2489 results about "Shear resistance" patented technology

The invention discloses a temperature resistant salt tolerant high efficiency gel and a preparation method and application thereof. The preparation method is characterized in that the preparation method comprises the following steps: preparing a comb-shaped associated copolymer PAH containing macromonomers and functional hydrophobic monomers into an aqueous solution having the concentration of 0.1 to 4g / L, the crosslinking agent concentration of 0.01 to 1.0g / L, the surfactant concentration of 0.01 to 8mmol / L and the sodium sulfite thermal stabilizer concentration of 0.005 to 1.0g / L; adding the aqueous solution into a mixing container with a stirring device; stirring the aqueous solution evenly at the room temperature; regulating the pH value of the solution to be equal to between 4 and 11, and obtaining a temperature resistant salt tolerant high efficiency gel polymer solution system used for tertiary oil recovery and scavenge, displacement modification, profile modification or water shutoff. The polymer solution system has micro-crosslinking to form the gel during the flowage inside the oil reservoir. The gel has good elasticity, not easy dehydration, stable gelling performance, and excellent tackification, temperature resistance, salt tolerance, shearing resistance and ageing resistance.

The invention relates to an amphoteric hydrophobically-associating polymer and a preparation method thereof, and is mainly used for solving the problem that polymers are poor in heat resistance, salt tolerance and shear resistance, and incapable of meeting the requirements of tertiary oil recovery in the prior art. According to the amphoteric hydrophobically-associating polymer and the preparation method thereof disclosed by the invention, the problem is solved well by adopting the technical scheme that the amphoteric hydrophobically-associating polymer contains, in parts by weight, 5-99.9 parts of non-ionic water-soluble monomer, 0-50 parts of anionic monomer or / and cationic monomer, and 0.1-10 parts of hydrophobic monomer with surface activity. The amphoteric hydrophobically-associating polymer and the preparation method thereof can be used for industrial production and application of polymers for oil field tertiary oil recovery.

The invention discloses a device and a method for testing shear performance of an asphalt mixture. The shear strength and shear fatigue life of the asphalt mixture under different temperature conditions are tested by adopting a circular ring shearing test. The method comprises that: before the test, an asphalt mixture test-piece is subjected to heat preservation in a temperature control box at a preset test temperature for over 6 hours; in the test, the asphalt mixture test-piece is arranged on a circular ring, and is loaded through a pressure head to cause shear failure so as to form a conical shear failure surface, and the shear strength of the asphalt mixture is calculated; and according to requirements, a specific load in a range of 0.1 to 0.9 time of failure load is selected to perform a repeated loading fatigue test on parallel test-pieces, the loading waveform is sine waves, the frequency is 10Hz, and the shear fatigue life of the asphalt mixture at different stress ratios is read out. The test method has important significance for studying the shear performance of the asphalt mixture and designing and evaluating the material of the asphalt mixture.

The invention discloses acrylamide modified polymer micro-crosslinking gel and a preparation method thereof. The preparation method is characterized in that the method comprises the following steps that: acrylamide modified polymer PAE containing functional macro monomer is prepared into an aqueous solution with the concentration between 0.1 and 4g / L, the concentration of crosslinking agent between 0.01 and 1.0g / L, the concentration of surface active agent between 0.01 and 8mmol / L and the concentration of heat stabilizer sodium sulfite between 0.005 and 1.0g / L; the aqueous solution is added in a mixing container with a stirring device and is stirred evenly at room temperature; the pH value of the solution is adjusted between 4 and 11 to prepare a polymer solution system of the acrylamide modified polymer micro-crosslinking gel used for tertiary oil recovery and displacement, oil displacement modification, profile modification or water plugging; and the polymer solution system undergoes micro crosslinking during flowing inside an oil layer to form the gel. The acrylamide modified polymer micro-crosslinking gel has ideal elasticity, difficult dehydration, stable performance and excellent performances on tackifying, temperature resistance, salt resistance, shearing resistance and ageing resistance.

A structural building system including an improved, structural-load-bearing, building component, such as a building panel, having front and back sections, an insulating core, integral symmetrical joinery, a thermal break, and at least one shear resistance connector The panel is asymmetrical about one axis, and is designed to be directionally positioned with respect to the maximum anticipated force. A shear resistance connector array may be positioned between the front and back sections or may be integral to the front or back section. A face sheet may span one or more than one building panel, and provides structural support to the building system.

Golf equipment having improved cut and shear resistance that includes a polyurea composition, preferably saturated and / or water resistant, formed of a polyurea prepolymer and a curing agent, wherein the polyurea prepolymer includes an isocyanate and an amine-terminated compound, and wherein the curing agent includes a hydroxy-terminated curing agent, amine-terminated curing agent, or a mixture thereof.

The invention discloses a water soluble copolymer with high viscosity and salt resistance, and a preparation method and an application thereof. The preparation method comprises the steps of: adding acrylamide 20 weight parts, an anionic monomer or / and a cationic monomer 0.1-15 weight parts,, a vinyl polycyclic aromatic hydrocarbon 0.05-4 weight parts,, a surfactant 0.5-90 weight parts,, and deionized water 70-900 weight parts, into a three-neck reaction bottle, adjusting the solution pH to 2.5-9, introducing N2 for 30min, adding an initiator persulfate 0.001-0.2 weight parts, at 20-70DEG C, and reacting for 6-36 hours to obtain a low-molecular weight water soluble copolymer with molecular association ability, high viscosity and salt resistance, which can be used in intermediate-permeability oil reservoir and low-permeability oil reservoir development. An associated water soluble polymer oil displacement agent is obtained by preparing the copolymer into an aqueous solution with copolymer concentration of 0.3-3 g / L and surfactant concentration of 0.01-4 mmol / L, adding into a mixer with a stirring device, and stirring uniformly at room temperature; and the obtained oil displacement agent has high viscosity, salt resistance, temperature resistance and shear resistance, and can be used in intermediate-permeability oil reservoir and the low-permeability oil reservoir development.

The invention relates to a hard rock tunnel non-blasting digging blocking method and a construction method. According to the method, a hole drilling core taking technology is utilized, mutually engaged cutting peripheral holes are formed along a tunnel digging contour line, so that a hole wall-shaped digging free face is formed on the periphery of a tunnel face; a hydraulic splitting machine splitting technology is used, in addition, the characteristic that the tensile intensity and the shearing-resistant intensity of rock are much smaller than the pressure-resistant intensity is utilized, the tunnel face digging blocking is firstly carried out, in each digging block, the synchronous splitting digging splitting surfaces do not exceed two, in addition, the two splitting surfaces are in large-angle obtuse angle intersection, in addition, at least one digging free face vertical to the tunnel face is included, then, the digging construction sequence from the lower side to the upper side and from the periphery to the middle is adopted, and the smaller splitting force is used for carrying out rock pulling cracking and shearing cutting splitting digging on the tunnel face along the splitting surface. The hard rock tunnel non-blasting digging blocking method has the advantages that the adverse influence of vibration, noise and dust in the hard rock digging construction can be eliminated, and the utilization rate of tunnel hole slag as building stone materials can be improved.

A steering column assembly includes a first jacket defining a first bore and a second jacket defining a second bore aligned with the first bore prior to collapse of the first jacket and the second jacket. A jacket connector extends through the bores to interconnect the first jacket and the second jacket. The jacket connector includes a pre-determined shear resistance, above which the jacket connector is sheared to permit telescopic movement between the first jacket and the second jacket. Accordingly, in response to an axial load greater than the pre-determined shear resistance of the jacket connector being applied to one of the first jacket and the second jacket, the jacket connector shears, permitting the telescopic movement. The jacket connector includes a pin defining a pin bore. The pin bore defines a cross sectional area, with the pre-determined shear resistance depending upon the cross sectional area of the pin bore.

The invention provides a hydrophobic associated polymer, comprising repeating units shown in formula (I) and formula (II), wherein x: y = 1: (0.001 to 0.06); A is a monomeric unit of a hydrophobic monomer; the viscosity average molecular weight of the hydrophobic associated polymer is 5 to 35 million. Compared with the prior art, the hydrophobic associated polymer comprises two monomeric units, and a hydrophilic unit is a monomeric unit of acrylamide, can provide a hydrophilic group for a hydrophobic associated polymer, and ensures that the polymer has good water solubility; a hydrophobic unit is a monomeric unit of the hydrophobic monomer, can provide a hydrophobic side group for the hydrophobic associated polymer, and ensures that a polymer chain has a certain hydrophobic character, and hydrophobic groups gather in water due to a hydrophobic interaction to form a spatial network structure, thereby providing necessary viscoelasticity for a solution; under the combined action of the two units, the temperature resistance and salt tolerance and shear resistance of the hydrophobic associated polymer are improved.

The invention relates to a method for preparing a fluorine-containing modified amphoteric water-soluble polymer, in particular to a method for preparing the fluorine-containing modified amphoteric water-soluble polymer by a cosolvent method and belongs to the technical field of water-soluble macromolecular synthesis. Methacryloyl ethyl-N and N-dimethyl propanesulfonic acid (DMAPS) as amphoteric monomers and perfluoro hexyl ethyl acrylate (PFHEA) and acrylamide (AM) as hydrophobic monomers are copolymerized in a single solvent; azobisisobutyronitrile (AIBN) is used as a catalyst; and the fluorine-containing modified amphoteric water-soluble polymer is obtained. The polymer has good water solubility and remarkable interface activity, thickening, shearing resistance, temperature resistance and salt resistance. Through a mixed solution of anhydrous acetone and anhydrous ether, the polymer is precipitated, dried and pulverized to obtain a powdery product; and the powdery product has wide application prospect in the development of an oil field, dope, printing, household chemical, medicament and other fields.

The invention relates to an inverse emulsion polymer thickener for a fracturing fluid and a preparation method thereof. The thickener is polymerized by water, 2-acrylamidyl-2-methyl sodium proparesulfonic acid liquid with mass fraction of 50%, alkyl acrylamide, acrylamide, a cationic monomer, N, N-methylene bisacrylamide, a tween-80 emulsifier, ethylene diamine tetraacetic acid disodium salt, 30% sodium hydroxide, white oil, acrylic ester, a span-80 emulsifier, sulfite, a peroxysulphate initiator, a water-soluble azo initiator and OP-15. According to the invention, raw materials are industrial products, and purification is not needed before reaction; polymerization is initiated by initiators by adding a complexing agent, and the preparation process is simple; the thickener provided by the invention is fast in dispersing, easy to prepare, free from pollution and harm, small in use level and good in stability, in particular resists high temperature of 220 DEG C, and is suitable for fracturing a high-temperature stratum; and the thickener is higher in shear resistance, can meet the fracturing construction of high flow, has high sand carrying performance, and is free from residue and is not harmful to the reservoir.

The invention relates to a pavement structure and a testing device for bridge deck pavement bonding interface shearing-resistance characteristic, which are based on mechanics principle and indoor test, effectively simulate road surface and simulate stress conditions, can realize continuous change with 0-80 degrees of shearing angle, meet needs of different working conditions and are suitable for the design and research of the pavement structure, the indoor test and engineering test. The testing device comprises an upper part and a lower part, each part comprises a bearing board, a rolling shaft, an arc base, a semi-circular clamp, an internal collet and a clamp fixing device. The whole device also comprises an angle dial scale and an angle pointer and other attached parts which are used for indicating the size of the angle. A square testing piece is arranged in the internal collet, the semi-circular clamp and the base can rotate relatively, after the shearing angle is set, the clamp and the base are fixed by the clamp fixing device. The horizontal surface of the other side of the base is contacted with the bearing board in a rolling way by the rolling shaft, so as to lead the device loading to generate vertical displacement and to move horizontally at the same time.

The invention discloses a compound type connection shear wall structure and an assembling method thereof. The compound type connection shear wall structure comprises N shear wall components of the same structure, wherein every two adjacent shear wall components are connected through a compound shear key and a key groove so that a compound type connection shear wall can be formed. Due to the mutual guide-in effect of the compound shear keys and the key grooves, the construction precision is improved, and eccentric compression generated by inaccurate assembling is avoided. Because the shear key on each shear wall component below can bear the weight of the corresponding shear wall component above when the next layer is assembled, assembling of a wall body of a previous layer can be instantly conducted after floor pouring is completed without waiting till floor concrete reaches the strength, and the assembling cycle of floors can be greatly shortened. The shear keys of the shear wall components below are embedded in the key grooves of the shear wall components above, the shear keys can bear transverse shearing force, the shear resistance of the structure is enhanced, and reliability of the structure is enhanced.

The invention relates to an anti-explosion impact polyurea coating and a preparation method thereof, and belongs to the field of coating compositions. The anti-explosion impact polyurea coating comprises two components A and B, wherein the component A is a semi-prepolymer component obtained by reacting 40 to 60 parts of isocyanate, 40 to 60 parts of polyester polyol and 1 to 10 parts of graphene paste; the component B comprises 10 to 30 parts of a chain extender, 15 to 30 parts of polyether polyol, 40 to 60 parts of amino-terminated polyether, 1 to 10 parts of graphene paste, a pigment and a trace amount of an auxiliary. The polyurea coating has the performance of strong physical strength, high shear resistance, high strength retention under high-speed impact and high-speed large deformation, high low-temperature flexibility and the like, and is applicable to an anti-explosion place.

The invention discloses a polyamide and amine hybridized nanosilicon dioxide hyperbranched polymer and a preparation method thereof. The preparation method of the polymer comprises the following steps of firstly, modifying the surface of nanosilicon dioxide by using a coupling agent; then, carrying out Michael addition reaction and amidation reaction on the modified nanosilicon dioxide by using ethylenediamine and methyl acrylate; finally, carrying out functional modification by using allyl glycidyl ether to obtain a functional polyamide and amine hybridized nanosilicon dioxide monomer, and initiating polymerization reaction on the functional polyamide and amine hybridized nanosilicon dioxide monomer, acrylamide, acrylic acid and a heat-resistant and salt-tolerant monomer by using a redox initiator or azobis(isobutylamidine) initiator. The hyperbranched polymer has a network structure with a polyamide and amine hybridized nanosilicon dioxide unit as a center, has excellent shear resistance, strong thickening property, heat resistance and salt tolerance, and is wide in adaptability and capable of being used as an oil displacement agent for increasing the recovery rate of raw oil in an oil field environment with a high mineralization degree and a wide temperature range; the preparation method of the polyamide and amine hybridized nanosilicon dioxide hyperbranched polymer is reliable in principle, simple and convenient to operate and wide in application prospect.

The invention discloses a high-temperature brazing filler metal, relating to a brazing filler metal. The invention solves the problem that joints obtained by using the prior brazing filler composite material have low shearing strength. The brazing filler metal comprises Ti or TiH2, Ni and Nb. When the high-temperature brazing filler material is used to braze C / SiC composite material and the brazing joint of the C / SiC composite material, room temperature three-point bending strength reaches 50MPa-71MPa, and the room temperature shearing strength of the brazing joint of the C / SiC composite material and metal reaches 90MPa-180MPa, moreover, the retention rate of the 800 DEG C high-temperature shearing strength of the brazing joint is more than 69% and the retention rate of the 800 DEG C high-temperature shearing strength is more than 42%. When the high-temperature brazing filler material is used to braze black lead and the joint of Nb, the room temperature shearing strength reaches 30MPa-60MPa.

The invention relates to a special-shaped three-dimensional knitted fabric and a manufacturing method thereof, which relate to the knitted fabric. The special-shaped three-dimensional knitted fabric with at least one of an upper surface and a lower surface being a concave-convex special-shaped curved face, and favorable air permeability, support performance and shearing resistance, and the manufacturing method thereof are provided. The special-shaped three-dimensional knitted fabric comprises an upper fabric layer, a middle fabric layer and a lower fabric layer, wherein the upper fabric layer or / and the lower fabric layer is / are provide with a concave-convex curved face(s) in a knitted longitudinal direction(s); and the middle fabric layer is formed by connecting yarns with flexural rigidity. According to a fabric structure and a texture requirement, required materials of the upper fabric layer, the required lower fabric layer and the middle fabric layer are selected; according to structural features of the fabric, the yarns are sewed on a guide bar; according to special-shaped structural features of the fabric, warp run-in of the fabric is set, and a distance between two needle beds can be adjusted in real time when the fabric is knitted in different horizontal lines according to variation in thicknesses of the different horizontal lines of the fabric; and a drawing device draws the knitted textile from the needle beds when knitting is carried out simultaneously.

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.

Emulsions of mobility control polymers can be used to increase recovery of crude oil from a subterranean hydrocarbon-containing formation. A flooding fluid comprising the polymer emulsions are injected into a well that is in contact with the subterranean hydrocarbon-containing formation. The polymers can be temporarily cross-linked and have protected shear degradation and improved injectivity into the well; the shear resistance can be measured in terms of viscosity loss due to shear, and the improved injectivity can be measured in terms of the flooding fluid's filter ratio, flow rate, and viscosity.

The invention discloses a straight cut testing system for rock and earth mechanics, relating to a cutting system. The invention is composed of outer frame, horizontal loading system, vertical loading system, cut box, and measuring system; the horizontal loading system, the vertical loading system, the cut box and the cut box are fixed on the outer frame, respectively; the horizontal loading system, the vertical loading system and the measuring system are connected with the cut box, respectively. The invention has high measuring accuracy and good stability; all the data are automatically collected, thus reducing artificial reading error; it adopts variable frequency electric motor so as to reduce the manufacturing cost on the premise of assuring a stable cutting speed; all the parts are removable, convenient to transport and install. It can be used in determining peak values and remaining shearing strength of fine earth, coarse earth and soft rock and provide strength parameter for engineering design and rock and earth stability.

The invention belongs to the technical field of development of oil fields, and particularly relates to a seawater-based fracturing fluid which is suitable for preparing sweater and can be used for realizing continuous blending and a preparation method thereof. The seawater-based fracturing fluid is prepared from the following raw materials in part by weight: 0.5-1.5 parts of thickening agent, 0.3-1.0 parts of crosslinking agent, 0.2-0.6 parts of surfactant, 0.01-0.2 parts of pH value regulating agent, 0.01-0.2 parts of viscosity breaker, 46.5-64 parts of seawater and 35-50 parts of desalted seawater. The seawater-based fracturing fluid has the advantages of suitability for preparing seawater, capability of realizing continuous blending, high temperature resistance, high salt resistance, high shear resistance and quick dissolvability.

The invention relates to a preparation method of a defoaming agent for a waterborne system. The preparation method of the defoaming agent for the waterborne system comprises the following steps: a) adding silicon oil, gaseous silicon dioxide and catalyst into a reaction container according to proportions, and preparing silicon cream under an agitating condition protected by nitrogen; b) adding hydrogen-containing silicon oil and allyl polyether into the reaction container, agitating under the protection of nitrogen, increasing temperature and adding an initiator for reaction to obtain polyether modified organic silicon; c) jading the silicon cream obtained in step a), the polyether modified organic silicon obtained in step b) and an emulsifier into the reaction container, adding water for emulsification under a high-speed agitating condition, and adding a thickening agent to regulate viscosity to obtain a product. The defoaming agent prepared by adopting the preparation method provided by the invention has the advantages that the active components are low, the manufacturing cost is low and the environmental friendliness is better; the emulsification is stable, the compatibility in the waterborne system is good, the defoaming agent is easy to disperse, the surface tension is low, the defoaming speed is quick, the foam inhibiting time is long, the thermal resistance, shear resistance and acid and alkali resistance thereof are good, and the defoaming agent can adapt to various places; the defoaming agent can be separately used and can also be jointly used with other adjuvants, the stability is good, the phenomenon of oil floating due to demulsification does not occur, no sediment is produced and shrinkage cavities during coating are not caused; and the defoaming agent is also very effective to non-waterborne systems.

The invention discloses a testing device for observing shear deformation failure characteristics between a tubular pile and a grouting soil body. The testing device comprises a fixing platform, a tubular pile model testing box, a loading mechanism and a monitoring system, wherein the fixing platform comprises a base plate, a top plate and a plurality of connecting screw rods; the tubular pile model testing box comprises a bottom wall, two side walls, a rear wall and a front wall, wherein the front wall is movably arranged between the side walls, and is made of colorless transparent organic glass; the monitoring system comprises a displacement sensor, a pressure sensor and a strain rosette group arranged on the outer surface of the tubular pile; the strain rosette group comprises a plurality of strain rosettes which are uniformly distributed along the central axis direction of the tubular pile, and are connected with an automatic recorder. According to the invention, a semi-circular pipe pile is adopted, so that the shear deformation failure characteristics between the tubular pile and the grouting soil body can be observed conveniently, and the shear resistant intensity between the tubular pile and the grouting soil body can be observed; a camera device is adopted for recording the video of the testing process; the visual testing enables the analysis to be relatively intuitive.

The invention relates to the technical field of structural systems of shear walls, and discloses a reinforced type prefabricated steel bar concrete shear wall, a structural system and a construction method thereof. The reinforced type prefabricated steel bar concrete shear wall is composed of a prefabricated wallboard connected from up to down, and comprises reinforced vertical steel bones, steel bars and poured concrete wall bodies, wherein the reinforced vertical steel bricks and steel bars are located in the edge area of the prefabricated wallboards. The vertical steel bones are arranged discontinuously and are arranged at the connection nodes of the upper and lower ends of the prefabricated wallboards; edge longitudinal bars are fixed by horizontal hooped reinforcements or tie bars and arranged outside the reinforced vertical steel bones in a sleeved mode. The outer sides of the reinforced vertical steel bones are connected with the edge longitudinal bars in a lapped, anchored or welded mode, one end extends out of the concrete walls; the height of the concrete walls is not higher than the height of the edge longitudinal reinforcements and wall body vertical steel bars; the upper and lower adjacent prefabricated wallboards are connected by the corresponding reinforced vertical reinforcements, edge longitudinal reinforcements and walls body vertical steel bars, and connecting gaps are poured at the connection nodes. The reinforced type prefabricated steel bar concrete shear wall, the structural system and the construction method thereof have the advantages of being low in cost and convenient in construction; having excellent shear strength at the connections; being convenient to control the construction quality.

The invention relates to an oil-gas well fracturing fluid used in a high-temperature stratum at 180 to 200 DEG C in an ultrahigh temperature compression fracture stimulation technique. The technical proposal comprises: the raw materials used by the fracturing fluid comprise the following components in percentage by weight: 0.3 to 0.6 percent of thickening agent, 0.1 to 0.7 percent of crosslinking agent, 0.3 to 0.6 percent of clay stabilizer, 0.2 to 0.6 percent of bactericidal agent, 0.1 to 0.4 percent of pH conditioning agent, 0.3 to 0.6 percent of temperature stabilizing agent, 0.2 to 0.7 percent of cleanup additive, 200 to 1500 ppm of gel breaker, 2 percent of potassium chloride, and 94 to 96 percent of water. The high-temperature fracturing fluid adopts high-temperature resistant hydroxypropyl carboxymethyl guargum as the thickening agent and uses a high-temperature crosslinking agent compounded from organic boron and organic zirconium. The fracturing fluid has the advantages of good shear resistance and temperature resistance, good gel breaking effect, friction resistance reduction and low permeability, wherein the viscosity can be kept between 70 and 80 MPa.s after the fracturing fluid is sheared for 120 minutes under the condition of 190 DEG C and 170s. The fracturing fluid is successfully applied to the Zhuanggu No.63 well of which the stratum temperature is 184.6 DEG C in Shengli Oil Field.

The invention relates to a high-temperature-resistant gelled fracturing fluid, and a preparation method and application thereof. The fracturing fluid is mainly prepared from the following components in percentage by mass: 0.4-0.8% of anionic polymer, 0.05-0.20% of crosslinking agent, 0.02-0.16% of pH regulator, 0.01-0.10% of delayed crosslinker, 0.1-0.8% of cleanup additive, 0.01-0.09% of viscosity breaker and the balance of water. The anionic polymer is a terpolymer and is copolymerized from the following components in percentage by weight: 60-70% of acrylamide monomer, 15-25% of anionic monomer, 5-15% of cationic monome, totaling 100%. The fracturing fluid can resist the high temperature of 210 DEG C above, has the advantages of crosslinkability, capability of carrying sand, shear resistance, salt resistance, no residue and the like, and is used for fracturing yield increase of hypotonic high-temperature ultra-deep wells.

The invention discloses a connection structure of a prefabricated bridge pier and a bearing platform, which is characterized in that the bridge pier is positioned by a positioning pier and is connected together with the bearing platform through a mounting island, and interactive shear keys are arranged between the bottom connection section of a pier body and the mounting island. The connection structure disclosed by the invention has the technical characteristics and effects that the lower part of the prefabricated bridge pier with an annular section is sleeved on the positioning pier so as to be convenient for positioning the pier body; the prefabricated bridge pier in the range of the cup-mouth mounting island is subjected to rough chiseling except the range of an externally-wrapped steel plate at a pier bottom, thereby ensuring the connection quality and effectively improving the stress performance of a bridge pier column; and the bearing platform is connected with the bridge pier through the annular mounting island, and the shear keys are arranged at the joint, thereby enhancing the shear resistance of the joint and facilitating construction. By adopting the connection structure disclosed by the invention, the bridge pier and the bearing platform are reliable in connection and stress, convenient in construction, simple in operation and easy to control, the workload of field welding and concrete pouring can be effectively reduced, and the construction progress can be accelerated.

The invention belongs to the field of civil engineering technology, and particularly relates to a bolted steel filling plate-sleeve connection node for a beam-post wood structure. The connection node comprises a wood beam, a wood post, a steel filling plate, a sleeve, a bolt, a gasket and a nut. The the beam-post connection node is formed by inserting steel filling plates in grooves of the wood beam and the wood post, the sleeve is embedded in the bolt hole on the beam-post connection node; after the bolt passes through the sleeve, the sleeve is pressed by the gasket through a stretch-draw bolt, so that the sleeve pushes against the steel filling plates to generate larger pressure, friction generated by pressure is utilized for shear resistance and the increasing and decreasing of pressure stress is utilized for bending resistance. The connection node is definite in force transfer and convenient for construction, and gaps at the nodes almost have no influence on the load-carrying property and rigidity of the structure; in addition, the introduction of the sleeve can also prevent the local bearing damage of the wood below the gasket and reduce the contact pressure stress at the bolt of the wood beam (post), thus being beneficial to the exertion of strength of the wood. Compared with the existing connection mode, the connection node of the beam-post wood frame has large and stable bending-resistant rigidity.

The invention relates to a shear strength measurement method, in particular to a method for measuring the shear strength of a discontinuous shear plane of a rock by utilizing three-shaft compression. The method comprises the following steps of: S100, preparing a rock sample required by a three-shaft compression test; S200, carrying out the three-shaft compression test on the rock sample, wherein an axial load is applied after confining pressure application till the rock sample is sheared and damaged and generates residual deformation; S300, measuring an angle between the shear plane and the horizontal direction; S400, setting a plurality of grades of confining pressures and carrying out the three-shaft compression test grade by grade; and S500, calculating positive stress and shear stress according to the test data and a rupture angle of the rock sample and fitting relation curves of the positive stress and the shear stress by utilizing a least square method to obtain the shear strength. The method has the beneficial effect that the residual deformation is utilized for replacing a cement pouring process to carry out shear test on the discontinuous shear plane of the rock sample, so that the shear strength of the discontinuous shear plane of the rock sample can be quickly and accurately obtained.