyte system is used for making electrolyte circulate flow in emulation rock mass inside or around, mechanics loading system sets up in emulation rock mass's top, be used for exerting the pressure of vertical direction to emulation rock mass, thereby to the integration, synchronization simulation of lamellar slope geological structure, electrochemistry accelerated corrosion environment and multimode mechanics load. The design can simulate key elements in slope engineering, effectively improve fidelity of corrosion mechanism, simulate corrosion rate and accelerated degradation mechanism of stress concentration area of anchor rod, and effectively reveal dynamic coupling process.

Inventors

  • WANG DINGJIAN
  • HU XUETAO
  • CHENG JIANGTAO
  • ZHANG JICHENG
  • CHENG ZHIYUAN
  • FAN ZHIQIANG
  • WANG QIANYUN
  • Ouyang fang
  • XU LIANGJIE
  • NIE QIONG

Assignees

  • 湖北第二师范学院

Dates

Publication Date
20260512
Application Date
20260114

Claims (10)

  1. 1. An anchoring bedding slope accelerated corrosion physical model test device is characterized in that, The test device comprises a shell (1), a simulated rock mass (2), an electrolyte system (3), a mechanical loading system (4) and an observation system (5); The shell (1) is of a square box structure, and the simulated rock mass (2) and the mechanical loading system (4) are arranged in the shell (1); the simulation rock mass (2) is used for simulating a side slope structure, the simulation rock mass (2) is arranged on a fixed base (11) at the bottom of the shell (1), and a plurality of anchor rods (6) are arranged on the front side (21) of the simulation rock mass (2); The electrolyte system (3) is used for enabling electrolyte to circulate in or around the simulated rock mass (2); the mechanical loading system (4) is arranged at the top of the simulated rock body (2), and the mechanical loading system (4) is used for applying pressure in the vertical direction to the simulated rock body (2); the observation system (5) is used for monitoring the simulated rock mass (2) and each anchor rod (6) in real time and collecting experimental data.
  2. 2. The anchoring bedding slope accelerated corrosion physical model test device according to claim 1, wherein, The observation system (5) comprises a non-contact optical measurement device (51), an anchor rod mechanical monitoring device (52), a rock mass internal damage monitoring device (53) and a deep displacement measuring instrument (54); The non-contact optical measuring device (51) is at least two high-definition cameras with different shooting angles and is used for manufacturing a speckle field on the surface of the simulated rock mass (2) to obtain a full-field displacement vector and a strain tensor cloud picture of the surface of the simulated rock mass (2) in the loading and corrosion processes; The anchor rod mechanics monitoring device (52) comprises a plurality of anchor rod dynamometers and a plurality of resistance strain gauges, each anchor rod dynamometer is respectively arranged between an anchor head and a gasket of one anchor rod (6), the resistance strain gauges are arranged on the surfaces of the anchor rods, the anchor rod dynamometers are used for monitoring and recording axial force change histories of the anchor rods in real time, and the resistance strain gauges are used for measuring the strain of local areas of the anchor rods; The rock mass internal damage monitoring device (53) comprises a plurality of acoustic emission sensors, wherein the acoustic emission sensors are respectively arranged on the surface and the inside of the simulated rock mass (2) and are used for collecting acoustic emission signals generated by the rock mass in the stress and corrosion processes so as to monitor the development process of internal microcracks; The deep displacement measuring instrument (54) is a high-precision servo accelerometer inclinometer and is used for periodically measuring horizontal displacements at different depths of the anchor holes.
  3. 3. The anchoring bedding slope accelerated corrosion physical model test device according to claim 1, wherein, The simulated rock body (2) comprises a plurality of layers of rock plates (22) which are arranged in parallel and stacked, wherein the rock plates (22) are prepared by mixing Portland cement, calcareous sand and deionized water according to a preset mass ratio so as to simulate the physical and mechanical properties of a target rock stratum; Each layer of the rock plates (22) is subjected to interlayer interface roughening treatment or is paved with an extremely thin layer of weak material; rock stratum inclination angles exist between each layer of rock plates (22) and the fixed base (11); The front side (21) of the simulation rock mass (2) simulates a side slope structure through an inclined plane; the anchor rods (6) are inserted into anchor holes in the simulated rock mass (2) at the same angle; the anchor rods (6) are arranged on the simulated rock mass (2) in a matrix type, plum blossom type or engineering equivalent mode; The mechanical loading system (4) comprises a jack (41) and a bearing plate (42), a cylinder seat of the jack (41) is in contact with a top plate of the shell (1), the end part of a telescopic rod of the jack (41) is in transmission fit with the bearing plate (42), and the bearing plate (42) is arranged at the top of the simulated rock body (2).
  4. 4. The anchoring bedding slope accelerated corrosion physical model test device according to claim 1, wherein, A liquid inlet (12) is formed in the side wall of the front end of the shell (1), and a liquid outlet (13) is formed in the side wall of the rear end of the shell (1); The electrolyte system (3) comprises a circulating pump (31), a working electrode (32), an auxiliary electrode (33), a reference electrode (34) and an electrochemical workstation (35), wherein the circulating pump (31) is used for conveying electrolyte, the liquid outlet end of the circulating pump (31) is connected with the liquid inlet (12), and the liquid inlet end of the circulating pump (31) is connected with the liquid outlet (13); the working electrode (32) is connected with each anchor rod (6) in parallel, the auxiliary electrode (33) is arranged in electrolyte close to the front side (21) of the simulated rock body (2), and the reference electrode (34) is arranged in electrolyte close to the rear side of the simulated rock body (2); The signal input end of the electrochemical workstation (35) is respectively connected with the working electrode (32), the auxiliary electrode (33) and the reference electrode (34) in a signal manner; The electrochemical workstation (35) is used for applying a constant anode potential to the working electrode (32), monitoring the potential of the working electrode (32) relative to the reference electrode (34) in real time, and carrying out the potentiodynamic scanning or electrochemical impedance spectroscopy test on the total corrosion current flowing through the loops of the working electrode (32) and the auxiliary electrode (33) at the same time.
  5. 5. A test method for an accelerated corrosion physical model of an anchor bedding side slope according to any one of the claims 1 to 4, characterized in that, The test method comprises the following steps: s1, manufacturing a simulated rock body (2) according to a structure of a slope to be tested, drilling an anchor hole in the manufactured simulated rock body (2), installing a pretreated anchor rod (6) into the anchor hole, and arranging the simulated rock body (2) with the anchor rod (6) installed in a shell (1); S2, communicating the electrolyte system (3) with a liquid inlet (12) and a liquid outlet (13) on the shell (1), and installing the mechanical loading system (4) and the observation system (5) inside and outside the shell (1); s3, calibrating and initializing an electrolyte system (3) and an observation system (5); s4, carrying out corrosion experiments on the anchor rod (6) in stages under different experimental conditions by adopting a constant potential electrochemical acceleration method, and collecting experimental data in real time; s5, repeating the operation steps from S1 to S4 for three times, and respectively analyzing experimental data acquired in three times to obtain three sets of key parameter sequences; and S6, respectively carrying out multi-source information coupling on the three sets of key parameter sequences to obtain a failure early warning result.
  6. 6. The method for testing the physical model for accelerating corrosion of the anchor bedding slope according to claim 5, wherein the method comprises the steps of, In the step S4, the stage comprises a corrosion action period, a corrosion-load coupling period and an accelerated failure period; The duration of the corrosion action period and the corrosion-load coupling period is 240 hours; The experimental condition of the corrosion action period is that an electrolyte system (3) is started, at the moment, a circulating pump (31) starts to work, electrolyte circulation is formed in a shell (1), and meanwhile, a working electrode (32) applies constant potential of +8.0V to each anchor rod (6); The total corrosion current was recorded every 10 minutes during the corrosion period By total corrosion current Calculating the corrosion current density of each anchor rod (6) , Is the total number of the anchor rods (6), Is the number of any anchor rod (6), The method comprises the steps of obtaining by electrochemical impedance spectrum fitting, collecting stress data of all anchors (6) every (6) hours, and carrying out DIC full-field measurement every 24 hours to obtain DIC data; entering a corrosion-load coupling period after the corrosion action period lasts for 240 hours; The experimental condition of the corrosion-load coupling period is that a mechanical loading system (4) is started, at the moment, a jack (41) works in a graded loading-holding mode, the initial load of the graded loading-holding mode is 50kN, the load of each grade is increased by 50kN, and the load of each grade is maintained for 48 hours; Meanwhile, the working state of the electrolyte system (3) is unchanged; in the corrosion action period, the sampling frequency of all sensors is increased to 1Hz, and a rock internal damage monitoring device (53) continuously monitors in real time; Entering an acceleration failure period after the corrosion-load coupling period lasts for 240 hours; the experimental condition of the acceleration failure period is that the mechanical loading system (4) is switched to displacement control, the displacement of the slope top is continuously increased at the speed of (2) mm/min, and meanwhile, the working state of the electrolyte system (3) is unchanged; The test is terminated when any of the following conditions is satisfied: a. the stress of any anchor rod (6) is reduced to be below 30% of the initial value; b. The surface of the simulated rock mass (2) is provided with a through crack, and the width is more than 5mm; c. The deep displacement gauge (54) displays a sliding surface displacement rate of >1mm/min.
  7. 7. The method for testing the physical model for accelerating corrosion of the anchor bedding slope according to claim 5, wherein the method comprises the steps of, S5, preprocessing the acquired experimental data; The average etch depth is calculated based on Faraday's law: ; In the above-mentioned method, the step of, The total exposure area of 16 anchor rods is 16, M is the molar mass of iron, 55.85g/mol, F is Faraday constant, 96485C/mol, ρ is the density of iron, 7.87g/cm3, The total corrosion current density at the time T is the total corrosion time; Defining a corrosion non-uniformity coefficient: ; In the above-mentioned method, the step of, The corrosion current density of the ith anchor rod (6) at the t moment, The average corrosion current density at the time t is obtained by dividing the total corrosion current density at the time t by the total number of anchor rods (6); Drawing a corrosion current density space distribution cloud picture based on Kriging interpolation, and identifying a corrosion hot spot area; extracting key point displacement time course of shoulder and toe from DIC data; performing numerical differentiation on the inclinometry data to obtain curvature change of the displacement-depth curve; calculation of time t by DIC Strain field Shear strain of point ; Defining damage variables: ; In the above-mentioned method, the step of, =0.1%, Is the damage threshold, =2%, Is a destruction threshold; drawing a damage cloud picture, and counting the change of the damage area ratio along with time; Calculating the load sharing ratio of the ith anchor rod: ; In the above-mentioned method, the step of, The tension of the ith anchor rod (6) at the moment t; constructing a load distribution entropy value: ; In the above-mentioned method, the step of, The load sharing ratio of the ith anchor rod is the load sharing ratio; defining an effective constraint coefficient of the anchor rod: ; In the above-mentioned method, the step of, Is obtained by extracting DIC data for the displacement of local rock mass around the anchor rod, Is the pulling force of the ith anchor rod at the initial moment, Accumulating displacement of local rock mass of surrounding rock after deformation and damage of the side slope; Based on a limit balance method, a safety coefficient model considering corrosion weakening is established: ; In the above-mentioned method, the step of, As a safety factor, the safety factor of the device, 、 To take into account the rock mass strength parameters after erosion, For the bottom area of the ith bar, Is the inclination angle of the anchor rod, The sliding surface inclination angle is obtained by measuring the sliding surface inclination angle after the simulated rock mass (2) slides, For the weight of the bar The weight of the sliding part is obtained after the sliding of the simulated rock mass (2); acquiring acoustic emission accumulated energy sigma E through a rock mass internal damage monitoring device (53), and acquiring deep displacement velocity through a deep displacement measuring instrument (54) The displacement of the shoulder is obtained by a non-contact optical measuring device (51) ; Accumulating the acoustic emission accumulated energy sigma E and the deep displacement rate in three experiments Displacement of shoulder And total corrosion current Coefficient of corrosion non-uniformity Average corrosion depth Entropy of load distribution Safety factor And respectively packaging to form three key parameter sequences.
  8. 8. The method for testing the physical model for accelerating corrosion of the anchor bedding slope according to claim 5, wherein the method comprises the steps of, The steps of the multi-source information coupling are as follows: Aiming at each key parameter sequence, forming parameter pairs by two different key parameters in the key parameter sequence, and respectively calculating the interrelationship of each parameter pair through a sliding window cross-correlation function to obtain a correlation coefficient; Taking a parameter pair corresponding to the association coefficient larger than a set threshold as a causal parameter pair, and packing the causal parameter pair to obtain a causal relation set; And respectively identifying repeatable causal parameter pairs in the three causal relation sets, performing causal analysis on the causal parameter pairs, taking the cause parameters in the causal parameter pairs as precursor features, calculating an early warning index through the precursor features, and comparing the calculated early warning index with an early warning threshold value to obtain an early warning grade.
  9. 9. The method for testing the physical model for accelerating corrosion of the anchor bedding slope according to claim 8, wherein the method comprises the steps of, In the step S6, a sliding window cross-correlation function is calculated through a key parameter sequence, the width of the sliding window is 48 hours, the step length is 1 hour, and the method comprises the following steps: ; In the above-mentioned method, the step of, And X and Y are two key parameters in the parameter pair for the correlation coefficient.
  10. 10. The method for testing the physical model for accelerating corrosion of the anchor bedding slope according to claim 8, wherein the method comprises the steps of, In the step S6, the early warning index includes: ; In the above-mentioned method, the step of, Is the first The precursor is characterized in that Normalized data of the time of day, As a total number of precursor features, Is the first Weights corresponding to the precursor features; When the time is less than or equal to 0.3 When the temperature is less than 0.5, the I-level early warning is performed, and no signal is sent; when the time is less than or equal to 0.5% When the temperature is less than 0.7, a warning signal is sent for II-level warning; When (when) And when the temperature is more than or equal to 0.7, giving an alarm signal for III-level early warning.

Description

Anchoring bedding slope accelerated corrosion physical model test device and method Technical Field The invention relates to a corrosion test device, in particular to an anchoring bedding slope accelerated corrosion physical model test device and method. Background The layered rock slope is widely distributed in infrastructure construction areas such as mines, water conservancy and traffic, the stability of the layered rock slope is often dependent on reinforcing structures such as anchor rods (cables), however, in the long-term service process, the slope anchoring system not only bears the mechanical effects such as slope body dead weight, slope top load, structural stress and the like, but also continuously suffers from complex environmental corrosion such as chemical corrosion, electrochemical corrosion, corrosion and the like caused by groundwater seepage, and particularly in sulfur-containing stratum, acid mining areas or offshore environments, the corrosion problem is particularly prominent, the effective sectional area of the anchor rods is often reduced, the mechanical property is degraded, the bonding strength of an anchoring interface is lost, further progressive failure of the anchoring system is caused, even the whole slope is unstable, and engineering safety and service life are seriously threatened. At present, for the research of the performance of an anchoring side slope in a corrosion environment, a soaking method or a salt spray method is mostly adopted to carry out uniform corrosion test of a single medium on an anchor rod test piece, wherein the soaking method is to completely immerse the anchor rod test piece in a configured corrosion solution (such as NaCl solution, sulfate solution and the like), long-term corrosion is simulated by controlling the concentration, pH value and temperature of the solution, and the salt spray method is to expose the anchor rod test piece in a salt spray environment which is continuously or circularly sprayed in a salt spray test box, so as to simulate chlorine ion corrosion in the ocean atmosphere or an industrial pollution area. Although both corrosion test methods can simulate corrosion of the bolt in a specific environment, they still have the following drawbacks: 1. The local corrosion aggravating effect caused by the non-uniform seepage of groundwater along rock stratum cracks or pore networks in the actual side slope cannot be simulated, so that the coupling effect of electrochemical corrosion and chemical corrosion existing in a specific geological environment is difficult to reproduce, and the corrosion mechanism is distorted. 2. The corrosion rate of the stress concentration area of the anchor rod is obviously accelerated under the stress state, meanwhile, the section loss and interface weakening caused by corrosion can change the stress state, and an accelerated degradation mechanism of positive feedback is formed. The disclosure of this background section is only intended to increase the understanding of the general background of the application and should not be taken as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art. Disclosure of Invention The invention aims to overcome the defects that the corrosion mechanism is distorted and the dynamic coupling process cannot be revealed in the prior art, and provides a device and a method for testing an anchoring bedding slope accelerated corrosion physical model, wherein the corrosion mechanism is vivid and the dynamic coupling process can be revealed. In order to achieve the above object, the technical solution of the present invention is: an anchoring bedding slope accelerated corrosion physical model test device comprises a shell, a simulated rock mass, an electrolyte system, a mechanical loading system and an observation system; the shell is of a square box structure, and the simulated rock mass and the mechanical loading system are arranged in the shell; The simulation rock mass is used for simulating a side slope structure, and is arranged on a fixed base at the bottom of the shell, and a plurality of anchor rods are arranged on the front side of the simulation rock mass; the electrolyte system is used for enabling electrolyte to circularly flow in or around the simulated rock mass; the mechanical loading system is arranged at the top of the simulated rock body and is used for applying pressure in the vertical direction to the simulated rock body; The observation system is used for monitoring the simulated rock mass and each anchor rod in real time and collecting experimental data. The observation system comprises a non-contact optical measurement device, an anchor rod mechanical monitoring device, a rock mass internal damage monitoring device and a deep displacement measuring instrument; The non-contact optical measuring device is at least two high-definition cameras with different shooting angles and