54 results about "Shear displacement" patented technology

The invention belongs to the technical field of direct shear-seepage tests of rock joints, and discloses a numerical test method for direct shear-seepage of rock joints under different boundary conditions, which comprises the following steps of: establishing a joint surface numerical model by using finite element software, and performing tests for simulating joint shear mechanical behaviors by applying different boundary conditions. And the contact state and the opening distribution of the joint surface under different shear displacements are obtained, so that the shear stress evolution mechanism of the joint surface is better revealed, and the mechanical behavior of the rough joint surface in the shear process is accurately expressed. According to the method, the evolution law of mechanical properties in the joint shearing process can be reflected, the influence of shearing deformation on the joint seepage characteristics can be reflected, joint opening data distribution is imported into programming software to be processed, a joint seepage numerical model is constructed, then multi-physics field simulation analysis software is imported, and the joint seepage performance is improved. The flow velocity, the osmotic pressure and the streamline distribution characteristics in the flowing process are calculated, so that the joint permeability characteristics are analyzed.

The invention relates to the technical field of anchoring structure design, in particular to a method for determining the critical anchoring length of an anchor rod based on numerical simulation. Firstly, the critical anchoring length is determined, a short anchor rod pull-out test is conducted on site, a pull-out force and displacement curve of the anchor rod is obtained through the field test, the pull-out displacement curve is converted into the relation between shear stress and shear displacement through a formula, then numerical simulation is conducted, FLAC3D is selected for numerical simulation of the pull-out test, and the tensile strength of the anchor rod is improved. By increasing the nodes of the pile structure units and continuously increasing the drawing length of the anchor rod, a large number of tests do not need to be carried out on site, the influence of site environment and human factors on the determination of the anchoring length of the anchor rod does not need to be considered, manpower and material resources are saved, and the mechanical property of site surrounding rock is not destructed; and engineering can be well adapted.

The invention discloses a shear creep tester for in-situ slip zone soil and a test method, and relates to the technical field of rock-soil in-situ tests.The shear creep tester comprises a shear box, a shear load system, a normal load system and a ball row structure, and the shear box comprises an upper pressure box and a lower pressure box; the shear load system comprises a first spherical base, a shear stiffness self-adaptive loading assembly and a shear displacement sensor, and the shear displacement sensor is used for measuring the shear displacement of the shear box; the normal loading system comprises a second spherical base, a normal stiffness self-adaptive loading assembly and a normal displacement sensor, and the normal displacement sensor is used for measuring the normal compression amount of the soil body sample in the shear box; the ball row structure is suitable for reducing friction force between the normal rigidity self-adaptive loading assembly and the upper pressure box. The problems that the loading direction and the loading stability are controlled in an existing in-situ slip band soil shear creep test, and a slip band soil microstructure evolution detection device is lacked are solved.

An internal and external coupling shear resistance locking control system and monitoring method of tunnel surrounding rocks, comprises an internal shear resistance and monitoring system of tunnel surrounding rocks, an external shear resistance and monitoring system of tunnel surrounding rocks, a relative shear displacement monitoring system of the tunnel walls and the roof and floor layers, and an anchor agent installation system; holes are expanded in the anchor cable drilling holes passing through coal-rock interface areas of the coal walls and roof and floor rock layers to form shear misalignment tolerance cavities; monitoring pressure values of measuring bags and liquid discharge in the shear misalignment tolerance cavities to determine shear deformations of the shear misalignment tolerance cavities, monitoring forces on anchor cables, compensating pull rods and shear resistance steel strips, and adjusting the shear resistance of the anchor cable and steel belt through the compensation rod structure.

The invention discloses a model construction method considering the strain hardening and softening characteristics of a rib-soil interface, and the method comprises the steps: setting normal stress as a single variable, and obtaining a plurality of shear stress-shear displacement curves under different normal stress levels of a to-be-tested soil sample through a pull-out test; a model is established according to the influence rule of normal stress on the characteristics of the rib-soil interface and the change characteristics of the interface shear stress in the shearing process. According to the model considering the strain hardening and softening characteristics of the reinforcement-soil interface, the characteristics of the reinforcement-soil interface in different stress states can be predicted more accurately, the efficiency is high, and the cost is low.

The invention relates to the technical field of mechanical testing of materials, in particular to an automatic testing system and method for shear strength of a mine filling body, and the system comprises a critical state recognition module which collects real-time data of shear force and shear displacement of the mine filling body in the process of testing the shear strength of the mine filling body and converts the real-time data into a curve for representation; and calculating a gradient mutation point of the curve, and marking a key state change position in the shearing process by referring to the gradient mutation point to obtain parameter characteristics at the shear failure moment. According to the method, dynamic data of shearing force and shearing displacement are collected in real time and converted into a shearing curve, gradient mutation points in the curve are accurately calculated, key state changes of the shearing process are marked, the critical state of converting the shearing bearing capacity of the material into structural instability is recognized, and a key basis is provided for analysis of the shearing strength.

The invention discloses a slope dynamic safety coefficient calculation method based on large rock mass shear displacement. The slope dynamic safety coefficient calculation method comprises the following steps: establishing a relational expression between shear stress tau and a rock interface total area S; constructing a shear constitutive model of the small-size rock sample in combination with a classical structural surface shear stress-displacement curve and Weibull distribution; converting parameters in the shear constitutive model of the small-size rock sample into corresponding large rock mass parameters, and constructing a large rock mass shear constitutive model; and the real-time shear displacement of the slip mass is substituted into the large rock mass shear constitutive model, and the dynamic safety coefficient of the slope is obtained. According to the method, a new large rock mass shear constitutive model is constructed, and based on an expression of the large rock mass shear constitutive model, the shear displacement of the sliding mass is substituted into the large rock mass shear constitutive model, so that the shear displacement of the rock mass can be used for calculating the dynamic safety coefficient of the slope.

The invention relates to a concrete and rock mass bonding interface mechanical property in-situ test device and a test method. The method is suitable for the technical field of geotechnical engineering. According to the technical scheme, a concrete test block is poured on a rock mass; the test box is arranged around the concrete test block, and the test box is fixed on the rock mass; the shearing force loading mechanism is used for applying shearing force to the concrete test block in the front-back direction; the shear displacement acquisition mechanism is used for acquiring the shear displacement of the concrete test block; the normal force loading mechanism is used for applying normal force to the concrete test block through the pressing plate mechanism; the pressing plate mechanism comprises an upper pressing plate and a lower pressing plate, the upper pressing plate is connected with the normal force loading mechanism, the upper pressing plate can be movably pressed on the lower pressing plate along the front-back direction through a low-friction mechanism, and the lower pressing plate is adhered to the upper surface of the concrete test block; the normal displacement acquisition mechanism is used for acquiring the normal displacement of the concrete test block; and the data acquisition instrument is connected with the shear displacement acquisition mechanism and the normal displacement acquisition mechanism through data lines.

The invention discloses a loess-mudstone landslide sliding grading displacement measurement method and system, and the method comprises the following steps: collecting the multi-point displacement data of a landslide body, and carrying out the preprocessing of the data, and generating a standardized multi-measurement-point displacement data sequence; obtaining overall and local deformation states; extracting evolution trend, space consistency and sliding loss features to form a displacement feature set; inputting an improved continuous time hidden Markov landslide state model, and generating a sliding state evolution sequence; analyzing the evolution sequence to generate a grading judgment result; an included angle threshold method and a shear displacement gradient method are adopted to recognize a concave-convex body and a sliding belt, and a key area identification result is generated; and outputting a sliding grading judgment result, a displacement feature set and a key area identification result. According to the invention, fine grading identification of the landslide state and accurate locking of the key area are realized, and the accuracy and foresight of monitoring and early warning are improved.

The present invention relates to the technical field of material mechanics testing, specifically an automated testing system and method for the shear strength of mine backfill. The system includes: a critical state identification module that collects real-time data of the shear force and shear displacement of the mine backfill during the shear strength test of the mine backfill, converts it into a curve representation, calculates the gradient mutation points of the curve, and marks the key state change positions during the shear process with reference to the gradient mutation points to obtain the parameter characteristics at the moment of shear failure. In the present invention, by collecting the dynamic data of the shear force and shear displacement in real time and converting them into a shear curve, accurately calculating the gradient mutation points in the curve, marking the key state changes during the shear process, and identifying the critical state where the material changes from shear bearing capacity to structural instability, it provides a key basis for the analysis of the shear strength.

The application provides a method and device for predicting normal displacement of soft rock joint surface, electronic equipment and medium. The method comprises the following steps: firstly, determining residual shear dilation angle of the joint surface and displacement maximum value of the soft rock in the elastic stage; if the shear displacement is less than or equal to the displacement maximum value of the soft rock in the elastic stage, determining the first joint surface closure displacement according to the shear displacement and the shear closure coefficient, and obtaining the predicted joint surface normal displacement; if the shear displacement is greater than the displacement maximum value of the soft rock in the elastic stage, determining the opening displacement caused by the joint surface climbing effect according to the shear displacement, the normal stress, the residual shear dilation angle and the displacement maximum value of the soft rock in the elastic stage; determining the second joint surface closure displacement according to the opening displacement and the shear closure coefficient; and taking the sum of the opening displacement caused by the joint surface climbing effect and the second joint surface closure displacement as the predicted joint surface normal displacement. The application can predict the joint surface normal displacement according to the size of the shear displacement.

The present invention discloses a reinforcement-soil interface friction characteristic test device and test method, the device comprises a fiber-soil model box, a portable fiber fixing device, a test platform body, a water drop loading device, a traction pulley device, a horizontal observation device, a test platform leveling device, a vertical loading device, a laser displacement sensor and a computer. The present invention obtains the shear stress-strain relationship between the fiber and soil interface under different loads by adjusting the size of the overlying load, thereby obtaining the test parameters such as the shear strength, interface cohesion, internal friction angle, shear displacement, etc. of the interface, and can realize the study of the effect and mechanism of the influence of parameters such as different soil qualities and different fiber types on the test by changing the soil type, soil properties, fiber type, etc., especially for the test study of the friction characteristics of the reinforcement-soil interface of fiber-reinforced soil, revealing the laws of stress and deformation of the reinforcement-soil interface.

The present invention relates to a semi-analytical method for determining the fracture toughness and bridging stress of an end-load splitting mode of a composite material laminate, comprising the following steps: (1) designing and manufacturing a composite material specimen for an end-load splitting test; (2) carrying out a delamination test using a test device; (3) recording the test load and displacement to obtain the specimen flexibility; (4) measuring the initial delamination length of the specimen and the delamination length at unloading and the corresponding specimen flexibility to obtain expressions for the bending modulus and shear modulus; (5) deriving an expression for the fracture toughness; (6) deriving an expression for the shear displacement of the prefabricated crack tip; (7) fitting a relationship curve between the fracture toughness and the shear displacement of the prefabricated crack tip; (8) differentiating the relationship curve with respect to the shear displacement of the prefabricated crack tip to obtain the bridging stress; the semi-analytical method proposed in the present invention can be used to determine the fracture toughness and bridging stress in the end-load test of composite materials without the need to monitor the crack length in real time or design additional tests, thereby simplifying the test process, shortening the test cycle, and improving the accuracy of the measurement results.

The application discloses a kind of applied loess-mudstone landslide sliding grading displacement measurement method and system, including the following steps: collecting landslide body multi-point displacement data, pre-processing generates standardization multi-measurement point displacement data sequence;Obtain overall and local deformation state;Extract evolution trend, spatial consistency and sliding loss characteristics, form displacement feature set;Input improved continuous time hidden Markov landslide state model, generate sliding state evolution sequence;Analysis evolution sequence generates grading determination result;Adopt angle threshold method and shear displacement gradient method to identify concave-convex body and sliding zone, generate key area identification result;Output sliding grading determination result, displacement feature set and key area identification result.The application realizes landslide state fine grading identification and key area accurate locking, improves the accuracy and foresight of monitoring and early warning.

The present invention discloses a dynamic seepage device and method under impact load, the device comprises a loading device, a device body, and a water supply system, wherein the loading device is arranged in the device body, and the water supply system is connected to the device body. The present invention aims at solving the technical requirements of how to solve the current problem of sand liquefaction, which is completed under vibration load or large shear displacement conditions, and most of the studies maintain an undrained state, and rarely consider the liquefaction response of the bottom of saturated sand after being impacted. A dynamic seepage device and method under impact load are proposed, which can better observe the sand sample changes and liquefaction response of the sand when the bottom is impacted, and analyze the changes in the speed of seepage under dynamic load by recording data through sensors. The present invention can observe the sand sample changes and its liquefaction response when the bottom is impacted, and can also observe the changes in the speed of seepage under different dynamic loads.

An internal and external coupling shear resistance locking control system and monitoring method of tunnel surrounding rocks, comprises an internal shear resistance and monitoring system of tunnel surrounding rocks, an external shear resistance and monitoring system of tunnel surrounding rocks, a relative shear displacement monitoring system of the tunnel walls and the roof and floor layers, and an anchor agent installation system; holes are expanded in the anchor cable drilling holes passing through coal-rock interface areas of the coal walls and roof and floor rock layers to form shear misalignment tolerance cavities; monitoring pressure values of measuring bags and liquid discharge in the shear misalignment tolerance cavities to determine shear deformations of the shear misalignment tolerance cavities, monitoring forces on anchor cables, compensating pull rods and shear resistance steel strips, and adjusting the shear resistance of the anchor cable and steel belt through the compensation rod structure.

The invention relates to the technical field of shale gas geology and development, in particular to a weak plane sliding friction characteristic simulation experiment device and method in shale gas development. The two test pieces are assembled in the positioning sleeve in a sliding manner, and two pore fluid channels extending at different angles are formed in the inclined surfaces of the test pieces so as to simulate a shale fracture weak surface; the liquid supply pump supplies liquid to the gap between the two test pieces through the liquid supply hole to simulate pore pressure; the pressurizing piece stretches into one end of the positioning sleeve and then abuts against the corresponding test piece so as to simulate ground stress; pressure is applied to the test pieces, the two test pieces slide through the inclined planes, the sliding friction coefficient change and the critical sliding water pressure are obtained through the shear displacement and the shear rate change of the test pieces, and the action process of shale weak plane sliding friction is reduced in a live-action simulation mode, so that the test results can be studied under different in-situ temperatures and stress states. The invention relates to a shale weak plane sliding friction model under the action of different occurrence shale weak planes, different fracturing fluids and pore pressures.

The present application provides a method for analyzing the permeability of a rock shear process, a computer device, and a storage medium. The method includes: obtaining a fractured rock particle model, the fractured rock particle model includes a first rock particle model and a second rock particle model, and there is a fracture between the first rock particle model and the second rock particle model; simulating the shear process of the fractured rock particle model according to a target confining pressure, obtaining a shear fracture surface between the first rock particle model and the second rock particle model when the shear displacement between the first rock particle model and the second rock particle model reaches a preset shear displacement; obtaining a seepage simulation parameter corresponding to the shear fracture surface, simulating the fracture seepage process of the shear fracture surface according to the seepage simulation parameter, and obtaining a seepage simulation result; determining the fracture permeability of the fractured rock particle model at the preset shear displacement according to the seepage simulation result. The shear seepage process of the rock can be simulated and calculated more accurately.

The present invention discloses a method for calculating the dynamic safety factor of a slope based on the shear displacement of a large rock mass, comprising the following steps: establishing a relationship between shear stress τ and the total area S of the rock interface; constructing a shear constitutive model of a small-scale rock sample by combining the classic structural plane shear stress-displacement curve and the Weibull distribution; converting the parameters in the shear constitutive model of the small-scale rock sample into corresponding large-scale rock mass parameters to construct a shear constitutive model of the large-scale rock mass; and bringing the real-time shear displacement of the sliding body into the shear constitutive model of the large-scale rock mass to obtain the dynamic safety factor of the slope. The present invention constructs a new shear constitutive model of a large-scale rock mass, and based on the expression of the shear constitutive model of the large-scale rock mass, brings the shear displacement of the sliding body into the shear constitutive model of the large-scale rock mass, so that the shear displacement of the rock mass can be used to calculate the dynamic safety factor of the slope.

The application provides a kind of pipe network engineering construction period intelligent remote monitoring method and system, related to underground space engineering safety technical field.The application obtains the transient dynamics parameters such as pipe network interface shear displacement, displacement rate and soil pore water pressure around pipe, and constructs system state vector and control vector by combining with construction machinery and grouting system operation boundary parameter, accurately reflects real-time dynamics state of pipe network;With pipe-soil coupling dynamics state evolution equation as constraint, with the minimum pipe network state deviation and control energy consumption as target to construct Hamilton function, and based on the pontryagin principle to solve the optimal control solution, realize the rapid deduction and global optimal control decision of pipe network deformation trend;Finally, the synchronous control instruction of mechanical frequency reduction and grouting pressurization is generated, which can complete active collaborative intervention in a very short time when high-frequency shear impact occurs, inhibit the transient shear deformation of pipe network interface, avoid interface shear separation damage, and reduce control energy consumption.

The invention relates to a combined in-situ testing device for bearing characteristics and shearing characteristics of a ground medium, and belongs to the technical field of ground mechanics testing. And the bearing characteristic experiment of the soft ground medium can be independently carried out. At the moment, the combined frame is only connected with the vertical loading assembly through threads, the pressure subsidence characteristic of a soft ground medium can be tested in a disc loading mode, the pressure subsidence characteristics of track shoes of different structures can also be tested, and therefore the bearing performance of the different track shoes can be evaluated. And the in-situ test can also be carried out on the pressure subsidence-shearing shear displacement characteristics of the track shoe under the combined loading working condition of vertical loading and shearing loading.

The invention relates to a viscoelasticity parameter detection method and system, and the method comprises the steps: fixing a to-be-detected sample on a substrate, pressing a pressure head into the sample, and maintaining the pressure head; wherein the sample is made of a viscoelastic material, and the effective action area of the pressure head is smaller than the in-plane size of the sample; applying a tangential load to the pressure head at a preset rate until a preset loading amount is reached, wherein the tangential load comprises shear force or shear displacement; keeping the preset loading amount for a preset time to obtain a relation curve of the tangential response of the sample and the time; and converting the relation curve into parameters in a constitutive equation, and determining viscoelastic parameters of the sample according to the parameters in the constitutive equation. By using the method disclosed by the invention, the original sample can be directly detected, the step of additionally preparing the sample is avoided, the sensitivity to the Poisson's ratio is remarkably reduced, and the viscoelastic parameter detection precision is improved.

The invention discloses a coal and rock mass tension-shear deformation decoupling monitoring method, system and equipment based on a generalized equivalent geometric model and a medium, and relates to the field of coal mine rock mechanics monitoring, the method comprises the following steps: collecting a Brillouin frequency shift signal of each analysis unit to obtain the total optical fiber axial strain of each analysis unit; for any analysis unit, obtaining a real dislocation displacement vector to be determined according to the initial length and the deformation length; decomposing a real dislocation displacement vector to be determined into a projection component and equivalent shear displacement along the axial direction of the optical fiber; forming an equivalent right triangle model based on the initial length, the deformation length, the projection component along the axial direction of the optical fiber and the equivalent shear displacement; obtaining a tension-shear coupling equation based on the equivalent right triangle model; and based on the total axial strain of the optical fiber of the analysis unit, determining equivalent axial strain and equivalent shear displacement by adopting a tension-shear coupling equation. According to the method, accurate decoupling of the complex tension-shear deformation field of the coal and rock mass is realized.

This invention provides a numerical simulation method and system for irregular contact between the inner wall and lining of a pipeline. The method includes: first, establishing a three-dimensional model of the pipeline and the lining, assembling and positioning them, and extracting the inner wall of the pipeline and the outer wall of the lining as the contact interface, and establishing corresponding contact pairs; defining tangential contact properties for the contact pairs, specifying a user-defined friction subroutine, and setting user parameter arrays and state variable arrays; then, constructing an interface friction constitutive model based on the frictional physics mechanism of the contact interface; during the finite element incremental analysis, obtaining the current normal pressure, shear displacement increment, state variables, and user parameters through the user-defined friction subroutine, calculating the interface trial shear stress of the current incremental step, and determining the actual shear stress and corresponding tangential stiffness of the interface based on the contact state; and writing the historical relevant data of the current incremental step into the state variable array for subsequent incremental steps to call. This invention can more reasonably characterize the interface shear stress, slip state, and contact evolution process.

The invention belongs to the field of geotechnical engineering, and provides a soil-rock interface shear statistical damage constitutive model construction method considering interface slippage dynamic change, and the method comprises the following steps: S1, constructing a soil-rock interface shear test platform, preparing soil-rock interface samples under different normal stress, moisture content and shear rate conditions, carrying out a shear test under the hydraulic coupling effect to obtain an interface shear stress-shear displacement curve; step S2, based on a statistical damage theory and in combination with a traditional contact surface statistical damage constitutive model, deriving a thickness-free soil-rock interface statistical damage constitutive model considering residual strength so as to represent damage evolution characteristics of the interface in a shear slip process; and S3, based on the shear stress-shear displacement curve, performing parameter identification on the thickness-free soil-rock interface statistical damage constitutive model considering the residual strength, and determining mechanical parameters in the model. According to the method, the calculation stability is improved, optimization is performed in combination with test data, and the engineering applicability is improved.

The invention relates to a microcosmic test device and method for measuring shear friction and anti-torsion characteristics of a microcosmic contact interface. Independent test modules for torsion test and shear test can be realized. The microcosmic test device comprises a support platform, a test unit (a torsion unit and a shearing unit) and a rotating unit. Compared with the prior art, normal displacement, shear displacement, friction coefficient and torsion angle of a contact interface under the single or coupling action of normal force, tangential force, torque and the like at the micro-nano scale are realized, and the relationship between force-displacement and torque-rotation angle is established; the microcosmic contact mechanical properties of a particle aggregate, a particle-plane, a plane-plane, a cemented sample interface and the like can be accurately reflected.

This invention relates to the field of marine geotechnical engineering technology, and provides a method and system for monitoring the shear state of calcareous sand based on acoustic emission centroid frequency. The method includes conducting a ring shear test on the calcareous sand to obtain the shear stress-shear displacement curve during the shearing process; attaching an acoustic emission sensor to the loading plate of the ring shear tester and using an acoustic emission monitoring system to collect acoustic emission signals during the shearing process; performing impact detection on the acoustic emission signals and extracting the waveforms of the impact signals; calculating the average centroid frequency of all impact waveforms within each preset time period; and based on the change in the average centroid frequency, analyzing the micromechanical mechanism of shearing in the calcareous sand and providing early warning of shear zone development and failure. This method can monitor the shear state of calcareous sand throughout the entire process and can be used for early warning of shear failure in calcareous sand foundations and other sandy soil materials in marine engineering.

The invention provides a rock joint dynamic shear mechanical parameter testing device and method.The device comprises a shear box structure, a bidirectional hydraulic loading system and a dynamic loading system, the shear box structure comprises a high-temperature shear box and a sealed shear box, and the bidirectional hydraulic loading system comprises a normal loading structure and a tangential loading structure; the high-temperature shear box or the sealed shear box is arranged in the normal loading structure and the tangential loading structure, and the dynamic loading system applies dynamic loading to the bidirectional hydraulic loading system. When the dynamic shear test of the rock joint test piece is carried out, the condition that the rock joint can better fit the real environment of the rock mass under the real-time high-temperature and water pressure environment conditions can be considered respectively, so that the test result is more accurate. The dynamic shear stress, the dynamic shear displacement and the dynamic normal displacement can be accurately acquired and calculated, and the impact applied by the dynamic loading device can enable the shear rate of the rock joint to reach the magnitude of 10m / s, which is far better than that of the existing technical equipment.

The invention relates to the technical field of geological disaster monitoring, and particularly discloses an automatic geological disaster monitoring device which comprises a bottom plate, a mounting frame is fixedly connected to the top end of the bottom plate, a displacement monitoring unit and a positioning unit are arranged in the mounting frame, and a mounting table is fixedly connected to the top end of the mounting frame. An environmental parameter monitoring unit and an integrated displacement, environment, geomechanics and other multi-dimensional monitoring unit are arranged on the upper side of the mounting table, so that the stability state of a geologic body is comprehensively reflected, and the limitation of single parameter monitoring is avoided; through a distributed optical fiber sensor, a GPS positioning module, a tilt angle sensor, a rainfall sensor, a temperature and humidity sensor, a soil pressure sensor, a pore water pressure sensor, a shear displacement sensor and the like, information in multiple aspects such as displacement, environmental parameters and geomechanical parameters of a geologic body can be acquired at the same time, so that the stability of the geologic body is evaluated more accurately and comprehensively; and a more reliable basis is provided for early warning of geological disasters.