202 results about "Resilient modulus" patented technology

The invention discloses a tire finite element modeling and multidirectional rigidity optimization method and system based on characteristic lines. The method comprises the following steps: extracting tire section characteristic lines from a three-dimensional digital model; introducing the tire section characteristic line into a finite element analysis environment, generating a three-dimensional tire geometric model by rotationally scanning the characteristic line, and performing grid division on the model; setting tire material attributes, performing zoning setting on the model according to a tire crown, a tire shoulder and a tire side wall, and setting tire thickness based on zoning; applying a constraint boundary condition at the center of the tire, and establishing a contact form of the tread and the ground; a progressive inflation pressure load is applied, the deformation state of the inflated tire is calculated, and longitudinal rigidity, radial rigidity and lateral rigidity calculation and analysis steps are set; the tire elasticity modulus and the cord fabric thickness are used as design variables, and an optimization algorithm is adopted to solve a multi-objective optimization function. The method has the advantages of being simple in modeling method and high in practical operability, the tire modeling threshold can be lowered, and the fund and time cost of refined modeling is reduced.

The invention relates to the technical field of concrete preparation, in particular to sprayed concrete with high crack resistance and low rebound rate and a preparation method thereof. The nano aerogel, the polypropylene fiber and the modified vermiculite are creatively adopted to prepare the sprayed concrete, and the nano aerogel has the water retention and moisture absorption characteristics and plays an internal curing role in the concrete, so that the internal water loss rate is reduced, the shrinkage of the concrete is weakened, and the concrete is prevented from being damaged. Meanwhile, the polypropylene crude fiber with high breaking strength and elasticity modulus and a composite cross-linked network structure formed by the polypropylene crude fiber and the modified vermiculite can greatly improve the crack resistance and durability of the sprayed concrete under the interaction; furthermore, when the concrete is cracked, the modified liquid flows out of the inner cavity of the vermiculite and is adhered and cured at the crack to realize a self-repairing effect, so that the structural deformation of the tunnel can be better limited, and the service life of the tunnel lining in a complex environment is prolonged.

The invention relates to a comprehensive method for controlling non-stress cracks of a long concrete wall structure. The comprehensive method comprises the steps that S1, a construction flow section is divided; s2, low-early-stage elastic modulus concrete is poured at the bottom of the long wall to form a concrete transition layer, so that constraint on wall body concrete is reduced; s3, low-hydration-heat concrete is poured, and the temperature of the concrete entering a mold is controlled, so that upper concrete is formed; the low-early-stage elastic modulus concrete poured in the step S2 has the same strength grade as the low-hydration-heat concrete poured in the step S3, but the elastic modulus does not exceed 50% of the upper concrete poured at the same time within 48-72 h and does not exceed 70% in 7 d, the elastic modulus in 28 d is 90%-110% of the elastic modulus of the upper concrete, and the elastic modulus in 28 d is 90%-110% of the elastic modulus of the lower concrete. The low-hydration-heat concrete poured in the step S3 is prepared from moderate-heat cement or low-heat cement or by doping 35%-55% of fly ash into ordinary Portland cement, and the adiabatic temperature rise of the low-hydration-heat concrete is controlled to be not larger than 35 DEG C.

The invention relates to the technical field of concrete, and discloses a preparation method of high-strength concrete, which comprises the following steps: adding epoxy resin emulsion, cationic emulsified asphalt, aminopropyl acrylamide cardanol-based polystyrene and the like into water, shearing and dispersing, then adding cement, sand, fly ash and the like, stirring and mixing uniformly, vibrating and defoaming, curing and curing to obtain the high-strength concrete. The high-strength concrete is obtained. The aminopropyl acrylamide cardanol-based polystyrene disclosed by the invention contains an active imino group, can be subjected to a curing cross-linking reaction with epoxy resin to play a very good reinforcing role, and contains an alkenyl group, so that the aminopropyl acrylamide cardanol-based polystyrene can be subjected to a cross-linking reaction with unsaturated double bonds of asphalt at a high temperature to play a very good reinforcing role. The aminopropyl acrylamide cardanol-based polystyrene improves the compatibility between the epoxy resin and the cationic emulsified asphalt, improves the mechanical properties of the epoxy asphalt concrete, and shows higher axial compressive strength and compressive elastic modulus.

The invention relates to the field of material science, and discloses an asphalt concrete pavement segment joint anti-cracking method and system based on an odor removal technology, and the method comprises the steps: fitting a pavement segment joint model of a segment joint; analyzing a damage area and a fracture area of the pavement segment joint model, and analyzing a material stiffness modulus and a material relaxation modulus of the asphalt concrete; constructing a viscoelastic damage model of the asphalt concrete, calculating the viscoelastic damage coefficient of the asphalt concrete, and analyzing the asphalt viscoelasticity of the asphalt concrete; fitting a crack analysis model of the segment joint, and simulating pavement damage evolution of the segment joint; mixing the chemical additive and the asphalt concrete, and analyzing the viscosity effect of the geotechnical mixed material; and determining the optimal elastic modulus of the geotechnical mixed material, analyzing the anti-cracking effect of the geotechnical mixed material, and executing the anti-cracking scheme of the corresponding section joint of the asphalt concrete pavement. The anti-cracking effect of the asphalt concrete pavement segment joint can be improved.

The invention relates to a high-speed railway cement emulsified asphalt mortar mix proportion design method and system. The method comprises the following steps that design factors of cement emulsified asphalt mortar to be designed are input into a design model; the design factors comprise raw material types, usage and layout environment parameters; predicting and outputting a performance index corresponding to the to-be-designed cement emulsified asphalt mortar through the design model; the performance indexes comprise fluidity, expansion degree, working time, compressive strength, elasticity modulus and fatigue life; according to the performance indexes, the design factors of the cement emulsified asphalt mortar to be designed are adjusted and input into the design model, and the performance indexes corresponding to the adjusted design factors are obtained; and repeating the step of inputting and adjusting for multiple times until the optimal design factor meeting the performance requirement is obtained and output. The system and the equipment are used for executing the method. The method has the advantages of high design efficiency, short period, low cost and high accuracy.

The invention discloses a microcapsule as well as a preparation method and application thereof. The microcapsule comprises a capsule core and a capsule wall, the capsule core is wrapped in the capsule wall, the capsule core contains an active component, the elastic modulus of the microcapsule and the thickness of the capsule wall meet the following formula: Y = 0.42 X < 2 >-0.92 X + T, Y is the elastic modulus of the microcapsule, and the unit is GPa; x is the thickness of the capsule wall, and the unit is [mu] m; t is 1 + / -0.1; the elastic modulus of the microcapsule is obtained by testing the mechanical property of the microcapsule by adopting a nanoindentor, and the thickness of the capsule wall is obtained by testing the frozen section of the microcapsule by adopting a scanning electron microscope. The microcapsule provided by the invention is suitable for pavement asphalt, and can effectively improve the self-repairing efficiency of a pavement asphalt material; in addition, in the asphalt construction process, the emission of asphalt smoke can be effectively reduced, and the pollution to the environment is reduced.

The invention discloses freeze-thaw resistant concrete for roads in cold regions and a preparation method of the freeze-thaw resistant concrete, and relates to the technical field of concrete. The preparation method comprises the following steps: carrying out dry mixing on the Portland cement, the kaolin and the silicon carbide whiskers, then adding the coarse aggregate and the fine aggregate, continuing to stir and mix uniformly to obtain a premix, then adding the water reducer and the water into the premix, and continuing to stir uniformly to obtain the freeze-thaw resistant concrete. A proper amount of silicon carbide whiskers are added into the mixed soil, the mixed soil has high strength, high elastic modulus and excellent chemical stability, and the freeze-thaw cycle resistance of the concrete can be remarkably improved through the effects of bridging micro-cracks, blocking crack propagation paths, improving pore structures and the like.

The invention relates to the technical field of road engineering, in particular to a detection method for evaluating cohesion characteristics of river-crossing shield tunnel waste slag improved soil for roadbed filling, which comprises the following steps: preparing a solidified soil sample; calculating coupling parameters; obtaining a static cohesion force and a dynamic cohesion force; obtaining a water stability coefficient; based on the collected roadbed filling characteristic parameters, the static cohesion, the dynamic cohesion and the water stability coefficient, constructing a dynamic resilience modulus correlation model; grading the cohesion characteristics of the solidified shield soil according to the coupling parameters and the dynamic rebound modulus; detecting actual values of the coupling parameters and the dynamic resilience modulus of the to-be-evaluated solidified soil, and determining the grade of the to-be-evaluated solidified soil; according to the cohesion characteristic detection method, the characteristics of shield tunnel soil particles, mineral composition and roadbed filling scenes are fitted, actual working conditions are simulated, and the solidification effect is quantified, so that a scientific basis is provided for engineering application of shield tunnel soil solidification improved roadbed, and the problems in the background technology are effectively solved.

The invention belongs to the technical field of high-performance cement concrete, and particularly relates to low-shrinkage hybrid fiber concrete and a use method thereof. The low-shrinkage hybrid fiber concrete is prepared by mixing cement, fly ash, sand, gravel, steel fibers, synthetic fibers, water and a water reducing agent according to the mass ratio of (410 to 390): (70 to 100): (780 to 750): (900 to 1100): (95 to 65): 1.1: (150 to 160): (8.9 to 7.5). According to the invention, the dispersibility of the steel fibers and the synthetic fibers can be ensured, and the workability of concrete construction is ensured. Hybrid fibers of the concrete have high tensile strength, development of bridge deck concrete cracks is effectively delayed, the fracture resistance of the concrete is improved, the elastic modulus of the concrete is also improved, and therefore the axial tensile strength of the concrete is also obviously improved; meanwhile, the shrinkage performance of the concrete is effectively improved, the durability of the concrete is improved, the service life of the concrete is greatly prolonged, other stress structures of the bridge are effectively protected, and then the overall service life of the bridge is prolonged.

The invention relates to the technical field of concrete durability evaluation, in particular to a compound green concrete salt freezing resistance durability evaluation system under a frozen soil environment, which comprises a data input unit, a decision information table storage unit, a rough set analysis processing unit and an evaluation output unit, the data input unit receives a sample data set containing freeze-thaw cycle times, dry-wet cycle times, freeze-thaw-dry-wet cycle times, long-term soaking time, composite salt concentration, gas content and fly ash mixing amount, and the decision information table storage unit stores a decision information table constructed based on a rough set theory. The influence factor combination and the relative dynamic elastic modulus percentage are associated, the rough set analysis processing unit establishes a mapping relation through attribute reduction and rule extraction and quantifies the weight of each factor, and the evaluation output unit outputs a relative dynamic elastic modulus predicted value, durability grade classification and key factor contribution sorting. And the salt freezing resistance durability of the concrete under the multi-factor coupling effect is accurately evaluated.

A microcapsule, a preparation method therefor, and a use thereof. The microcapsule comprises a capsule core and a capsule wall. The capsule core is wrapped in the capsule wall. The capsule core contains an active ingredient. The elastic modulus of the microcapsule and the thickness of the capsule wall satisfy the following formula: Y=0.42X2-0.92X+T, wherein Y is the elastic modulus of the microcapsule, and the unit thereof is GPa; X is the thickness of the capsule wall, and the unit thereof is μm; and T is 1±0.1. The elastic modulus of the microcapsule is obtained by performing a mechanical property test on the microcapsule by using a nano-indentation instrument. The thickness of the capsule wall is obtained by performing frozen section on the microcapsule by using a scanning electron microscope. The microcapsule is suitable for pavement asphalt, and the self-repairing efficiency of a pavement asphalt material can be effectively improved. In addition, in a process of asphalt construction, the emission of an asphalt flue gas can be effectively reduced and the pollution to the environment is reduced.

The invention relates to a concrete filled steel tube arch bridge rib core ultra-high performance concrete mix proportion design method, which comprises the following steps: (1) taking slump, expansion and 28d compressive strength as response values, and adopting a response surface method to carry out mix proportion optimization design on a water-binder ratio and the composition of a cementing material to obtain the optimal value of the water-binder ratio and the composition of the cementing material; and (2) taking the slump, the expansion degree, the relative pressure bleeding rate, the segregation rate, the 28d compressive strength and the 28d elastic modulus as response values, and performing optimization design on the steel fiber mixing amount, the coarse aggregate and the binder ratio by adopting a response surface method to obtain the optimal values of the coarse aggregate substitution rate, the steel fiber volume mixing amount and the binder ratio. The concrete-filled steel tube core steel fiber ultra-high performance concrete mix proportion designed by adopting a response surface method can have good pumping performance under the condition of not performing high-temperature steam curing, and has the characteristics of high strength, high elastic modulus, micro-expansion and the like.

The invention discloses a non-dispersing agent for keeping concrete flowing in water, and belongs to the technical field of building materials, the non-dispersing agent comprises the following components by mass: 15-25% of an amphiphilic cellulose ether derivative; 10%-18% of a modified chitosan-acrylamide grafted copolymer; 8%-15% of a slow-release polycarboxylic acid water reducer; 5%-10% of nano silicon dioxide aerogel; 3%-8% of a bio-based delayed coagulation triggering agent; and 2%-5% of a self-repairing microbial capsule. Through a composite additive system, the loss rate of suspended solids is reduced to be within 1.2%, the slump loss within 2 hours is only 3%, and the problem of underwater segregation is solved; by utilizing a synergistic protection and self-repairing technology, the chloride ion diffusion coefficient is reduced by nearly 3 times, 0.3 mm cracks are repaired in 7 days, and the elastic modulus retention rate after freeze-thaw cycle reaches 91%. The underwater strength retention rate exceeds 95%, and the strength in 7 days reaches 80% of a design value. The ratio of the bio-based raw materials is 43%, the construction efficiency is improved by 87.5%, the cost in 30 years is reduced by 36.7%, and the method is widely applicable to environments and fills the blank of industrial test standards.

The present disclosure provides a rubber composition and a tire which can suppress changes in performances caused by changes in road conditions from dry to wet road surface or from wet to dry road surface. The tire of the present disclosure has E* when wet with water (MPa), E* when dry (MPa), tan δ when wet with water, tan δ when dry, 40% modulus (MPa) at 70° C. before a tensile test, and 40% modulus (MPa) at 70° C. after the tensile test which satisfy the following formulas (1) to (3):(1) E* when wet with water / E* when dry ≤0.90(2) tan δ when wet with water / tan δ when dry >1.00(3) 40% modulus at 70° C. after tensile test / 40% modulus at 70° C. before tensile test ≥0.45 whereE* and tan δ refer to a complex modulus of elasticity and a loss tangent, respectively, after 30 minutes from the start of measurement under the conditions of a temperature of 30° C., an initial strain of 10%, a dynamic strain of 1%, a frequency of 10 Hz, an elongation mode, and a measurement duration of 30 minutes;40% modulus at 70° C. after the tensile test refers to a tensile stress at an elongation of 40% determined after extension of 50% at 70° C., releasing the stress, and then measuring the tensile stress at an elongation of 40% at 70° C. in accordance with JIS K 6251:2010; and40% modulus at 70° C. before a tensile test refers to a tensile stress at an elongation of 40% measured before the tensile test at 70° C. in accordance with JIS K 6251:2010.

The invention relates to the technical field of nodular cast iron and an annealing method thereof, and discloses an annealing method for improving elastic modulus and strength of nodular cast iron and application, the annealing method comprises the following steps: first-stage annealing and high-temperature decomposition: heating to 880-980 DEG C along with a furnace, and preserving heat for 15-36 hours; second-stage annealing and low-temperature graphitization: cooling to 650-860 DEG C, preserving heat for 3-5 hours, and then quickly discharging from the furnace for air cooling; and performing surface treatment: performing shot blasting to remove oxide skin to obtain the nodular cast iron material. According to the scheme, the nodular cast iron material is prepared from the following raw materials in percentage by mass: 1.8 to 2.3 percent of C, 1.3 to 2.2 percent of Si, 0.3 to 0.7 percent of Mn, 0.002 to 0.005 percent of Bi, 0.002 to 0.01 percent of Sb, less than 0.06 percent of P, less than 0.2 percent of S and the balance of Fe. Compared with the prior art that two-stage annealing (such as furnace cooling to 595-635 DEG C after 900-950 DEG C treatment and heat preservation) needs to be matched with special components such as high rare earth and high phosphorus, the steps are complex and the cost is high, the phosphorus content and the rare earth content of the material in the scheme are low, the elastic modulus and the tensile strength of the nodular cast iron can be effectively improved by adding a proper amount of nodulizing agent, the production process is simplified, and the production cost is reduced. And the cost can be reduced.

The invention discloses a high-performance well cementation cement system for deep geothermal development, and relates to the technical field of well cementation materials for oil and gas field development. The well cementation cement system is prepared from the following components in parts by weight: 100 parts of a cementing material, 35 to 40 parts of a high-temperature reinforcing material, 7 to 10 parts of a high-thermal-conductivity toughening composite material, 0.5 to 1.5 parts of a suspension stabilizer, 0.3 to 0.6 part of a dispersing agent, 1.5 to 2.5 parts of a fluid loss agent, 1.0 to 2.5 parts of a retarder and 0.1 part of a de-foaming agent, the solid-to-liquid ratio of the well cementation cement system is 0.40 to 0.50. The high-temperature stability, corrosion resistance and long-term durability of the set cement can be guaranteed, and the heat conductivity of the set cement can be greatly improved. The cement slurry has the characteristics of higher high-temperature strength, low high-temperature strength decline rate, lower elastic modulus, high heat transfer efficiency and the like, can realize excellent engineering performance of the well cementation cement slurry under the condition of a hot dry rock high-temperature environment, and meets the engineering construction requirements.

A tire is provided which comprises a tread portion and a belt layer, wherein the tread portion has at least one rubber layer, the belt layer having a steel cord and a cap rubber covering the steel cord, a cap rubber layer forming a tread surface of the tread portion and the cap rubber are each composed of a rubber composition comprising a rubber component and a filler, wherein a complex elastic modulus at 70°C of the cap rubber (70°CE*1) is 15.0 MPa or less, and wherein in a case where W L in kg represents the maximum load capacity of the tire and 70 °C-tanδ1 represents a tanδ at 70 °C of the cover rubber, W L and 70 °C-tanδ1 satisfy the following inequality (1): 9.33 × 10 − 5 × WL − 70 ° C − tan δ 1 > 0.023

The present invention discloses a joint grouting reinforcement and repair technology for floors under soft soil geological conditions, and relates to the technical field of building floor reinforcement and repair. The present invention drills holes at the settlement of the building floor to install a polyurethane grouting pipe, injects a two-component polyurethane foaming agent under the floor, and injects foamed cement slurry in the gaps formed by lifting, so as to fill the gaps and make up for the defect of insufficient elastic modulus of the polyurethane material. The innovation of the present invention is to use polyurethane grouting reinforcement technology to solve the settlement problem of building floors under soft soil geological conditions. The injected two-component polyurethane and foamed cement slurry have a smaller bulk density than the soil, and the slurry remains in a floating state in the soil body and is not easy to flow downward; and the permeability coefficient of soft soil is extremely low, and the water in the injected foamed cement slurry is not easy to penetrate and lose, and the lifting force formed by grouting is not easy to dissipate through the drainage and consolidation of the environmental soil body. The secondary grouting uses foamed cement slurry, which greatly reduces the construction cost.

This invention relates to the field of concrete pouring technology, and discloses a method and system for regulating the cooling of hydration heat in large-volume concrete based on temperature difference control. The method includes the following steps: Step S101, constructing a thickness temperature profile; Step S102, calculating the zone temperature difference and the cooling rate in the middle section; Step S103, calculating the equivalent age field; Step S104, calculating the time-varying elastic modulus and relaxation time; Step S105, constructing a base constraint weighting function; Step S106, calculating the constrained viscoelastic thermal stress field; Step S107, calculating the potential energy centroid drift intensity; Step S108, outputting control commands. This invention achieves multi-factor coupled calculation and multi-objective collaborative optimization for regulating the cooling of hydration heat in large-volume concrete, ensuring that cooling regulation aligns with the core requirements of crack resistance in engineering projects, thereby reducing the possibility of hydration heat cracking in concrete.

The invention provides a concrete box girder damage assessment method under fire high temperature, and belongs to the technical field of road and bridge detection, and the method comprises the steps: determining the combustion time and fire scene temperature of a combustion source based on site fire investigation information and concrete apparent state; according to the combustion time and the fire scene temperature, the highest concrete temperature, the highest steel bar temperature and the highest steel strand temperature of the concrete box girder are determined; calculating the elasticity modulus and compressive strength of the concrete after the high temperature according to the highest temperature of the concrete; and determining the actual elastic modulus of the steel bar according to the highest temperature of the steel bar, and determining the actual elastic modulus of the steel strand according to the highest temperature of the steel strand. According to the method for evaluating the damage of the concrete box girder under the high-temperature action of the fire disaster, the fire scene condition can be evaluated more accurately, and then a scientific and systematic basis is provided for reinforcement and repair of the concrete box girder structure after the high temperature.

The invention discloses anti-freezing and salt-tolerant high-strength concrete and a preparation method and application thereof, and belongs to the technical field of green high-strength concrete preparation, the anti-freezing and salt-tolerant high-strength concrete comprises, by mass, 400-500 parts of a cementing material, 650-700 parts of fine aggregate, 1000-1100 parts of coarse aggregate, 0.01-0.015 part of an additive and 160-180 parts of water, the fine aggregate comprises machine-made sand and / or river sand, and the coarse aggregate comprises water and / or water. The mass of the machine-made sand accounts for 50% of the total mass of the fine aggregate. The compressive strength, elastic modulus, chloride ion penetration resistance and carbonization depth of the concrete are improved by adopting a double-doping (slag ash and fly ash) or triple-doping (fly ash, slag ash and silica fume) mode, and the concrete is excellent in freezing resistance, wear resistance and permeability resistance.

The invention discloses a method for quickly constructing a pre-stressed system of a post-tensioned pre-stressed cover beam in winter, and belongs to the technical field of cover beam construction. Comprising the steps that S1, a steel reinforcement framework, prestressed pipes, prestressed steel bars and the like are fixed according to a cover beam design drawing; s2, a plurality of wireless temperature sensors are arranged on the bent cap steel bars for temperature monitoring; s3, determining raw materials and dosage of capping beam concrete, and mixing the concrete; s4, the cover beam concrete is transported; s5, cover beam concrete is poured; s6, the whole process from pouring to hardening of the bent cap concrete is subjected to heat preservation and maintenance; s7, setting a temperature matching maintenance test piece, and determining a tensioning opportunity according to the compressive strength and the elastic modulus of the test piece; s8, selecting a grouting opportunity according to the temperature monitored by the wireless temperature sensor; and S9, quick-hardening phosphate mortar is selected, heating and heat preservation measures are applied, and anchor sealing concrete construction is conducted. According to the method, the winter construction speed of the post-tensioned prestressed cover beam can be increased, and the construction quality is guaranteed.

This invention discloses a method and equipment for evaluating the tensile toughness of recycled asphalt mixtures, relating to the field of analytical techniques for recycled asphalt mixtures. The method includes: acquiring variables related to the internal structure and external environment of the recycled asphalt mixture to be evaluated; the variables related to the internal structure include: internal structural state variables, the length of the aggregate-binder two-phase interface transition zone, and the elastic modulus; the variables related to the external environment include: tensile strain ratio, loading frequency, and dynamic modulus; and calculating the tensile toughness evaluation value of the cold recycled asphalt mixture based on a predetermined multi-parameter coupling relationship using the variables related to the internal structure and the external environment. This invention introduces environmental factors and internal structural parameters of the recycled asphalt mixture to establish a multi-parameter tensile toughness evaluation model, fully considering the material composition, microstructural distribution characteristics, load factors, and ambient temperature of the recycled asphalt mixture under stress in the structural layer, enabling accurate evaluation of the tensile toughness of the recycled asphalt mixture.

The present invention provides a method for testing micro-creep in a concrete interface transition zone, which relates to the field of mechanical testing technology. The method comprises using a nanoindenter to perform a nano-indentation test on a polished concrete sample to determine the boundary between the concrete sample aggregate, the interface transition zone, and the cement mortar, thereby obtaining the width of the interface transition zone; using a nano-indentation rectangular grid to assist in locating the coordinates of the indentation center of the micro-creep test; calculating the maximum load of the micro-creep test based on the water-cement ratio of the concrete, the width of the interface transition zone, the average elastic modulus in the interface transition zone, and the average elastic modulus in the cement mortar; and performing a micro-creep test on the micro-creep test area to obtain a contact creep function and a contact creep modulus of the interface transition zone. The present invention can accurately locate the indentation center of the micro-creep test in the concrete interface transition zone, and the test results obtained by the micro-creep test have low discreteness, and can accurately reflect the creep performance of the interface transition zone.

The invention belongs to the technical field of building materials, and relates to impermeable high-strength concrete and a preparation method thereof. The invention provides impervious high-strength concrete which is prepared from the following components in parts by mass: 150 to 200 parts of cement, 80 to 100 parts of organic and inorganic composite modified bentonite, 900 to 1300 parts of fine aggregate, 230 to 340 parts of coarse aggregate, 2 to 10 parts of additive and 250 to 350 parts of water, the organic and inorganic composite modified bentonite is obtained by modifying bentonite with polyepichlorohydrin dimethyl ammonium and then modifying the modified bentonite with hydroxyl polyaluminum chloride. The invention aims to solve the technical problem that the compressive strength and the elastic modulus of the concrete for the underground diaphragm wall are almost synchronously reduced along with the increase of the use amount of bentonite, so that the compressive strength and the elastic modulus are difficult to consider at the same time.

The invention relates to the technical field of engineering materials, and provides anti-cracking steel slag asphalt concrete and a preparation method thereof. The anti-cracking steel slag asphalt concrete is prepared from, by weight, 4-6 parts of asphalt, 5-10 parts of filler and 60-70 parts of aggregate, the filler is prepared from, by weight, 20-30 parts of steel slag powder, 20-25 parts of limestone powder, 0.3-0.5 part of polypropylene fiber and 0.3-0.5 part of dispersing agent, and the polypropylene fiber is composed of first polypropylene fiber and second polypropylene fiber. The elastic modulus and the fiber length of the first polypropylene fiber are different from those of the second polypropylene fiber. According to the technical scheme, the problem of insufficient cracking resistance of the steel slag asphalt concrete in related technologies is solved.

The application discloses a kind of shotcrete and its preparation method, belong to building material technical field.It mainly includes the following weight parts of raw materials made: Portland cement 200~260 parts, fine sand 240~280 parts, 260~300 parts of gravel, fly ash 10~35 parts, composite steel fiber 5~10 parts, admixture 10~15 parts, no alkali accelerator 2~5 parts, water reducing agent 1~3 parts and water 80~110 parts.The shotcrete provided by the application adopts steel fiber and has excellent tensile strength and elastic modulus and other characteristics, and the composite steel fiber forms a three-dimensional network structure in the concrete to support the concrete;After adding fly ash and admixture to the concrete, it is beneficial to improve the compactness of the concrete, promote the development of early strength, and improve the compressive performance of the concrete.

The application discloses an interface adhesive as well as a preparation method and application thereof, and belongs to the technical field of concrete. A component A contains E-51 epoxy resin, elastic modulus enhancer a (a composite of single-sulfur calcium sulphoaluminate and high-sulfur calcium sulphoaluminate) and bonding enhancer b (nanoscale gel), etc.; a component B is a polyamide curing agent and a modified aromatic amine curing agent. The adhesive has an elastic modulus of about 40 GPa, is between UHPC and NC, can relieve interface stress concentration, can permeate and block microcracks at the same time, and can significantly improve bonding strength and durability. When the adhesive is prepared, the component A and the component B are stirred respectively, are mixed in proportion, and are vacuum degassed, and the adhesive is obtained. When the adhesive is constructed, the adhesive is coated on the surface of existing ordinary concrete first, and then an ultrahigh performance concrete reinforcing layer is poured.

The application discloses an anti-impact and abrasion material and a preparation method thereof. The anti-impact and abrasion material is prepared from the following components in parts by weight: 40-45 parts of low-heat Portland cement with a strength grade not lower than 42.5, 8-13 parts of mineral admixture, 2-5 parts of barium sulfate, 37-43 parts of fine aggregate, 0.2-0.5 parts of water reducing agent, 0.1-0.3 parts of wetting agent, 0.1-0.8 parts of coagulant, 0.01-0.05 parts of reactive air-entraining material, 0.1-0.3 parts of air bubble inhibitor, 0.1-0.5 parts of nanometer material, 0.3-1.0 parts of redispersible latex powder, 2-5 parts of modified organic aggregate, 0.01-0.05 parts of cellulose ether, 0.3-0.8 parts of composite fiber, 1.0-3.0 parts of internal water-retaining agent and 14-18 parts of water. The application reduces the elastic modulus of the material and improves the impact toughness of the material under the premise of ensuring the crack resistance of the material, and the material is high-strength and dense, and can resist the impact and abrasion damage of media.