49 results about "Stress redistribution" patented technology

The invention relates to the technical field of bridge engineering structure health monitoring, in particular to a service life prediction method and system for a bridge connection part, and the method comprises the steps: collecting the strain of a grouting sleeve, a reinforcement-grouting interface ultrasonic reflection signal and environment temperature and humidity data through a distributed sensor array; a three-dimensional dynamic void rate model is generated through fusion of a spatial topological mapping algorithm, a correlation function of load circulation and void expansion is established, the dynamic void rate is input into a bond strength coupling degradation model, after strength attenuation is quantized in combination with steel bar corrosion data and bond failure early warning is triggered, stress redistribution is calculated through multi-physics coupling simulation, and the dynamic void rate is obtained. Early warning is taken as a starting node, the actual load spectrum and temperature and humidity data are combined, Monte Carlo sampling is adopted to simulate rigidity degradation and output the residual life probability, the system comprises a multi-source collaborative sensing unit, a micro-void evolution analysis unit and a life prediction decision unit, and the safety control precision of bridge connection parts is improved.

The invention provides a tunnel surrounding rock deformation rolling time sequence prediction method and system considering excavation disturbance, and the method comprises the steps: obtaining a geometrical relationship from a tunnel face to a monitoring point, an excavation area and an excavation footage in a tunnel excavation process, and calculating a construction disturbance factor according to the obtained data; constructing and training a surrounding rock deformation prediction model, wherein the surrounding rock deformation prediction model is obtained by fusing a convolutional neural network, a bidirectional long-short term memory neural network and an attention mechanism layer; acquiring tunnel surrounding rock monitoring data, and preprocessing the monitoring data; and taking the preprocessed monitoring data and the calculated construction disturbance factor as input data of the trained surrounding rock deformation prediction model to obtain a final deformation prediction result. According to the method, the dynamic disturbance characteristics of stress redistribution in the tunnel excavation process are quantified into the construction disturbance factors, the nonlinear coupling relation between surrounding rock deformation and construction disturbance is analyzed through the hybrid model, and the tunnel surrounding rock deformation prediction accuracy is improved.

The invention belongs to the technical field of geotechnical engineering disaster prevention and reduction and earthquake engineering tests, and relates to a vibration table test method considering time-varying deterioration of anti-seismic performance of an anchored rock slope. The method comprises the following steps: firstly, constructing a dynamic performance time-varying deterioration model based on an anchoring system interface bonding force and a free section steel bar yield resistance attenuation rule; physical equivalent simulation of interface degradation and component yield resistance reduction is realized by regulating and controlling the proportion of rock mass similar materials and utilizing a graded rigidity anchoring system. The core of the method is that before a vibration table applies seismic waves, attenuation of the anchoring performance of a supporting structure is actively simulated in advance, so that a real evolution path that the bearing capacity of an anchoring system is reduced firstly, slope stress redistribution and accumulated damage are caused, and then sudden seismic loads are suffered is reproduced; the limitation that only the static low bearing capacity is simply simulated in a traditional test is broken through. According to the method, space-time coupling of static time-varying degradation accumulation and transient earthquake dynamic action is effectively achieved, the problems of interface degradation simulation distortion and the like are solved, and a reliable test method is provided for dynamic stability evaluation and reinforcement design of a long-term service anchoring slope.

The invention discloses a gradient combination anti-crack diaphragm wall concrete self-constraint stress optimization design method. The method comprises the following steps: firstly, constructing a BIM three-dimensional structure model comprising material performance, temperature gradient and stress state through three-dimensional laser scanning and core sample detection; then, carrying out stress partitioning based on the model, and calculating a self-constraint stress value and a stress transfer attenuation coefficient of each partition; then establishing an expanding agent proportion optimization model, simulating stress redistribution under different doping amount gradients by adopting a finite element algorithm, and screening a minimum effective doping amount meeting a stress homogenization index; and after the anti-cracking effect is verified through dynamic simulation, a final matching scheme is output. According to the method, the BIM technology and the material gradient design are combined, precise control over the concrete self-constraint stress of the underground diaphragm wall and active optimization of the crack resistance are achieved, the technical problem that traditional homogeneous material design is difficult to adapt to complex stress distribution is solved, and the durability and safety of the underground diaphragm wall structure are remarkably improved.

The invention discloses a reinforcing device and method for a side slope containing a weak intercalated layer, and belongs to the technical field of geotechnical engineering side slope reinforcement. The reinforcing device comprises a retaining wall and anchor cables, supplementary plates are arranged between units and are elastically connected, a water storage assembly is arranged on the side, close to the retaining wall, of the side slope, a water tank is arranged at the top of the retaining wall, and a water absorption assembly extending into the side slope is arranged on the retaining wall. The pushing assembly comprises a connecting cylinder, a connecting ring, an outer ring, a flexible pad and a corrugated pipe; the pump body at the water tank is connected with a hidden drainage header pipe and a water suction pipe through a three-way pipe; the retaining wall units, the pre-stressed anchor cables and the deep drainage system which are modularized are integrated, so that the cooperation of retaining, anchoring and drainage is achieved, and the defect that traditional measures are poor in collaboration is overcome. The water suction assembly is arranged, the pump body actively sucks water, the pore water pressure is efficiently reduced, and the problem that traditional gravity drainage is passive and low in efficiency is solved. The spring supplement plates between the retaining wall units can elastically adapt to uneven deformation of the side slope, stress redistribution is achieved, and the displacement can be monitored and pre-warned.

The application provides a method for determining the hole spacing of chamber blasting caving considering the effect of ground stress unloading, measures and records the original ground stress and rock mechanics parameters of the underground chamber blasting excavation engineering; establishes a stress analysis model with a slotting cavity according to the measured ground stress and caving blasting pre-design; carries out ground stress unloading calculation on the stress analysis model and establishes a ground stress redistribution model; constructs an explosion stress wave propagation model according to the rock material parameters and explosive material parameters and calculates the explosion stress superposition field between adjacent caving holes; calculates the maximum hole spacing of adjacent holes of caving blasting producing through cracks according to the rock strength fracture criterion. Through the calculation and analysis of the maximum effective distance of hole cracking under the coupling effect of ground stress redistribution and explosion load, the hole spacing design is avoided to be too small to cause large surrounding rock damage, the hole spacing design is avoided to be too large to be insufficient to form through cracks between holes, and the expected blasting excavation effect cannot be achieved.

The invention relates to the technical field of underground engineering support, and discloses an anchor rod active prestress releasing system for deep surrounding rock stability control, which comprises an anchor rod body, a prestress applying assembly, a surrounding rock state monitoring assembly, a prestress executing and releasing assembly and a central control unit. One end of the anchor rod body is anchored to the bottom of a deep surrounding rock preset drill hole, and the other end of the anchor rod body extends out of the drill hole. The prestress applying assembly is arranged at the end, extending out of the drill hole, of the anchor rod body in a sleeving mode and used for applying initial prestress to the anchor rod body. Surrounding rock stress and displacement data are collected in real time through the surrounding rock state monitoring assembly, the central control unit automatically judges and drives the prestress executing and releasing assembly to act according to a preset threshold value, and the limitation that a traditional anchor rod cannot be adjusted according to dynamic changes of surrounding rock after prestress is applied is broken through. And stress redistribution generated by excavation disturbance of the deep surrounding rock can be adapted in time.

The application discloses a load-bearing wall structure optimization design method based on parameterized modeling and belongs to the technical field of building structure design optimization. The method comprises the following steps: obtaining geometric boundary parameters, material attribute parameters and connecting node parameters of a load-bearing wall, and generating an initial wall parameter set; constructing a multiscale initial grid model comprising macroscopic scale grids and microscopic scale grids; applying a load boundary condition to perform nonlinear iterative solving to obtain a wall stress redistribution trajectory; identifying a high stress gradient area according to the stress redistribution trajectory, performing reverse correction on the initial wall parameter set by using regional local parameters and iteratively converging to generate an optimized wall parameter set. The method can accurately simulate local stress concentration at the connecting node, realize adaptive parameter optimization based on a stress transmission path, and improve design efficiency and structural economy.

The invention relates to the technical field of computer-aided engineering modeling, in particular to a prediction method and system for floor external corner cracks, and the method comprises the steps: collecting real-time temperature change data, concrete shrinkage deformation data, humidity information and sunlight intensity information of a floor external corner area; according to the method, a dynamic coupling model of temperature stress and concrete shrinkage is constructed, the influence coefficient of the temperature on the shrinkage rate and stress redistribution are calculated in real time in combination with a mechanical association algorithm, and the problem that dynamic interaction is not reflected due to independent calculation of the temperature stress and the concrete shrinkage in an existing method is solved; and then environment self-adaptive correction is performed on the model according to the humidity and the sunlight intensity, the sensitivity parameter and the temperature stress transmission attenuation coefficient are adjusted, and the defect that the real-time influence of environment factors is not included in an existing method is overcome.

The invention provides a method for determining the detonation speed of an explosive used for tunnel caving blasting by considering the influence of ground stress, and belongs to the technical field of blasting engineering and rock mass mechanics. Comprising the steps of obtaining rock mass mechanical parameters, blasting parameters and crustal stress data; establishing a stress analysis model based on ground stress and a blasting design drawing; establishing a crustal stress redistribution model caused by a cut cavity in the model, calculating radial pressure stress generated by crustal stress redistribution among the caving holes, and drawing a polar coordinate graph; establishing a collapse inter-hole explosion stress superposition model, and calculating circumferential tensile stress generated by explosion at the central points of the two holes; and based on the dynamic tensile strength and stress state of the rock, establishing a strength criterion for forming the inter-hole through crack, and deducing and solving the minimum explosive detonation speed required by the criterion. The blasting joint forming quality is effectively improved, back break is controlled, surrounding rock damage is reduced, and the safety, economical efficiency and reliability of blasting engineering are improved.

The invention provides a manufacturing method of a large slotted welding impeller, belongs to the technical field of impeller machining, and aims to solve the problem of deformation caused by redistribution of internal stress of the slotted welding impeller in a heat treatment process. The manufacturing method of the large slotting welding impeller comprises the steps that S1, the impeller cover and the impeller disc are subjected to pre-welding machining; s2, the wheel cover and the wheel disc are welded together through the lap joint seam allowance, and an impeller is formed; s3, post-heat treatment and stress relief treatment are conducted on the impeller; s4, a lap joint spigot of the impeller cover and the impeller disc is removed, so that an outlet is formed in the circumferential direction of the impeller; s5, shot blasting treatment is conducted on the impeller; s6, the impeller is machined before heat treatment, and the impeller with the non-uniform allowance and the structure before heat treatment is formed; s7, the impeller is subjected to heat treatment; and S8, the impeller is subjected to finish machining so that the design size can be achieved. According to the method, the deformation risk of the impeller in the heat treatment process is effectively reduced, and the manufacturing precision and the quality stability of the large slotting welding impeller are improved.

The invention belongs to the technical field of material science foundation, and discloses a single twinborn system dominated twinborn transmission probability prediction method. According to the method, aiming at the condition that a single twin system is started preferentially under specific texture and force field conditions, the uniqueness of the twin system is limited and activated, and a three-dimensional matrix expression system of specific twin system spatial orientation is constructed. And based on a judgment rule that twin crystal faces and twin directions of the two crystal grains are parallel, calculating the minimum orientation difference capable of realizing parallel twin systems among the crystal grains. According to the method, the twinborn orientation difference is provided as a key physical quantity for quantifying the twinborn transmission capability, and the regulation and control mechanism of single twinborn system activation on local stress redistribution is disclosed by eliminating the interference of a non-activated twinborn system. The method is applicable to a twin-dominated deformation system at low temperature or high strain rate, and provides a micromechanical basis for optimizing strain coordination at the grain boundary.

This invention belongs to the field of tunnel and underground engineering structural safety testing technology, specifically relating to an indoor test bench and method for simulating rock mass unloading deformation and active-passive coordinated support in a tunnel model. The test bench includes a reaction bearing frame, multiple radial loading components arranged circumferentially along the reaction bearing frame, and a bottom support component. The radial loading components can independently set and maintain their loading displacement or equivalent load, and can perform zoned unloading / unloading and reloading according to a preset zone sequence to simulate the unloading deformation path and stress redistribution of the surrounding rock caused by tunnel excavation. This invention enables controllable indoor reproduction of the entire process of surrounding rock unloading path—active support sequence—passive lining failure, providing a test platform for support optimization.

The invention provides an inter-panel ore pillar bidirectional pressure relief mining method based on hanging wall and footwall surrounding rock roadways, and belongs to the technical field of mining engineering.The inter-panel ore pillar bidirectional pressure relief mining method comprises the steps that S1, a hanging wall pressure relief roadway and a footwall pressure relief roadway are tunneled in stable surrounding rock on one side of a hanging wall and one side of a footwall of an inter-panel ore pillar respectively, and the axes of the two pressure relief roadways are parallel to the walking direction of the inter-panel ore pillar; s2, the hanging wall pressure relief roadway and the footwall pressure relief roadway serve as safe operation spaces, and a rock drilling device drills pressure relief drill holes in the direction of the contact boundary of the ore pillar and the surrounding rock; stress sudden rise caused by stress redistribution of the other side due to single-side pressure relief is avoided in the step S1, the design that pressure relief drill holes are drilled in the step S2 till the pressure relief drill holes completely penetrate through the contact boundary of the ore pillar and the surrounding rock is combined, and therefore a mitigation fissure zone is formed in the contact boundary, stress in the inter-plate ore pillar is effectively released, and the stability of the inter-plate ore pillar is improved. The invention provides the method for releasing the internal stress of the ore pillar, which is low in cost and can maintain the original bearing capacity of the inter-plate ore pillar.

The invention relates to the technical field of coal mine safety mining, and discloses a lateral roof double-area pre-cut seam pressure relief method and system, and the method comprises the steps: measuring the range of a surrounding rock loosening circle to solve an initial pressure relief position; establishing a stress dynamic monitoring array in a section coal pillar, collecting data in real time and extracting a stress concentration peak value distance of a solid coal side; preferentially determining the vertical height of the pressure relief horizon according to the geological parameters and the overlying strata structure; calculating first-stage parameters such as a drilling deflection angle based on the variables, and preferentially performing seam cutting on the entity coal side of the adjacent working face; the stress redistribution state is tracked in the observation window period, the corrected peak value distance of the auxiliary transportation entry retaining side is obtained, and according to the corrected peak value distance, second-stage parameters are solved, and differential joint cutting is completed. According to the method, a dynamic closed-loop feedback mechanism is constructed through a double-region and step-by-step time sequence strategy, it is ensured that the joint cutting position is accurately matched with the mining-induced stress extreme value region all the time, high stress transmission is effectively blocked, and the problem of surrounding rock instability induced by lateral bearing pressure superposition is solved.

The invention relates to the technical field of land subsidence disaster early warning, in particular to a land subsidence micro-motion monitoring system and method. The system comprises a geomechanical model construction module, a micro-motion event interpretation module, a damage-stress coupling evolution module and a risk probability prediction module. The system obtains seismic moments by interpreting a micro-seismic event in real time; the core of the method is that a current accumulated damage factor, real-time shear stress and normal stress are solved by applying a damage amplification effect based on seismic moments and historical accumulated damage factors, and a time-varying instability risk index and an instability probability are predicted; according to the method, discrete micro-seismic data are assimilated into continuous damage accumulation and stress redistribution processes in the rock-soil body, and conversion from passive recording to internal state quantitative early warning is achieved.

This application belongs to the field of landslide prediction technology, and relates to a method for predicting landslides at tunnel entrances using shallow seismic-stress joint inversion. This invention acquires first-arrival wave travel time data of the slope using a high-frequency seismic source array, constructs a geological model including a rock mass integrity coefficient matrix, identifies rock mass structural deterioration through elastic wave velocity distribution, and identifies potential unstable structural weak areas in advance. Then, the rock mass integrity coefficient matrix is ​​embedded as prior knowledge into the stress field solution. By establishing the coupling relationship between seismic wave propagation and stress, the stress field distribution of the slope is inverted, capturing early stress redistribution signals caused by structural deterioration in deep rock masses, achieving early detection of precursors to mechanical instability. Furthermore, based on stress and strain data, the strain energy density distribution of the potential slip surface is calculated. By judging whether the strain energy density exceeds a threshold, whether it is continuous, and whether the expansion rate exceeds the standard, the potential slip surface can be accurately identified before it is fully connected, avoiding the lag caused by relying on displacement signals.

The present application relates to the field of ground subsidence disaster early warning technology, in particular to a ground subsidence micro-motion monitoring system and method thereof; comprising a geomechanical model construction, micro-motion event interpretation, damage-stress coupling evolution, risk probability prediction module; the system obtains seismic moment by real-time interpretation of microseismic events; the core is based on seismic moment and historical cumulative damage factor, applying damage amplification effect, calculating the current cumulative damage factor, real-time shear stress and normal stress, and predicting time-varying instability risk index and instability probability; the present application assimilates discrete microseismic data into continuous damage accumulation and stress redistribution process in rock-soil body, realizing the change from passive recording to internal state quantitative early warning.

The invention provides an expressway engineering construction real-time monitoring method and system based on big data, and the method comprises the steps: collecting the initial stress and deformation data of a supporting system in an installation completion state before concrete is poured, and constructing a stress monitoring reference; in the continuous concrete pouring process, real-time stress and deformation data of a supporting system are collected according to the construction stage, the increment of the real-time stress and deformation data relative to a stress monitoring benchmark is calculated, and a stress increment time sequence data set bound with the construction process is formed; analyzing the change trend and distribution relation of the internal force of the support system based on the stress increment time sequence data set, identifying the stress redistribution phenomenon, and evaluating the distance between the current state and the bearing limit to judge the critical state; according to the method, the construction mechanics principle and real-time data can be deeply fused, the internal stress evolution law of a supporting system is informed, and advanced early warning and decision guidance are achieved in the invisible risk stage.

The application discloses a kind of soft interlayer containing slope reinforcement device and method thereof, belong to geotechnical engineering slope reinforcement technical field, including retaining wall and anchor cable, unit is equipped with supplementary plate and is elastically connected, there is water storage component in the side of slope near retaining wall, water tank is arranged at the top of retaining wall, there is water suction component extending to the slope in retaining wall, push component contains connecting barrel, connecting ring, outer ring, flexible pad, bellows, pump body is connected with water suction pipe through three-way pipe in water tank place drainage underground main pipe;The application realizes supporting, anchoring and drainage cooperation by integrating modular multiple retaining wall units, prestressed anchor cable and deep drainage system, overcomes the poor synergy of traditional measures. The setting of water suction component, the active suction of pump body, efficient reduction of pore water pressure, solves the problem of passive inefficiency of traditional gravity drainage. Spring supplementary plate between retaining wall units can elastically adapt to uneven deformation of slope, realize stress redistribution, and its displacement can be monitored and early warned.

The application provides a calculation method of a crown arch surrounding rock collapse depth considering excavation unloading stress redistribution, comprising the following steps: step S1: a triangular formula is used to calculate the collapse arch height before excavation; step S2: a tunnel radius, surrounding rock bulk density, cohesive force and internal friction angle are collected; step S3: stress decomposition and stress redistribution analysis are carried out after excavation, and the crown arch surrounding rock collapse depth is obtained. The crown arch surrounding rock collapse cavity depth of the tunnel can be more accurately predicted, the surrounding rock support force is determined, and a reasonable dynamic design basis is provided for the tunnel construction through a fault fracture zone.

The present application belongs to the field of geotechnical engineering disaster prevention and mitigation and earthquake engineering test technology, and relates to a shaking table test method considering time-varying degradation of seismic performance of anchored rock slope. The method first constructs a dynamic performance time-varying degradation model based on the attenuation law of the interface bonding force of the anchoring system and the yield resistance of the free section reinforcement; by adjusting the proportion of the rock similar material and using a staged stiffness anchoring system, the physical equivalent simulation of interface degradation and component yield resistance reduction is realized respectively. The core of the present application is that before the shaking table applies the seismic wave, the anchoring performance degradation of the supporting structure is simulated actively in advance, so as to reproduce the real evolution path that the bearing capacity of the anchoring system decreases first, leading to stress redistribution and cumulative damage of the slope, and then suffering from sudden seismic load, breaking through the limitation of traditional test which only simply simulates static low bearing capacity. The present application effectively realizes the space-time coupling of "static time-varying degradation accumulation" and "instantaneous seismic dynamic action", solves the problem of simulation distortion of interface degradation, and provides a reliable test method for dynamic stability evaluation and reinforcement design of long-term service anchored slope.

This invention discloses a method for evaluating the creep life of high-temperature pipelines based on a physical information neural network. The method includes: obtaining the three-dimensional residual stress distribution of the welded joint region of the high-temperature pipeline based on welding thermo-mechanical coupled finite element simulation or residual stress measurement, and using this as the initial stress field for creep analysis; based on the initial stress field, constructing a stress redistribution model considering service temperature, internal pressure, structural constraints, and material creep effects to obtain the stress field distribution evolving over time; based on the evolved stress field, constructing a physical information neural network model incorporating creep constitutive relations and stress balance constraints to predict the creep strain or creep damage evolution process in key areas of the welded joint, and determining the creep life of the high-temperature pipeline by combining creep failure criteria. This invention can reasonably reflect the relaxation and redistribution behavior of welded residual stress during long-term high-temperature service, thereby improving the reliability of creep life evaluation of high-temperature pipeline welded joints.

The invention relates to the technical field of building node reinforcement, in particular to a multi-direction limiting and stress redistribution integrated restraint device for a bolt-sphere node, which comprises a first direction restraint part, a front restraint part, a restraint connecting part and a second direction restraint part, the two first direction constraint parts are symmetrically arranged on two force bearing structures in the first direction of the cross spherical hinge joint; the two constraint connecting parts are symmetrically arranged at the positions, close to the spherical hinge joint, of the two force bearing structures in the first direction of the cross-shaped spherical hinge joint. The binding connecting part is arranged between the first direction binding part and the front binding part, and the binding connecting part is used for limiting relative movement between the first direction binding part and the front binding part; the two second direction constraint parts are symmetrically arranged on the two force bearing structures in the second direction of the cross spherical hinge joint; the end parts of the first direction binding part and the second direction binding part are connected with each other to form a closed rectangular structure.

The invention discloses a rock breaking device and method with cooperation of ultrasonic drilling and shield cutting, and relates to the technical field of hard rock efficient breaking. The rock breaking device comprises a shield tunneling machine cutting system and an ultrasonic vibration drilling device. During construction, the size of a target cutting face of a hard rock to be constructed is determined firstly, and parameters of the large-diameter pressure relief empty hole are determined in combination with rock mechanical parameters; then the ultrasonic vibration drilling device is fixedly arranged at the circle center of a cutter head of the shield tunneling machine, a large-diameter pressure relief empty hole is drilled through the ultrasonic resonance effect, the cutter of the shield tunneling machine cuts the rock after pressure relief, the ultrasonic vibration drilling rate and the cutter head cutting rate are synchronously controlled, and parallel operation of ultrasonic vibration drilling and shield cutting is achieved. According to the method, the radius and the length of the empty hole are quantitatively designed according to the elastic-plastic mechanics principle, so that a pressure relief area covering the whole section of the shield is formed on the periphery of the empty hole, stress redistribution and strength degradation of hard rock are achieved, meanwhile, the adaptive relation between empty hole parameters and the rock breaking speed is determined, and optimization of the rock breaking efficiency is achieved.

This invention relates to a structural design method for ductile biomimetic reinforced concrete finite disintegration short columns. It employs short steel pipes to constrain the reinforcing bars at adjacent corners of four separate columns, forming a tight structural connection. This allows the four columns to have coordinated deformation capabilities, preventing crack development caused by pilot cracks from occurring outside the short steel pipes, thus achieving finite disintegration. The spine-like effect formed by the short steel pipes and the core concrete exhibits good toughness. The encased longitudinal reinforcing bars act as reinforcements and enhance the overall integrity between the short steel pipes, providing a certain degree of lateral deformation. The short steel pipes possess strong load-bearing capacity and do not suffer from the localized protrusion problem common in steel-concrete composite structures. The longitudinal cross-sectional stress of the concrete constrained by the short steel pipes is uniform, and the strength and deformation capacity of the core concrete constrained by the steel pipes are improved. The entire cross-section undergoes stress redistribution due to the structural method, resulting in a ductile development process. When its area exceeds one-third of the total cross-section, it can bear the entire ultimate load of the short column.

The invention discloses a pressure relief method for penetrating a surrounding rock stress peak region, which comprises the following steps: S1, acquiring geological parameters and an initial stress state of surrounding rock, and establishing a surrounding rock stress distribution model; s2, determining the position and range of a stress peak region based on a surrounding rock stress distribution model, and planning a pressure relief region and a stress transfer direction; s3, according to the position of the stress peak region and the planned stress release and transfer path, pressure relief drilling parameters are designed, and a pressure relief drilling arrangement scheme is formed; s4, pressure relief drill holes are constructed according to the pressure relief drill hole arrangement scheme, efficient release of stress in a peak value area is achieved, and the stress peak value area is promoted to be transferred to the deep part of the surrounding rock; and S5, setting observation points to monitor the pressure relief effect, and evaluating the stress redistribution state of the surrounding rock. A possible unstable coal damage process is changed into a stable damage process, and the method is an effective measure for reducing or eliminating the danger of deformation and damage of the surrounding rock of the roadway.

The invention discloses a CO2 storage multi-field coupling safety evaluation method considering fracture evolution, and relates to the technical field of complex oil and gas reservoir development, and the CO2 storage multi-field coupling safety evaluation method comprises the following steps: s1, constructing and solving a multi-field coupling model; s2, virtual crack grid construction and expansion: according to the updated model stress field parameters, judging whether cracks are generated or not, and if so, constructing and expanding a corresponding virtual crack grid; s3, evaluating the integrity of the cover layer: after each time step is finished, evaluating the integrity of the cover layer; and continuing numerical simulation of the next time step until the simulation is finished. According to the method, comprehensive coupling of multiple physical fields such as crack generation and expansion, CO2 seepage, heat transfer between the injected CO2 fluid and the reservoir and between the injected CO2 fluid and the reservoir fluid, geological stress redistribution and the like in the CO2 storage process is fully considered, so that the spatial and temporal change of each physical field in the reservoir in the CO2 injection process can be truly represented, the simulation precision is greatly improved, and the simulation efficiency is improved. And the uncertainty caused by fixed parameters or simplified processing is effectively reduced.

The invention relates to the technical field of constructional engineering structure testing, in particular to an underground space large-span full-scale prestressed plate ribbed beam pile-loading test method, and aims to solve the problems that an existing scale test is distorted due to the size effect, a counter-force system is not matched with the underground environment, monitoring of key parts is missing, and loading data is incomplete. The method comprises the following steps: constructing a full-scale prestressed plate rib beam test body and an underground adaptive counter-force system based on actual engineering geology and structure; sensors are arranged at key parts such as a middle plate span, a ribbed beam support and a prestressed tendon anchoring area; the hydraulic jacks are used for graded loading, and each stage is kept to be stable in deformation; synchronously acquiring strain, displacement and prestress data; and processing data, analyzing rigidity evolution, a prestress effect, stress redistribution and a failure mode, and evaluating the bearing capacity and the safety reserve of the structure. According to the method, actual working conditions of engineering are reproduced, data are accurate and comprehensive, and design optimization and safety application of the underground space prestressed plate ribbed beam can be directly guided.

The application provides a soft rock tunnel surrounding rock stress redistribution prediction method, and belongs to the technical field of soft rock tunnel construction. The original rock three-direction principal stress data are obtained by adopting the borehole stress relief method and the hydraulic fracturing method, the data are input into a mixed inversion system to construct a three-dimensional initial stress field distribution model before tunnel excavation, the surrounding rock deformation is controlled by implementing advanced pre-reinforcement and reserving core soil, a microseismic monitoring sensor array is laid to collect surrounding rock micro-fracture signals in real time, the initial stress field distribution model and the monitoring data are input into a fully coupled finite element solver, a fractional order creep constitutive model is established to describe the soft rock aging deformation characteristics, and a construction process digital twin system is constructed. The monitoring data is assimilated to the system by using an extended Kalman filtering algorithm to dynamically update the surrounding rock stress redistribution prediction results. According to the prediction results, the support parameters are adjusted, and the problem of low prediction accuracy of soft rock tunnel surrounding rock stress redistribution is solved.