142 results about "Shear strength test" patented technology

The invention discloses a testing method of the shearing resistance between a sealing gum and a stuck sample interface of a stuck base material, which manufactures the stuck base material into two samples, and a cavity with specified size is reserved in the middle for injecting the sealing gum, thus integrating the stuck base material and the sealing gum into a whole stuck sample which is placed in the environment with the temperature of 20 DEG C minus or plus 2 DEG C and the relative humidity of 65 percent minus or plus 5 percent for being conserved for 28 days, and the samples are respectively placed into an upper shearing box and a lower shearing box, positive pressure P1 is exerted on an upper part, and horizontal force P2 is exerted simultaneously. The shearing force exerted on the samples is measured by a dynamic meter 5. The shearing force P2 is exerted with specified loading rate, and until a shearing surface between the stuck base material and the sealing gum is destroyed, and the largest force measured by the dynamic meter 5 is the shearing resistant force. The value obtained by dividing the shearing resistant force by the area of the stuck sample interface is the shearing resistance between the bonding interfaces of the stuck base material and the sealing gum under the positive pressure P1. The testing method of the shearing resistance between the sealing gum and the stuck sample interface of the stuck base material has simple operation, convenient use and favorable popularization, has no need of new additional equipments, and has strong guidance to specific industrial practices.

The invention discloses an expansive soil slope shallow-layer damaged soil body shear strength test method. The method comprises the following steps: performing vacuum saturation on a test sample, applying normal stress corresponding to stress during shearing on the test sample in a water tank for water soaking curing saturation so as to enable the test sample to fully absorb water until the test sample is expanded completely, drying the expanded rest sample in a constant temperature oven until the test sample obtains the constant weight, and repeating the steps until preset drying and watering cycle times are finished, so that the effect of the drying and watering cycle of air can be truly reflected. According to the method, the effective normal stress contains relatively small effective normal stress capable of reflecting an actual stressing state of a soil body; the drying and watering cycle of the air is considered, and an equivalent load effect consistent to the normal stress during shearing is applied in the drying and watering cycle expanding process; shear strength test results are fitted by adopting an improved power function replacing a Moore Coulomp linear function, so that the shear strength, in the actual stress state, of the expansive soil slope shallow-layer damaged soil body can be truly reflected.

The invention discloses a temperature-suction-stress coupling multifunctional direct-shearing and single-shearing testing system and an operation method thereof. The temperature-suction-stress coupling multifunctional direct-shearing and single-shearing testing system comprises five parts including a control cabinet (1), a direct-shearing and single-shearing instrument (2), a diffused air bubble washing device (3), a temperature control device (4) and a computer (5), wherein the five parts are connected through a communication protocol; a testing process and data acquisition are controlled by utilizing the computer (5); manual testing control can also be carried out on the direct-shearing and single-shearing instrument (2), the diffused air bubble washing device (3) and the temperature control device (4) by adopting the control cabinet (1). The temperature-suction-stress coupling multifunctional direct-shearing and single-shearing testing system is applicable to soil body shearing strength tests and research under a temperature-suction-stress coupling effect; conventional consolidation, direct shearing and single shearing tests on a soil body can be effectively carried out, and consolidation, direct shearing and single shearing tests under a multi-field coupling effect of temperature, suction, stress and shearing waves can be realized; soil body shearing strength, a consolidation and sedimentation property and a soil-water characteristic curve under different environment conditions can be researched.

The invention relates to a geotechnical oblique shear strength test apparatus considering seepage flow impact. The geotechnical oblique shear strength test apparatus is characterized by comprising a reaction frame (1), a loading frame (2), a first servo motor (3), a second servo motor (4), a sample loading table (5), an upper shear box (6), a lower shear box (7), a rail trolley (8), a first vertical sliding rail (10), an upper box sample (11), a ball shaft row (12), a lower box sample (14), a horizontal sliding rail (17), a horizontal loading shaft (22), a vertical loading shaft (25), a second vertical sliding rail (30) and the like. According to the present invention, the apparatus is simple to manufacture, the measurement precision is high, the consolidation and oblique shear test requirement under different vertical stress loading and hydraulic gradient conditions can be met, the strain control type or stress control type loading can be performed, and the method can be used for the direct shear strength index obtaining of various rock soil bodies including coarse-grained soil, gravel soil, soil-stone mixing bodies and soil bodies encountered in the civil engineering or geological engineering under the seepage flow effect.

The present invention discloses a test and analysis method of geotechnical media tension-shear strength, and relates to geotechnical media tension-shear technology. The structure of the device is as below: a specimen (1) is installed in a holder (2); an axial pressure system (3) is connected to the specimen (1), and used for loading and recording axial pressure; an internal pressure system (4) is connected to the specimen (1), and used for loading and recording internal pressure and a tension-shear point capture device (5) is connected to the specimen (1) to achieve capture of the tension-shear point. The main steps of the method are as below: using a thick-walled cylinder-type crack instrument to achieve a geotechnical tension-shear failure test; calculating tension-shear strength; and drawing a tension-shear curve. The present invention has the advantages of simple experiment operation, high degree of automation and good repeatability. The method can be applied almost without modification to rock media compression shear strength test, and expands the scope of application of a traditional thick-walled tube fracturing experiment technology.

The invention discloses a detection method for detecting the brickwork shear strength of a cement mortar concrete porous brick wall. According to the method, the brickwork shear strength is detected based on the core drilling method. The brickwork is directly drilled to obtain a core sample. Arc surface-shaped holes in the core sample of the porous brickwork are filled densely by adopting the quick-hardening material. Meanwhile, the end bearing surface of the core sample is leveled and blocked up. After that, the shear strength test on the brickwork is conducted along the straight-joint cross section of the core sample. The shear strength of the brickwork core sample is converted into the shear strength of the brickwork. According to the technical scheme of the invention, the detection result of the method directly reflects the shear strength value the straight-joint cross section of the brickwork, so that the shear strength of the brickwork can be accurately reflected. Therefore, the method provides a basis for design-checking and calculation or identification and reinforcement. Meanwhile, the result is accurate and reliable, and the damage to the original structure is reduced, wherein a damaged part can be easily repaired. The above technique completes the field detection technology of brickwork projects and has good social and economic benefits. The correlation index of a relation curve between the shear strength of the core sample and the shear strength of a brickwork standard component is relatively high, and the average relative error of the curve is 13.7%. The relative standard deviation of the curve is 19.7%.

The invention discloses a shear test fixture. The shear test fixture can simultaneously satisfy the use of shear strength tests on Z-shaped and T-shaped samples. By using the flexible adjustment of a lower slide block selecting gaskets with different thicknesses, the fixture can be applied to samples with different thicknesses, thereby increasing the versatility of samples; and due to the addition of a fore applied spring and a positioning slide block, the force exerted on a sample in a clamped state can be adjusted, so that the elastic clamping of the sample is realized, therefore, the fixture has the advantages of ensuring that the sample does not slide in the process of testing, and the like.

The invention relates to an electric double-surface shear apparatus.An upper shear box, a middle shear box and a lower shear box are arranged on a foundation base, a bearing plate is arranged on the upper end surface of the upper shear box, a pressurizing plate is arranged on the bearing plate, an A pull-pressure sensor is arranged on the pressurizing plate and connected with an extension bar of a perpendicular pressurizing electric cylinder, and a perpendicular displacement sensor is mounted on one balanced vertical column and is in contact with the pressurizing plate; the middle shear box is further connected with a B pull-pressure sensor which is connected with a horizontal pressurizing electric cylinder on a slide rail base, and a displacement infrared emitter is arranged on the middle shear box; a control cabinet is further arranged on the foundation base, controls travel adjustment of all electric cylinders and processes sensor date in real time; the apparatus can be used for shearing strength test of an undisturbed soil sample, a disturbed soil sample and a soft rock sample, the whole test process comprises sample installation, sample performance and sample collection after test, and sample mounting and dismounting operation is convenient.

The invention relates to a test method for measuring the shear strength of welding spots and a dedicated tester thereof. Torsional moments, the rotational directions of which are opposite, are inputted into two sample plates, so that the two sample plates tend to oppositely rotate around mutually superposed rotational axes, the welding spots are located on the rotational axes, consequently, in the process of turning the two sample plates, the welding spots between the two sample plates are in a pure sheared state, the torsional moment applied on the welding spot by the sample plates in the process of applying test load on the welding spot and the pulling force applied on the welding spot by the sample plates in the process of pulling the welding spot apart are prevented from affecting a welding spot shear test, as a result, the obtained test result is more accurate, and the accuracy of the whole welding spot shear strength test is increased.

The method for making and testing rock compressive shear samples with discontinuous joints at high temperature in the present invention includes: 1) making rock compressive shear samples with discontinuous joints; 2) using rock compressive shearing samples with discontinuous joints The sample is tested for shear strength: a) Use the rock high-temperature triaxial compression test equipment to directly load the sample, carry out the rock compression test with discontinuous joints, and measure the shear strength with discontinuous joints; b) Use the rock high temperature The triaxial compression test equipment conducts the joint shear test under high temperature and high pressure conditions in the temperature and pressure chamber and the acoustic emission AE and CT scanning research during the test process: C) The shear plane of the rock compression shear sample with continuous joints is 10℃~ Testing of shear strength indicators (cohesion and internal friction angle) at 200°C. The invention can carry out acoustic emission (AE) test during sample compression and CT scanning test in compression process, has the advantages of exploring the effect of temperature and pressure conditions on joint properties, and makes up for the deficiencies of traditional rock samples.

The invention provides a tester for testing shear strength of frozen ice on a material surface, belongs to the technical field of cold region engineering, and is used for testing the adhesive shear strength of the frozen ice on a specific material. A lifting platform is positioned between a test bed and an operating platform, is in contact with steel tubes through bearings and slides on the steel tubes up and down; a screw reducer is connected with a force sensor through the test bed; the force sensor is connected with the lifting platform; a displacement sensor is positioned on the test bed and the lifting platform; the operating platform is fixed on a base and is parallel to the base; a fixture is a stainless steel block; a hollowed area as a test sample forming area is formed in the middle of the fixture; the upper end of the fixture is connected with the lifting platform; one end of a material to be tested is fixed on the operating platform, and the other end of the material to be tested is buckled on the fixture. The test can test the adhesive shear strength of the frozen ice and any material surface; through the displacement sensor, a deformation situation at an adhering position in a stretching process is measured; the adhesive shear strengths of the frozen ice at different loading rates can be obtained.

The invention discloses a discrete element numerical simulation method for viscous sandy soil hydraulic erosion damage. The method comprises the steps of:establishing an initial calculation space areaand a viscous sandy soil numerical model; initializing a numerical model and balancing stress; compiling a strength degradation criterion linear bonding contact model based on a time effect to simulate a clay phase between aggregate particles in the viscous sandy soil; selecting a contact model as a mesomechanics model of contact between aggregate particles, and valuing mesoscopic parameters of the contact model; calibrating the numerical model through a direct shear strength test; establishing a flow field to simulate the hydraulic erosion damage process of the viscous sandy soil; and obtaining a numerical simulation result of the hydraulic erosion damage test. According to the method, the viscous sand hydraulic erosion damage is simulated through the discrete elements, the thought is simplified, the viscous sand hydraulic erosion damage process can be truly simulated on the mesoscopic level under the conditions that the calculated amount is reduced as much as possible and the calculation efficiency is improved, the migration situation of soil particles is observed and recorded, and the result is accurate.

The invention discloses a method for determining reasonable compacting temperature of a modified asphalt mixture, and belongs to the field of road engineering. The method comprises the following steps: using an impacting penetration test to simulate a compacting shear rate and carrying out a temperature changing equivalent shear strength test on the mixture with the degree of density in an initial compacting stage; and calculating the reasonable compacting temperature of the modified asphalt mixture from a reasonable compacting temperature range of a known matrix asphalt mixture according to an equal penetration depth-temperature relation. The method provided by the invention is quick to operate and simple to control the test conditions, the test period is greatly shortened, and the method has application and popularization values.

The invention relates to a shear strength tester and a method for testing the shear strength, belonging to a special instrument and a method for testing the cementation shear strength between a strip and an original concrete structure when the concrete structure adopts a superficial layer to inlay high-strength strip or the high-strength strip is bonded on the surface in an engineering structure reinforcing and reforming project. The tester comprises a dynamometry link, a shear bracket and a scaling instrument. The end part of the shear bracket is tensioned by screwing a bolt of the dynamometry link; the strip after bonding is sheared by an actuating boot to cement with the concrete interface; the size of the shear force is tested by adopting a pull pressure sensor arranged inside the dynamometry link; and the maximum shear force is displayed by the scaling instrument. The anchoring length can be theoretically calculated by the shear strength tested by the device. The device has the advantages of simple structure, accurate actuation, simple and convenient operation, easy maintenance, and the like, does not need external power source and can be used under various environments.

The invention discloses a box type sampling shear strength testing method, which comprises: a, a positioning operation, wherein the positioning operation comprises a horizontal positioning operation and a vertical positioning operation; and b, a shear strength measurement operation, wherein the positive rotation starting of the drive motor of a drive mechanism is controlled by a control circuit, a cross plate test assembly is driven to rotate to preset the angle value, the torque value applied on the cross plate is real-timely collected through the control circuit during the rotation process and the corresponding rotation angle value is combined, and the curve map of the shear stress along with the rotation angle change is output and displayed; and after the peak value appears for 1 min in the curve map, the experiment is stopped and the peak value is determined as the shear strength value of the clay to be tested. According to the present invention, the box type sampling shear strength testing method relates to, but is not limited to clay test equipment; and with the box type sampling shear strength testing method, the drawbacks in the prior art can be effectively overcome, the shear strength test of the soft clay with the high water content can be achieved, and the precision of the final test result can be effectively ensured.

The invention provides a structural plane shear strength size effect testing device equivalence testing method. A testing device consists of n direct shear apparatuses. The equivalence testing method comprises the following steps of: (1) taking the sample size Lx x Lx as the overlapping sizes of two direct shear apparatuses, firstly carrying out shear strength tests on at least 5 groups of same structural planes with the sample size being Lx x Lx by adopting the nth direct shear apparatus to test the shear strength with the preset assurance rate; (2) then carrying out the shear strength tests on at least 5 groups of same structural planes with the sample size being Lx x Lx by adopting the (x+1)th direct shear apparatus; (3) carrying out equivalence tests on the shear strength of the structural planes of rock mass with the same sizes tested by the two direct shear apparatuses; (4) by adopting the methods in the steps (1), (2) and (3), respectively carrying out the equivalence tests on the overlapped samples of the n direct shear apparatuses. The structural plane shear strength size effect testing device and the equivalence testing method can be used for effectively testing the equivalence of testing results of all the direct shear apparatuses, and are strong in operability and low in cost.

A portable soil body in-situ shear test device includes four parts: an active force system forming arranged externally, a passive shear system and an electromagnetic loading system forming arranged internally, and a ring knife system arranged at a bottom. Compared with the conventional in-situ soil shear strength test device and test method, the present invention is convenient to install and carry as well as simple to operate, and has strong applicability. The present invention is suitable not only for layered soils with large cross-plate shear test errors, but also for soils with different consolidation degrees at various sites and various terrains. A test method adopting the device can simulate the shear strength of the soil mass under different overburden loads without disturbing the mechanical properties of the in-situ soil mass, which has high promotion value in the test of in-situ soil shear strength.

The invention provides a preparation method of an unconventional natural gas well fracturing physical simulation sample, which comprises the following steps: 1, determining the uniaxial compressive strength and tensile strength of a reservoir shale test piece, and selecting cement satisfying the strength grade requirements; 2, placing two sandstone sheets on the two sides of a concrete mold, and pouring the stirred mixture of the cement, the quartz sand, the stones and the water between the two sandstone sheets; 3, removing the mold after curing and molding to obtain a simulated multi-layer sample, and performing bedding surface shear strength test on the sample to determine the shear strength; and 4, drilling a simulated borehole in the center of the sandstone thin plate, and cementing the simulated wellbore to obtain the multi-layer sample with the simulated wellbore. The unconventional natural gas well fracturing physical simulation sample is prepared by combining the blended similar material and the natural sandstone, the fracturing test piece more conforming to the unconventional natural gas condition is prepared, and the expansion mechanism of cracks in the direction perpendicular to the bedding direction in the unconventional natural gas well fracturing process can be more deeply studied.

The invention provides a testing method capable of realizing whole-process tracing of a shear strength test of a structural plane. The method comprises the following steps: (1) acquiring a model by three-dimensional scanning of an original rock structural plane, and acquiring the morphology changes of a three-dimensional surface in the progressive process of shearing; (2) based on a whole-processvisualization testing method, testing a transparent sheared sample by using a direct shear tester for indoor rock structural planes; (3) recording test data and carrying out multi-directional CCD photographing synchronously; (4) comparing the morphology of the structural plane by regions, and visually describing the surface damage conditions of the structural plane in each region, respectively; (5) integrating each shooting region and visually describing the location, number and expansion of cracks; and (6) carrying out shear test research under the conditions of different surface morphologies and different stresses. The testing method provided by the invention analyzes the gradual change process of the shear morphology characteristics of the structural plane and the extension and changerules of cracks around the structural plane under the conditions of different structural plane morphologies and different stresses.

The invention discloses a shear strength testing device and a shear strength and static cone penetration testing method thereof. The shear strength testing device comprises a base, a penetration system, a rotating system and a measuring system, wherein the penetration system is arranged on the base; the rotating system is connected with the penetration system, and the measuring system is connectedwith the rotating system. The measuring system comprises a probe rod, one end of which is connected with the rotating system, and the other end of which is connected with the conical head, and a conical head, which comprises a first conical head and a second conical head which are connected to the probe rod in a replaceable manner; an annular pressure gauge is arranged on the middle circumferenceof the first conical head; the fan-shaped conical plates of the second cone head are uniformly and vertically arranged on the circumference of the cone head body. The invention has the advantages that the data of the cohesion force and the friction angle of the soil body on the spot can be quickly and conveniently obtained; the problems that the traditional cross plate shearing test can only be used for measuring the soft soil layer and the cohesive force and has narrow application range are effectively solved; and the device is simple in structure, small in volume and convenient to carry anduse.

The invention discloses an evaluation index for the anti-shearing performance of a waterproof bonding layer paved on a bridge deck. According to the evaluation index disclosed by the invention, freezing and thawing cycle lateral stiffness ratio LSR is adopted for evaluating, wherein LSR is not smaller than 85%, LSR is the ratio of the lateral stiffness of a freezing and thawing cycle test specimen to the lateral stiffness of an unfreezing and un-thawing cycle test specimen, the lateral stiffness LS is the ratio of the peak load to the maximum relative displacement among layers when a waterproof bonding layer of tar sands or modified tar sands is subjected to shear failure, and the shear force and the displacement in LS index among the layers can be accurately tested, the operation is simple and convenient, thus popularization is easy. According to the evaluation index disclosed by the invention, the defects that in the current regulation of China, the triaxial compression shear strength test is difficult to operate and complicated in calculation, and the shear strength parameters c and phi have small difference are overcome; the lateral deformation resistance of the waterproof bonding layer paved on the bridge deck can be truthfully reflected; the LSR is also suitable for evaluating the anti-shearing performance of a bituminous mixture; the LSR integrates high temperature property, low temperature property and high stability of the bituminous mixture, and can comprehensively evaluate the pavement performance of the bituminous mixture.

The invention relates to a pre-applied shearing strength test piece, a preparation device and a preparation method for a test piece and a splitting test method. The invention aims to overcome the defects that only a single-axial tensile pressing condition is considered and the shearing strength is difficult to consider on the basis of the traditional high pressure water splitting simulation test design method and traditional high pressure water splitting simulation test design device and the test piece only can be normal concrete. The test piece has an extending direction; an inclined layer is arranged on the middle position along the length direction of the extending direction; an included angle alpha is formed between the inclined layer and a preset direction; a preset crack is arranged on the inclined layer; the preset crack is communicated with the exterior of the test piece through an interface channel. According to the test method, the preset crack is filled with high pressure water till the preset crack is split and a single-shaft test device is used for applying the shearing strength to the test piece. The test piece, the device and the test method provided by the invention can consider the influence of the shearing strength of the roller compacted concrete, so that the working condition of the roller compacted layer of a roller compacted concrete high-dam under the effect of high pressure water can be effectively simulated.

The invention discloses a rock field shear strength test device and method, and which are suitable to be used in the field of rock detection. The rock field shear strength test device comprises a shear test head, wherein a shear stress loading pull rod is arranged at a tail end of the shear test head; the shear test head is connected with a servo oil pump which is arranged outside a step-shaped borehole through an oil circuit; a borehole orifice baffle plate, a shear stress loading jack and a shear stress loading jack locking nut are arranged at a tail end of the shear stress loading pull rod in sequence; the shear stress loading jack and the borehole orifice baffle plate are extruded and fixed on a rock at a borehole orifice; a shear displacement test device is arranged between the tail end of the shear stress loading pull rod and the borehole orifice baffle plate; the servo moil pump and the shear displacement test device are connected with a stress-displacement data collection and display system through circuits. Shear force is applied to the borehole by the shear test head, and the cohesive strength and the internal friction angle of a tested object are obtained by regression fitting according to a Mohr-coulomb yielding criterion. The rock field shear strength test device has a simple structure, is accurate in tests, and can be used for monitoring a displacement value all the time in a pulling process.

The invention provides a T-type high energy beam welding joint shear strength test piece and a manufacturing method of the T-type high energy beam welding joint shear strength test piece. The T-type high energy beam welding joint shear strength test piece is applied to a shear-bearing capacity test of a T-type high energy beam overlap joint welding line with a greater difference between material wall thicknesses at two sides; the shear strength test piece comprises two or three test piece upper plates and one test piece lower plate; the materials and the thicknesses of the test piece upper plates are the same and the test piece upper plates are on the same plane; the test piece upper plates are respectively welded on the test piece lower plate by two welding lines through high energy beam welding; the two welding lines are parallel; the manufacturing method comprises the following steps of: determining the materials of the test piece according to parent materials at two sides of the welding lines in the product; assembling the test pieces to be welded at the upper and lower sides in place; welding two parallel welding lines with the same parameters on the test pieces; cutting sheet materials at upper sides of the middle parts of the two welding lines; and machining a certain quantity of dynamic test pieces on the test piece according to a GB/T2651-2008 Welding Joint Tensile Test Method.

The invention belongs to the technical field of coating shearing strength tests, and particularly relates to an aluminum sheet substrate for a coating shearing strength test and a test sample thereof. The aluminum sheet substrate comprises an inlaying groove which is formed in one side of the aluminum sheet substrate and used for inlaying a glass plate or porcelain plate and one or more movable clamping buckles used for clamping the glass plate or porcelain plate after the glass plate or porcelain plate is placed in the inlaying groove; each movable clamping buckle comprises a movable clamping sheet which is fixed on one side of the inlaying groove and can rotate in a pivot mode and fixing buttons fixed on the other side of the inlaying groove. The test sample is composed of two aluminum sheet substrates of which parts are overlapped, the aluminum sheet substrates are arranged in the mode that the inlaying grooves are opposite, the glass plates or porcelain plates are inlaid into the inlaying grooves of the aluminum sheet substrates, and a to-be-tested coating used for bonding parts of the glass plates or porcelain plates together is applied between the glass plates or porcelain plates which are inlaid into the inlaying grooves of the aluminum sheet substrates. According to the aluminum sheet substrate for the coating shearing strength test and the test sample thereof, the test torque is decreased, and the substrate is made to be not prone to deformation, convenient to disassemble and capable of being repeatedly used and not need to be bonded.

The invention provides a method for detecting the shearing strength of an interlayer bonding surface of rock filled concrete of constructional engineering. After a test piece is manufactured through excavation in a rock filled concrete dam or foundation of the constructional engineering, vertical loading and horizontal loading are applied to the test piece gradually and respectively, the linear regression coefficient is determined according to the computational formulas of normal stress and shearing strength on a shearing surface, and the shearing strength of the interlayer bonding surface of the rock filled concrete dam can be calculated. According to the method, the test piece is excavated on a structural member entity, the test piece is subjected to shearing strength test by a jack, force applied to the test piece is pure shearing force, the concrete failure surface is consistent to the direction of the anti-shearing force, the influence factors in a testing process are reduced, the testing precision is improved and the testing process is simple and easy.

A polyurethane foaming gap filler and its use in repairing ancient mural hollow drum in wet coffin chamber are disclosed. It adopts salt corrosion test, damp-heat ageing test, freeze-thaw circulation test, adhesive strength test, tensile strength test, shearing strength test, porous and air-permeability test, and artificial accelerating ageing test. It has high soluble slat content, the adhesive strength minimum value is 0.004 MPa, and greater the weight of mural. It has better binding effect and can be used to protect relics.