41results about How to "Change stress distribution" patented technology

The invention relates to the field of methods for testing or analyzing concrete by virtue of the chemical or physical properties of a measuring material, particular to an evaluation method of the self-repairing effect of a self-repairing cement-based material. The evaluation method of the self-repairing effect of the self-repairing cement-based material is characterized in that the evaluation indexes comprise relative dynamic elasticity modulus, fracture behaviors (stress intensity factor recover rate and fracture toughness recover rate), constitutive behavior comparison, flexural rigidity recover rate and strength recover rate. The evaluation method comprises the following steps: step 1, preparing a test piece; step 2, prefabricating local cracks and dispersed cracks; step 3, testing all the parameters; step 4, completing self repairing; step 5, testing all the parameters; step 6, calculating, processing, and evaluating the repairing effect. The method is comprehensive in evaluation.

The invention discloses a reinforced stress shot blasting method. The method is characterized by comprising the following steps of: clamping a steel plate spring by using a fixture to ensure that the steel plate spring is directionally bent and a directional bending direction is opposite to a natural bending direction of the steel plate spring; and performing shot blasting treatment on the back surface of the directionally bent steel plate spring by using a shot blasting machine. The invention has the advantages that: certain prestress is applied onto the steel plate spring before the shot blasting treatment; the prestress and the impact force of a steel shot are coacted with each other to change the stress distribution of the steel plate spring; simultaneously, the position of the steel plate spring is relatively fixed and a stress elimination effect is more sufficient due to the clamping effect of the fixture.

The invention discloses an embedded type sensor of overall process shear stress of concrete dynamic damage, which comprises a granite protective cover, a d15 mode piezoelectric ceramic chip, an epoxy resin insulating layer, a shielding lead and a shielding joint, wherein the piezoelectric ceramic chip is welded with the shielding lead to form a whole and is wrapped by using high strength epoxy resin to form an insulating and waterproof protective layer; and the piezoelectric ceramic chip is bonded with the granite protective cover of which the external surface is roughened to form a whole by utilizing the epoxy resin, and thereby the sensor of the concrete internal dynamic shear stress is formed. The sensor has the advantages of interference exemption of a concrete internal stress field, overall process monitoring of concrete internal dynamic damage evolution, good interface compatibility, simple structure and low construction cost.

The invention discloses a connecting device and method for connecting column base joints and belongs to the technical field of building structure engineering. The connecting device for connecting thecolumn base joints comprises a first steel column, a first arc end plate, a second arc end plate, a second steel column, a sleeve and a connecting mechanism. A connecting hole is formed in the first steel column, and the first arc end plate is connected with the first steel column. The first side of the second arc end plate is connected with the first arc end plate though a fastening piece, and the second steel column is connected with the second side of the second arc end plate. The sleeve is arranged in the connecting hole, the first end of the connecting mechanism is movably connected withthe sleeve, and the second end of the connecting mechanism penetrates through the first arc end plate to be connected with the second arc end plate. According to the connecting device and method for connecting the column base joints, the column base joints are fabricated joints, joint ductility is good, plastic hinging is prevented from occurring to the column end, the mode is simple, the economical and practical effects are achieved, and on-site construction is convenient.

The invention relates to a stress control production process of a high-strength aluminum alloy pipe. The stress control production process comprises the steps that a, an extrusion mold is selected, the surface and size of the extrusion mold are checked before installing, and the roundness tolerance of the mold cannot exceed 0.10 mm; b, the extrusion mold is preheated, and the extrusion mold and an extrusion barrel are preheated to 400 DEG C-450 DEG C; c, an aluminum alloy hollow round ingot casting blank is preheated, an ingot casting is preheated to 400 DEG C-450 DEG C, and the temperature difference of the head and tail of the ingot casting is controlled to be smaller than or equal to 30 DEG C; d, the ingot casting blank is placed in the mold, extrusion is started, the extrusion speed is smaller than or equal to 1.0 mm/s, and the difference of a long shaft and a short shaft of the extruded pipe is smaller than 2.50 mm; e, roll pre-straightening is carried out on a straightening machine; f, offline quenching is carried out, the pipe is quenched through vertical quenching equipment, during charging, aluminum wires are bound at the upper and lower proper positions of the pipe to reduce longitudinal bending generated after quenching, and a penetrating rod is used for increasing the contact area and balancing the stress on the two sides of the wall thickness of the pipe; and g, stretcher straightening finishing is carried out, profiling stretch core cushions are arranged in the two ends of the pipe, an arc-shaped stretch jaw is used for carrying out tension stretching on the pipe, and the stretch rate is controlled to be 1.0%-3.0%.

The invention provides a method for preventing and controlling the rock burst of a stope roadway for an unequal-width entry protection coal pillar. The method comprises the following steps that beforethe stope roadway is tunneled, a pressure relief roadway is arranged on a top plate of the unequal-width entry protection coal pillar, then blasting and drilling are carried out in a coal seam on a base plate of the pressure relief roadway so as to manufacture a loose pressure relief area, when working face mining is propelled into a dangerous zone of the stope roadway, along the side facing thepressure relief roadway, pressure relief chambers are tunneled every 12-15 m, drilling and blasting are carried out in the chambers in the direction towards the pressure relief roadway, a fracture body is formed between every two chambers through blasting to dissipate the impact energy of the coal pillar, the effect of buffering and protecting the stope roadway is achieved, and the safety of the roadway during the whole service period is ensured.

The invention relates to a secondary anvil of an octahedral pressure cavity static high-pressure device. An anvil body is in a cube shape; an anvil surface is a regular triangular surface formed by cutting a corner of the cubic anvil body; at least one circle of outer ring surface is arranged around the anvil surface; the outer ring surface in each same circle comprises three trapezoidal slants which are same in shape and size; a regular triangle is enclosed by the bottom edges of the three trapezoidal slants. The secondary pressurizing unit of the octahedral pressure cavity static high-pressure device comprises the eight secondary anvils, a previous sealing strip and an octahedral pressure transmitting medium. Compared with the traditional secondary pressurizing unit, for the secondary pressurizing unit which comprises the secondary anvils disclosed by the invention, experiments indicate that the blasting probability is obviously reduced during operation and the maximal pressure which can be achieved a the body of an octahedral pressure cavity can be increased.

The invention discloses a method for preventing impact ground pressure of a hard roof remained roadway by a buffer pressure relief belt and a wide roadway flexible wall. The method is characterized bycomprising the steps that firstly, side expanding and bottom excavating are carried out on the coal wall side of an original remained roadway, and coal bodies after side expanding is carried out areloaded into a woven bag for stand-by application; in accordance with a conventional method, holes are punched in the coal wall after side expanding is carried out for blasting, and the buffer pressurerelief belt with the width of 8-12 m is artificially manufactured; the woven bag with loaded materials is used as the wall material, and an artificial wall with the width of 1.5-1.6 m is built alongthe space position after side expanding is carried out; and the flexible wall is reinforced and blocked by a combined technique of a protective net and a single prop. Through the buffer pressure relief, the impact properties of the coal bodies are changed; and the artificial flexible wall and blasting in the roadway side are adopted to form a flexible body so as to realize impact prevention of theremained roadway.

The invention discloses a bearing ring having opening grooves, and a bearing. The bearing ring has two end faces facing toward an axial direction and in opposite arrangement. Opening grooves penetrating into the bearing ring in the axial direction are arranged on at least one end face. The outer ring and/or inner ring of the related bearing are designed with the bearing rings having the opening grooves.

The invention discloses a heat treatment deformation control method for a 23Co14Ni12Cr3MoE steel large part. The heat treatment deformation control method comprises the steps of stress relief tempering, gas-cooled quenching, ice-cold treatment, low-temperature tempering, correction, final tempering and the like. According to the heat treatment deformation control method, vacuum gas-cooled quenching is adopted to replace oil-cooled quenching with a relatively high cooling speed, the hardness, tensile strength, yield strength, fracture toughness and the like of the part after heat treatment allmeet the technical standard requirements, moreover, the generation of quenching stress can be reduced, the part is basically not deformed after heat treatment, and the size precision meets the designrequirements.

The invention relates to the technical field of glass processing, in particular to a self-bursting resistant microcrystalline glass. The modified microcrystalline glass comprises the following raw materials: 15-20 parts of fluorite, 10-15 parts of dolomite, 10-13 parts of calcite, 30-35 parts of vanadium-titanium-iron ore, 5-8 parts of soda ash, 4-6 parts of silicon phosphate, 0.17-0.24 part of boron oxide, 0.05-0.12 part of tin oxide, 01-0.03 part of a lanthanide series trace additive. Specifically, the lanthanide series trace additive contains lanthanum, praseodymium and neodymium three elements. The preparation process of the glass includes compounding, melting, clarifying, forming, toughening treatment, homogenizing treatment and other steps. The glass treated by the process has very stable internal and external stress distribution, can maintain good strength, hardness and impact resistance, and also can reduce the self-bursting rate of glass.

The invention provides an unidirectional ceramic matrix composite thermal expansion coefficient prediction method considering damage evolution. In the process that the ceramic matrix composite is heated to deform, thermal stress is generated in components to cause damage, and the evolution of the damage further changes the stress distribution of the components, so the macroscopic deformation of the material is changed, and then the coefficient of thermal expansion is affected. Damage such as matrix cracking and interface slippage is considered, the interface forward and reverse slippage lengthcaused by temperature change is calculated, the influence of damage evolution on component stress distribution is considered during material macroscopic deformation calculation, the macroscopic thermal strain and the thermal expansion coefficient of the material are finally obtained through calculation, and the precision of a prediction result can be greatly improved.

The invention relates to a method for dismantling a current rain and sewage confluence square ditch, which is used for breaking an existing first rain water square ditch in a foundation trench, the first rain water square ditch is at least partially embedded in a rock-soil body below a main road, and the method at least comprises the following steps: respectively constructing a steel sheet pile support and a hanging net anchor-shotcrete support on one side of the foundation trench facing a first direction and a second direction; the foundation trench is excavated to the top of the first rainwater square ditch, and a hole is formed in a top cover plate of the first rainwater square ditch; the first rainwater square ditch is filled with a concrete mixture through the hole; and when filling of the concrete mixture is completed and the coagulation strength of the concrete mixture reaches a threshold value, chiseling is conducted from a top cover plate of the first rainwater square ditch, and excavation is continuously conducted to the bottom of the foundation trench.

The invention provides a bionic composite structure capable of simultaneously enhancing adhesive force and friction force, which is characterized by comprising a support layer, the column array comprises columns which are formed on the supporting layer, arranged in an array mode and provided with soft elasticity; and the micro-nano reinforcements are all embedded in the column body, and the micro-nano reinforcements are nanowires or nanotubes or nanosheets. According to the invention, through the synergistic effect of the support layer, the anisotropic cylinder array and the nano reinforcement, the material has excellent adhesion performance, friction performance and wear resistance on a rough surface; furthermore, the porous support layer can effectively reduce the modulus of the supportlayer, is beneficial to deformation and bending, realizes better contact on a rough surface, and can absorb more energy in the debonding process, thereby being beneficial to realizing strong adhesion.

The invention discloses a side pushing device for bending forming of an electromagnetic type pipe fitting. The side pushing device is characterized in that the bottom surface of a side pushing block is an inward-concave arc-shaped column surface, the bottom surface of the side pushing block is in contact with the pipe fitting, a plurality of strip-shaped through grooves which are arranged at intervals in the circumferential direction are formed in the inward-concave arc-shaped column surface, and a rubber sheet is attached to a notch of each strip-shaped through groove; a plurality of electromagnetic pressing block units which are arranged in parallel at intervals in the circumferential direction of the inward-concave arc-shaped column surface are arranged inside the side pushing block, and each electromagnetic pressing block unit is arranged in parallel to the strip-shaped through grooves and is installed inside the side pushing block; and each electromagnetic pressing block unit is mainly composed of a plurality of electromagnets which are connected in series through pressing blocks to form a row, and the two ends of the series-connected electromagnets are connected with magneticbodies through the pressing blocks, and coils are wound around the electromagnets. According to the side pushing device, the stress distribution of a bending section in the bending forming process ofthe pipe fitting can be changed, so that the cross section distortion of the pipe fitting can be relieved, the thinning degree of the thickness of the outer side wall of the pipe fitting is reduced,the controllability is high, and the flexibility is high.

The invention provides a cantilever beam electric field detection device. The cantilever beam electric field detection device comprises a vibration source, a cantilever beam, a piezoelectric materialblock, a cavity and an organic conjugated polymer material, the cantilever beam is fixed on the vibration source, the piezoelectric material block is arranged on the top surface of the cantilever beamand close to the fixed end, the piezoelectric material block is connected with an external circuit, the cavity is arranged in the cantilever beam, and the cavity is filled with the organic conjugatedpolymer material. The device has the advantage of high electric field measurement sensitivity.

The invention belongs to the field of desulphurization apparatus in metallurgy casting industries, and especially relates to a molten iron desulphurization stirring spray gun. The stirring spray gun comprises a flange connecting piece (1), a stirring shaft (2) fixedly connected to the flange connecting piece (1), a stirring blade (3) fixedly connected to the lower part of the stirring shaft (2), a refractory material layer (7) attached to the stirring shaft (2) and the stirring blade (3), and a spray pipe (4) fixedly sleeved in the stirring shaft (2). Semicircular-cylinder-shaped vaporization chambers (5) are arranged on a side wall of the stirring blade (3), wherein the semicircular-cylinder-shaped vaporization chambers (5) are arranged with equal shares. Spray ports (6) are arranged on the semicircular-cylinder-shaped vaporization chambers (5). The inner cavity of the spray pipe (4) communicates with the spray ports (6). The number of the semicircular-cylinder-shaped vaporization chambers (5) is three. The stirring blade (3) is in a shape of a round disc. An annular stress adjusting rib (8) is arranged in the refractory material layer (7). The molten iron desulphurization stirring spray gun provided by the invention is advantaged in simple structure, long service life, low cost, and high desulphurization efficiency.

The invention discloses a high-sealing low-friction one-way bearing. The defect that the existing sealing performance and rotating speed cannot be balanced is overcome. The high-sealing low-friction one-way bearing comprises a bearing outer sleeve and a bearing inner sleeve, a limiting groove is formed in the inner edge, close to the end face, of the bearing outer sleeve, a corresponding sealing groove is formed in the position, corresponding to the limiting groove, of the bearing inner sleeve, a sealing ring is arranged between the bearing outer sleeve and the bearing inner sleeve, and the sealing ring comprises a limiting piece and a bent piece which are elastically connected. The tail end of the limiting piece is fixedly connected to the limiting groove, the bent piece is provided withan abutting folded corner, the abutting folded corner abuts against the interior of the sealing groove, the tail end of the bent piece points to the limiting piece, the bent piece and the limiting piece form a lubricating notch, and the lubricating notch is formed in the side away from the end face of the bearing. According to the bearing, the sealing ring is slightly separated from the bearing inner sleeve through the sealing ring in a high-speed rotating state, so that the friction force is reduced, and the bearing can adapt to the working condition of high-speed rotation.