819 results about "Shear strength" patented technology

The invention relates to the field of tunnel engineering geology and support design, and discloses a weak surrounding rock tunnel deformation risk discrimination method based on shear expansion-shear constitutive, which comprises the following steps: constructing a nonlinear coupling model between a shear expansion angle and shear stress, normal stress and joint parameters, and obtaining the shear expansion angle; establishing a volumetric strain rate discrimination formula; inverting an initial crustal stress tensor field; reconstructing an irregular tunnel boundary; constructing a risk level discrimination model, and outputting a risk level; supporting schemes such as supporting rigidity, anchor rod parameters and spraying layer thickness are matched according to the risk grades; establishing a model to predict a risk trend; a support adjustment suggestion is generated; collecting monitoring data to dynamically correct model parameters; and all the modules are integrated in a deployment system. According to the method, the coupling relation between the shear expansion angle and the shear strength is introduced, the coupling type constitutive discrimination model is established, the risk grading system and the support correction strategy associated with the support response are constructed, and active early warning of the high-risk section and dynamic adjustment of the support rigidity are achieved.

The invention discloses an explosive welding method for preparing a super-thick large-area composite plate based on a nickel-based alloy plate. A steel plate serves as a base plate, a plurality of supporting blocks are laid, a nickel alloy plate is placed on the supporting blocks, then powdery emulsion explosive is laid, a detonator is placed, and finally the super-thick large-area nickel-based alloy composite plate is prepared after explosive cladding and detection are qualified. According to the explosive welding method for preparing the super-thick and large-area composite board based on the nickel-based alloy board, explosive cladding of the super-thick and large-area nickel-based alloy composite board is achieved, the fitting rate, the shear strength and other performance of the composite board can meet the requirements, and the mechanical performance and the corrosion resistance can meet the requirements of development of the industries such as equipment manufacturing and chemical engineering.

The invention relates to the technical field of defect detection, and discloses a Babbitt metal coating surfacing thin-wall layer defect detection method and device. The method comprises the following steps: carrying out multi-source detection data acquisition, multi-domain transformation and filtering enhancement on a babbitt metal coating, and obtaining preprocessed multi-source initial coating detection data to carry out interface-tissue-defect mapping, so as to obtain unified representation of an internal tissue structure of the coating; performing progressive fusion of a coating depth structure and extraction of coating defect morphology and structural features on the unified feature representation to obtain preliminary defect semantic features, and performing feature weighting calculation of defect morphology on the preliminary defect semantic features to obtain initial defect semantic features; and carrying out bearing strength and shear strength calculation and fatigue life prediction on the initial defect semantic features to obtain a final detection result. According to the method, the defects of the thin-wall layer coated and surfaced by the babbitt metal can be efficiently and accurately detected.

The disclosure discloses a method for strengthening shear strength of a RC beam with a compressed steel bar, including step one: analyzing and concluding that the compressed steel bar has a positive effect of on shear strength of the RC beam via experimental testing and / or establishing a truss model; step two: carrying out a finite element simulation; step three: comparing a result obtained by the finite element simulation with that obtained by the experimental testing, to verify a reliability of the finite element model; step four: systematically researching a comprehensive impact of a reinforcement ratio of the compression steel bar, a stirrup ratio ρsv, a reinforcement ratio ρst of a tensile longitudinal steel bar, a shear span ratio / and a concrete strength grade (fco) on the shear strength of beam; and step five: obtaining a mathematical model of an increment of shear strength via regression analysis.

The invention discloses a preparation method of a medium-entropy alloy and stainless steel explosive welding composite board, and belongs to the field of metal-based composite material processing. The preparation method specifically comprises the following steps: polishing the medium-entropy alloy and the stainless steel to remove oil stains and oxides on the surfaces of the medium-entropy alloy and the stainless steel; a low-carbon steel anvil serves as a base plate, stainless steel serves as a base plate, a medium-entropy alloy serves as a compound plate, a corrugated board serves as a buffer layer of explosive and the compound plate, and metallurgical connection of the medium-entropy alloy plate and the stainless steel plate is achieved through low-detonation-velocity high-brisance mixed explosive. The interface bonding rate of the obtained composite board is larger than 98.8%, the yield strength is larger than 620 MPa, the tensile strength is larger than 735 MPa, the percentage elongation after fracture is larger than 40%, and the interface shear strength is larger than 300 MPa. The process is simple and convenient, and is suitable for industrial production.

The invention belongs to the technical field of gate shaft construction, and particularly relates to a one-time forming pouring system and a one-time forming pouring method. The gate groove formwork and the vertical shaft sliding formwork assembly in the one-time forming pouring system can move in the depth direction of the gate shaft and jointly define a pouring ring, and when the strength of hydraulic concrete structures corresponding to the vertical shaft sliding formwork assembly and the gate groove formwork reaches the demolding strength, the gate groove formwork and the vertical shaft sliding formwork assembly are separated. The positions of the vertical shaft sliding formwork assembly and the gate groove formwork can be adjusted through the lifting device and the hoisting device, so that the pouring space rises in the depth direction of the gate shaft, continuous pouring of the hydraulic concrete structure is met, pouring of the hydraulic concrete structure does not need to be conducted step by step, joints are avoided, and the construction efficiency is improved. The integrity and shear strength of the hydraulic concrete structure are improved, so that the construction quality of the hydraulic concrete structure in the gate shaft is ensured, and meanwhile, the construction difficulty is reduced.

The invention discloses a rolled extra-thick stainless steel composite plate and a production method thereof. Base layer steel comprises the following chemical components in percentage by weight: 0.12-0.16% of C, 0.18-0.30% of Si, 1.30-1.50% of Mn, less than or equal to 0.012% of P, less than or equal to 0.003% of S, 0.02-0.04% of Alt, 0.15-0.25% of Cr, 0.50-0.60% of Mo, 0.55-0.65% of Ni, less than or equal to 0.10% of Cu, less than or equal to 0.02% of Nb, less than or equal to 0.0010% of B and the balance of Fe and inevitable impurity elements. The cladding stainless steel comprises the following chemical components in percentage by weight: less than or equal to 0.03% of C, less than or equal to 0.75% of Si, less than or equal to 2.00% of Mn, less than or equal to 0.035% of P, less than or equal to 0.015% of S, 8.0-12.0% of Ni, 18.0-20.0% of Cr, less than or equal to 0.10% of N and the balance of Fe and inevitable impurity elements; the process route comprises the steps of blank welding compounding, vacuumizing, controlled rolling and quenched-tempered heat treatment. The SA533B CL1 + SA240304L stainless steel composite plate with the thickness of 62-69 mm is produced, the inspection yield strength is larger than 345 MPa, the tensile strength is larger than 550 MPa, the impact energy at the temperature of 10 DEG C is larger than or equal to 200 J, the shear strength is larger than 310 MPa, and the intergranular corrosion crack rate is 0.

The invention discloses a preparation method of a CoCrNi medium-entropy alloy and Q235B steel explosive welding composite board, which comprises the following steps of: annealing a CoCrNi medium-entropy alloy board, sequentially laying sandy soil, an anvil, a Q235B hot-rolled steel plate, a support column, a medium-entropy alloy board, kraft paper and explosive from bottom to top on an explosion field, and performing explosive welding to obtain the CoCrNi medium-entropy alloy and Q235B steel explosive welding composite board. The detonation velocity of the explosive ranges from 2500 m / s to 3000 m / s, and the brisance of the explosive ranges from 18 mm to 22 mm. According to the method, metallurgical bonding of the CoCrNi medium entropy alloy and the Q235B steel plate is achieved, the interface bonding rate of the obtained composite plate is larger than 99.2%, the yield strength is larger than 420 MPa, the tensile strength is larger than 500 MPa, the percentage elongation after fracture is larger than 35%, and the interface shear strength is larger than 200 MPa. The method is simple in process and suitable for industrial production.

The invention discloses an ultrahigh-strength prestressed concrete pipe pile and a preparation method, and relates to the technical field of building materials. The ultrahigh-strength prestressed concrete pipe pile comprises a core layer which is composed of 1.0%-2.0% by volume of chopped basalt fiber reinforced concrete, the fiber length is 8-12 mm, the diameter is 15-20 microns, and the compressive strength is larger than or equal to 130 MPa; the transition layer is composed of hybrid fiber reinforced concrete with the volume fraction of 3.0%-4.0%, steel fibers account for 60%-75%, polyethylene fibers account for 25%-40%, the length-diameter ratio of the steel fibers is 50-80, and the tensile strength is larger than or equal to 1200 MPa. Through gradient fiber reinforced structure design and preparation process innovation, the mechanical property, the production efficiency and the environmental friendliness of the prestressed concrete pipe pile are synergistically improved. Firstly, in the aspect of mechanical properties, the compressive strength is made to break through 130 MPa through the synergistic effect of the core layer basalt fiber and the high-activity superfine slag powder and is improved by 30% or above compared with a traditional C100 pipe pile, and meanwhile the shear strength is improved to 18 MPa or above through a transition layer steel-polyethylene hybrid fiber system.

The present application provides a split bolt, which relates to the field of building technology. The split bolt comprises: a base and a plurality of split parts, the split parts comprising a first part and a second part, one end of the first part is connected to the second part, the other end of the first part is connected to the base, the first parts of the plurality of split parts and the base constitute a bolt rod, the second parts of the plurality of split parts constitute a bolt cap, and there is a gap between adjacent split parts, and the gap is filled with an elastic partition material. The split bolt greatly improves the shear strength of the bolt by increasing the diameter of the base, meeting the shear force requirements between steel and high-strength or ultra-high performance concrete. The upper split part is used to meet the requirement that "the length of the weld of the cylindrical head welded nail connector should not be less than 4 times its rod diameter", and maintain good ductility. It has the advantages of avoiding the group nail effect, convenient construction, reducing the number and height of the bolts, and increasing the shear bearing capacity without reducing the ductility.

The invention belongs to the technical field of titanium-steel composite plates, and particularly relates to a production process for preventing grain growth of a titanium-steel composite plate, which comprises the following steps: roughening the lower side surface of a titanium plate and the upper side surface of a steel plate by adopting a sand blasting process; an additive is sprayed to the upper side face of the steel plate and the lower side face of the titanium plate, the additive comprises boron powder and a binding agent, graphite foil is laid on the upper side face of the steel plate sprayed with the additive, the titanium plate sprayed with the additive is stacked on the steel plate, and the graphite foil is clamped by the upper side face of the steel plate and the lower side face of the titanium plate to prepare a composite plate blank; sealing the edge part of the composite plate blank by using a sealing material; the production process comprises the following steps: heating a composite plate blank through a heating furnace, rolling and cooling the heated composite plate blank, straightening the composite plate blank through a straightening machine, and trimming the straightened composite plate blank to obtain the titanium-steel composite plate. And the bonding strength and the shearing strength of the titanium steel composite plate are improved.

The invention discloses a production method of a T2+Q355B copper steel rolled composite plate. The technological process comprises the steps of assembling, heating, rolling, stack cooling, finishing, flaw detection and warehousing. A T2 + Q355B copper steel rolled composite plate with excellent bonding strength, mechanical property and conductivity is obtained by adopting a vacuum rolling composite technology, a symmetric assembly technology and a low-speed deformation technology and utilizing wide and thick plate production line equipment and technical advantages, the thickness of a base material ranges from 5 mm to 40 mm, the thickness of a composite layer ranges from 1 mm to 20 mm, the width is smaller than or equal to 3600 mm, the yield strength is larger than or equal to 250 Mpa, the tensile strength ranges from 350 Mpa to 600 Mpa, the shear strength is larger than or equal to 120 Mpa, and the composite layer T2 copper conductivity IACS is larger than or equal to 85%. The intergranular corrosion crack rate is 0. The product can be widely applied to the fields of high-voltage electric appliances, ship manufacturing, new energy equipment and the like, and has the potential of replacing traditional products.

The invention discloses a method for constructing a shear constitutive model of a discontinuous structural plane. The method comprises the following steps: acquiring a peak value and a shear strength parameter in a residual stage; obtaining the initial rock mass shear strength tau of the discontinuous structural plane based on a Jennings criterion; introducing coefficients Xij and Xir to respectively adjust the normal stress at the joint and the rock bridge, and meanwhile, introducing a coefficient Omega to adjust the cohesive force of the rock bridge to obtain the rock mass shear strength tau of the adjusted discontinuous structural plane; based on a Lajtai rock bridge failure theory criterion, obtaining failure criteria of three discontinuous structural surfaces of tension, shearing and strength failure; and obtaining a shear constitutive model of the discontinuous structural surface corresponding to the rock bridge under the tension failure condition, the shear failure condition and the strength failure failure condition. According to the method, the shear constitutive model of the discontinuous structural plane is established, the shear behavior characteristics of the discontinuous structural plane can be effectively described, and the practicability of the constitutive model is effectively improved.

Building techniques and structures to fabricate components of expanded polystyrene (EPS) for assembly into a building include structures and ways to make keys to provide shear strength between components, structures and ways to minimize infiltration paths between walls and floors and walls and roof while reducing labor, material wastage and logistics complications. By way of example, components are strategically cut from a block of EPS using a hot wire moving through the block to cut components to a desired and novel configuration.

Provided are a solder alloy, a solder ball, a preformed solder, a solder joint, and a circuit, which are excellent in wettability and shear strength, suitable in failure mode, capable of suppressing the growth of an intermetallic compound at a bonding interface even after multiple reflow soldering, excellent in drop impact resistance, and suitable in the shape of a bump. The solder alloy has an alloy composition comprising, in mass%, 0.10 to 3.00% of Ag, 0.80 to 6.00% of Cu, 0.08 to 0.60% of Ni, 0.0010 to 0.0150% of Ge, and the balance of Sn. It is preferable that the alloy composition further contains 0.1% or less of at least one of Bi, Sb, In, Zn, Ga, Mn, Cr, Co, Si, Ti, and rare earths in total.

The invention discloses a gabion gabion net cage system for reinforcing a high-fill embankment of an expressway, belongs to the technical field of gabion gabion net cages, and solves the problems that in the prior art, external loads are resisted only through self-strength, and the gabion gabion net cage system and a filling body are difficult to form a synergistic deformation whole, so that the structure is cracked and fails. The system comprises an excavation roadbed, at least one group of filling slope foundations, gabion gabion gabion net cages and backfill discrete materials, according to the gabion gabion gabion grid net cage, through the synergistic effect of tensile resistance of the steel wire mesh and shear resistance of the block stones, the gabion gabion gabion grid net cage and the filling discrete material form a flexible-rigid composite structure, so that the high tensile property of the steel wire mesh can effectively restrain horizontal displacement and deep slippage of the filling material, and deformation of a side slope along a potential slippage face is restrained; and the gradation matching performance of the block stone filling structure and the backfill discrete materials enhances the occlusion effect between the materials, and the shear strength and the overall rigidity of the slope are remarkably improved.

The invention discloses an angle steel connecting piece shear strength prediction method and system based on a physical information neural network, electronic equipment and a storage medium thereof. The method comprises the following steps: establishing a database containing a plurality of groups of test data based on a numerical simulation result of an angle steel connecting piece finite element model verified by a push-out test; embedding an angle steel connecting piece shear bearing capacity physical constraint condition based on an elastic foundation beam theory into a loss function of the data-driven neural network model DNN; training the neural network embedded with the physical constraint condition by using a database, and adjusting and selecting a physical item weight factor and a model learning rate so as to construct a shear bearing capacity prediction model of a physical information neural network (PINN); predicting the shear strength of the angle steel connecting piece by using the trained physical information neural network (PINN) shear capacity prediction model; according to the prediction method and system, the electronic equipment and the storage medium thereof provided by the invention, the accuracy and reliability of the shear resistance prediction of the angle steel connecting piece can be improved.

The invention is suitable for the technical field of structural design, and provides a concrete interface shear strength prediction method, device and equipment and a storage medium, and the method comprises the following steps: obtaining the shear strength and concrete parameters of a concrete interface; establishing an initial LightGBM model, recording the initial LightGBM model as a first model, and preprocessing shear strength and concrete parameters to obtain a training set and a test set; based on a collaborative group optimization algorithm and a genetic algorithm, optimizing hyper-parameters of the first model to obtain a target hyper-parameter set; applying the target hyper-parameter set to the first model to obtain a second model, and training the second model based on the training set and the test set to obtain a shear strength prediction model; and inputting the concrete parameters of the target concrete interface into the shear strength prediction model to obtain a shear strength prediction value of the target concrete interface. According to the method, the shear strength of the concrete interface can be accurately predicted under the condition of complex working conditions.

The invention discloses a V-shaped slope stability calculation method and system, and relates to the technical field of open-pit mining. On the basis of a three-dimensional numerical simulation technology, the damage mode of the sliding body is judged, a spatial form equation of a potential sliding body is determined firstly, then the sliding body is divided into micro-strip columns in a regional mode, the stress state of the micro-strip columns is solved through a constitutive relation and a static balance condition, and the force of each row of micro-strip columns is superposed in the direction of a main sliding surface; and obtaining two-dimensional equivalent shear strength parameters with a three-dimensional effect on each row of main sliding surface micro-strip columns by using an equivalent thought, and then deducing a three-dimensional V-shaped slope stability coefficient by using a rigid body limit equilibrium method. According to the method, the problems of high calculation cost, difficulty in parameter determination and complex calculation process in a traditional slope three-dimensional stability calculation method are avoided, the problem of three-dimensional stability of the slope in the special form is solved, a more reliable theoretical technology is provided for design, mining, prevention and treatment of the slope, and the method is worthy of popularization and application. The method has important practical significance for guaranteeing safe and efficient production of mining.

The invention discloses a method for evaluating damage evolution of an underground structure under the action of a sudden explosion load, and relates to the technical field of civil engineering and engineering disaster prevention, and the method is characterized by comprising the following steps: S1, simulating the underground structure based on an explosion load, a geometric boundary and material parameters, and constructing a unified constitutive model; and S2, introducing a pressure-related strength criterion of a Dwark-Prasugrel criterion into the unified constitutive model so as to describe the influence of confining pressure on the shear strength. The technical problem to be solved by the invention is to provide the method for evaluating the damage evolution of the underground structure under the action of the burst explosion load, so that the key pain points such as pressure correlation, high strain rate effect, material random discreteness, damage softening energy consistency and the like are difficult to consider at the same time in the existing analysis method. A set of damage evolution evaluation method and implementation system which can be implemented from the material level to the structure level is established, and quantitative prediction and engineering grading judgment of the whole process of crack initiation, expansion to instability failure of the underground structure are supported.

The invention relates to the technical field of metal material fracture resistance testing, in particular to a prediction method for interface fracture toughness of a polar region ship composite steel plate, which comprises the following steps: S1, preparing a composite steel plate; s2, carrying out a three-point bending fracture test; s3, performing an interfacial shear strength test; s4, data analysis and model construction: performing fitting analysis on the obtained fracture toughness data of the large-size sample and the obtained shear strength data of the small-size sample, determining undetermined parameters, and constructing a mathematical model between the interface fracture toughness and the interface shear strength of the composite steel plate; and S5, verifying the accuracy of the model. According to the method, the mathematical model is established by analyzing the correlation between the shear strength measured by the small-size interface shear sample and the fracture toughness measured by the large-size fracture sample, and the model has the advantages of simplicity in construction, rapidness in use and the like, so that rapid prediction and evaluation of the fracture toughness of the composite steel plate are realized, the test process is greatly simplified, and the test efficiency is improved. And the research and production efficiency is improved.

The invention discloses a hole slag back pressure backfilling and roadbed structure integrated construction technology, and belongs to the technical field of road construction. Comprising the following steps: grading and screening the tunnel hole slag into large / medium / fine three-level aggregate, and then crushing and recombining to form graded improved aggregate; constructing a multi-layer backfill structure of a base layer, a transition layer and a reinforcing layer; interface shear strength is achieved through the gravel-geogrid composite transition layer; adopting a vibratory roller to implement a static pressure and vibratory rolling combined process with adaptive levels; a coarse / fine-particle-size two-stage cement stabilized macadam layer is laid on the top to form a permeation drainage channel, and a transverse drainage blind pipe system is arranged to achieve three-dimensional drainage. According to the technology, the problems that in traditional hole slag backfilling, aggregate grading discreteness is large, shear failure is likely to be caused by sudden change of interlayer modulus, interlayer combination weakening is caused by uneven layered rolling energy transfer, and structure instability is caused by pore water pressure accumulation are solved, and hole slag resource utilization and roadbed structure performance collaborative improvement are achieved.

The invention discloses a low-temperature connecting method for glass and a C / C composite material, and relates to a connecting method for the glass and the C / C composite material. The problems that the performance of a base material is reduced and interface bonding is poor due to the fact that the connection temperature of an existing C / C composite material and glass is too high are solved. According to the method, firstly, a metal modified layer is prepared on the surface of the C / C composite material through magnetron sputtering, a carbide reaction layer is generated at the interface of the composite material, then connection of the C / C composite material and microcrystalline glass is achieved at the temperature of 580-660 DEG C through Bi2O3-B2O3-ZnO glass brazing filler metal, a microstructure mainly comprising a glass phase is formed in a welding seam, and the welding seam is formed. A continuous reaction layer is generated at the interface of the glass brazing filler metal and a glass base material, the glass brazing filler metal and the C / C composite material are connected through direct combination of oxides on the surface of a metal modified layer, and formed welding seams are compact and free of defects such as air holes and cracks. And the shear strength of the obtained joint can reach 13MPa.

The invention discloses a method for calculating the shear strength of a weak structural plane based on a Barton formula, and relates to the field of shear strength calculation, and the method comprises the following steps: introducing a reduction coefficient into a traditional Barton formula, and constructing an improved Barton formula; the shear strength of the weak structural plane is calculated through an improved Barton formula; the improved calculation model is regressed into an original Barton formula when no filler exists, theoretical continuity is guaranteed, compatibility with a traditional model is achieved, meanwhile, the defects of the traditional model are well overcome, and an important theoretical basis is provided for prediction of the shear strength of the weak structural plane. An improved Barton formula is utilized, the weakening effect of the soft filler on the rock mass structural surface can be reflected, the relation between the thickness of the soft filler and rock wall roughness attenuation can be accurately quantified, and compatibility with a traditional model is achieved; and the applicability, reliability and precision of prediction of the shear strength of the weak structural plane are effectively improved.

The present invention relates to the technical field of adhesive strength testing, and discloses an adhesive bonding strength testing device and method, comprising a test bench, wherein a support rod is fixedly connected to a side surface of the test bench, a support arm is fixedly connected to a top surface of the test bench, a hydraulic rod is fixedly connected to a rear side surface of the support arm, a strength testing mechanism is arranged at the top end of the hydraulic rod, a pressure rotating shaft is arranged at the top surface of the strength testing mechanism, a pressure sensor is arranged at the top end of the pressure rotating shaft, a mounting plate is arranged at the top side of the pressure sensor, the strength testing mechanism comprises a pressure groove rod, a pressure sliding rod, an upper lifting plate, a guide sliding rod, and a lower fixing plate, the pressure groove rod is fixedly connected to the top end of the hydraulic rod, and the present invention measures the shear force applied by two bonding components at a specific rate by stretching the coating disc surface, and the shear strength of the bonding can be determined by measuring the maximum shear force applied before the bonding fails.

To provide an opening reinforcement method capable of strengthening the shear strength, bending strength, and axial strength of a steel beam having openings.SOLUTION: A square frame 21 having a rectangular frame shape is welded on the periphery of the open hole 15 on a first surface 12a of a web 12 of a steel beam 10. Further, on the periphery of the open hole 15 on a second surface 12b, which is the reverse surface of the first surface 12a, a square frame 22 having the same shape as the square frame 21 but rotated 45 degrees relative to the square frame 21 is welded. With this configuration, the area around an open hole 15 formed in a web 12 of a steel beam 10 is reinforced.SELECTED DRAWING: Figure 2

The invention relates to the technical field of slope reinforcement, and provides a micro pile combination reinforcement method for a highway expansive soil slope, which comprises the following steps: when the current stability safety coefficient, the current uplift bearing capacity, the current shear strength and the current flexural bearing capacity all meet the corresponding preset conditions, taking the current design size parameter as the final design size parameter; and according to the final design size parameters, the grouting amount of each hole in a first pile of the steel pipe pile assembly and the grouting amount of each hole in a second pile of the cast-in-place pile assembly are determined, and the steel pipe pile assembly is constructed on the slope bottom face of the expansive soil slope according to the grouting amount of each hole in the first pile. And then a cast-in-place pile assembly is constructed on the slope face of the expansive soil slope according to the grouting amount of each hole in the second pile. According to the method, the influence of the expansive soil property on design and construction of the micro piles is fully considered, interaction and combined arrangement of the micro cast-in-place piles and the micro grouting steel pipe piles are integrated, the safety and reliability of slope reinforcement are guaranteed, material waste caused by excessive conservative is avoided, and operability is high.

The invention relates to the technical field of stainless steel composite plates, in particular to a stainless steel composite plate for a thick bridge and a preparation method of the stainless steel composite plate for the thick bridge, and the method comprises the following steps: carrying out single assembly treatment to obtain a composite blank, carrying out primary heating and rolling on the composite blank, carrying out secondary heating, controlled rolling and controlled cooling treatment to obtain the composite plate, tempering and straightening; wherein the single-time assembly treatment specifically comprises the steps that beveling and drilling are conducted on the four edges of the to-be-compounded side of the base material to form air exhaust holes, the to-be-compounded face of the clad stainless steel is attached to the base material, then welding sealing is conducted, and vacuumizing treatment is conducted. The problems that the stainless steel composite plate for the high-performance thick-specification bridge is difficult to produce through symmetric assembly rolling and rolling is difficult to achieve through a conventional single assembly are solved, the produced stainless steel composite plate for the bridge is excellent in interface bonding, the shear strength is larger than or equal to 380 MPa, the yield ratio is smaller than or equal to 0.83, the impact Akv of a base material at the temperature of-40 DEG C is larger than or equal to 250 J, and the intergranular corrosion resistance of a covering material is excellent; and the steel plate has good comprehensive performance and plate shape.

The invention relates to the technical field of welding and connection, in particular to a method for improving the mechanical property of an aluminum alloy resistance spot welding joint, which comprises the following steps: preparing active adjuvant paste, placing the adjuvant paste in an extrusion device, coating at the corresponding position of a welding spot through automatic equipment such as a mechanical arm, adjusting corresponding spot welding parameters, and performing resistance spot welding. And forming a spot welding joint. In the resistance spot welding process, the active auxiliary agent added to the interlayer interface of the plate can remove an oxidation film on the surface layer of the aluminum alloy, adjust interface resistance and stabilize current distribution, so that the nugget size and form of a spot welding joint are improved, and splashing is reduced; and meanwhile, the active auxiliary agent reacts in the high-temperature molten aluminum to play roles in purifying melt and refining grains, so that the mechanical property of the aluminum alloy resistance spot welding joint is improved. Under the same test condition, the nugget size of the aluminum alloy resistance spot-welded joint added with the active auxiliary agent is increased by 10%, the grain size is reduced by 10-15%, and the tensile-shear strength of the joint is increased by 15-20%.

The utility model relates to a compression-shear test device for fractured rock mass, which comprises a detection assembly, the detection assembly comprises a detection table, a straight shear block is slidably connected to the upper side wall of the detection table, a driving rod is fixedly connected to the straight shear block, an abutting block is fixedly connected to the upper side wall of the detection table, and a rock sample located between the abutting block and the straight shear block is placed on the detection table. According to the device, when a rock sample is damaged, the magnetic plate can move along with the rock sample, the accuracy of the shear strength detection of the rock sample is improved, the device is different from a traditional rock sample downward pressing mode, a traditional pressure shaft does not move due to the fact that the traditional pressure shaft does not move, and the detection precision is improved. Meanwhile, through the arrangement of the transverse sliding assembly, the friction of transverse movement between the rock sample and the magnetic plate is avoided, and the accuracy of the shear strength detection of the rock sample is further improved.