1234 results about "Crack resistance" patented technology

The present invention proposes an intermediate diaphragm-free, suspended formwork-free, and negative moment tooth block-free beam bridge, and a design method thereof. The beam bridge includes prefabricated main girders, a wet joint, lower structures, and pier cap transverse beams above the lower structures. The concrete deck slabs of adjacent prefabricated main girders are connected by the wet joint. The design method of the above beam bridge includes the following steps: S1, initial design of the main girders; S2, calculation of the non-uniform deflection of the main girders and the indirect transverse stress of the deck slabs; S3, calculation of the direct transverse stress of the deck slabs; S4, crack resistance verification of the deck slab; S5, optimization of bridge parameters to reduce the stress on the driving surface; S6, completion of the beam bridge design. The beam bridge and its design method effectively solve the problem that the existing intermediate diaphragm-free beam bridge is prone to longitudinal cracking at the joints, and realize the suspension tension without the wet joint suspended formwork of the deck slab and the negative bending moment tendon, and have better mechanical properties and better economic, environmental and social benefits, which can facilitate the promotion and application of such bridges in various types of highways , railways and municipal engineering.

The invention provides a method for evaluating the crack resistance of tunnel body concrete, and belongs to the technical field of wind tunnels, and the method comprises the steps: uniformly arranging multiple types of sensors on the surface of a tunnel body concrete structure to form a high-density monitoring network, employing a concrete circular ring constraint test piece to establish an anti-crack reference database, and constructing a multi-working-condition temperature stress database; acquiring multi-dimensional data such as strain, temperature and acoustic emission in real time, inputting the monitoring data into a liquid adaptive neural network model to predict crack initiation probability and expansion risk, establishing a crack risk assessment function, formulating a corresponding processing strategy according to a risk coefficient range, and starting an intelligent spray maintenance system; a closed-loop control system from monitoring perception to risk early warning to active protection is formed, and the technical problem that crack initiation and expansion risks of a hole body concrete structure cannot be accurately predicted under complex working conditions is solved.

The invention belongs to the technical field of motor casing lost foam casting, and particularly relates to a special coating for a motor casing lost foam as well as a preparation method and application thereof. Through a quantitative formula design method, an aggregate proportion calculation formula based on thermal expansion coefficient matching and a grain size distribution correlation formula based on target air permeability, cooperative compounding of quartz powder and bauxite is achieved, and key functional components such as mullite, organic matter fibers and crystalline flake graphite are combined; the unification of high air permeability and excellent crack resistance of the motor shell lost foam coating is realized. The invention further provides a two-time coating gradient drying efficient process matched with the coating, and on the premise that the coating performance is guaranteed, the production efficiency is remarkably improved, and the energy consumption is reduced.

The invention discloses steel, a steel pipe for hydrogen conveying and a preparation method of the steel pipe, and belongs to the technical field of pipelines. The steel comprises, by mass, not larger than 0.05% of C, 0.1%-0.3% of Si, 0.8%-1.3% of Mn, not larger than 0.02% of P, not larger than 0.01% of S, not larger than 0.03% of Al, not larger than 0.35% of Ni, not larger than 0.3% of Cr, not larger than 0.25% of Cu, not larger than 0.05% of V, not larger than 0.1% of Nb, not larger than 0.3% of Mo, not larger than 0.04% of Ti, not larger than 0.0003% of B and the balance Fe. The steel is suitable for preparing the hydrogen conveying pipeline, so that the steel is good in compatibility with the hydrogen environment and has the characteristics of excellent hydrogen induced cracking resistance, strength and toughness.

The invention provides low-temperature-resistant high-modulus rubber asphalt and a preparation method thereof, and relates to the technical field of rubber asphalt, and preparation raw materials of the low-temperature-resistant high-modulus rubber asphalt comprise the following components: matrix asphalt, rubber powder, a desulfurizer, a free radical type thermal initiation crosslinking agent, a reinforcing agent, a coupling agent, a flexibilizer, a viscosity reducer and an auxiliary agent. According to the low-temperature-resistant high-modulus rubber asphalt provided by the invention, the ductility at 5 DEG C is greater than 30cm, the maximum breaking flexural-tensile strain of a mixture at-10 DEG C is greater than 4000 mu epsilon, the dynamic modulus of the mixture at 15 DEG C is greater than 15000MPa, and the high-temperature performance and modulus of high-modulus asphalt concrete are not reduced while the crack resistance of the high-modulus asphalt concrete is helped to be improved. When being applied to pavement middle layer pavement, the pavement anti-cracking agent can improve the anti-cracking performance of the whole pavement structure, reduce the pavement maintenance cost and improve the driving safety.

The invention relates to the technical field of engineering performance intelligent detection, in particular to a concrete main tower circumferential prestressed reinforcement anti-cracking prediction method based on machine learning, which is characterized in that fiber grating strain sensors are arranged on the sections of main tower circumferential prestressed reinforcements, and strain data and environmental parameters in tensioning and operation stages are acquired; marking a cracking state to construct a sample data set; carrying out adaptive segmentation and abnormal value elimination operation on the strain sequence to realize data cleaning; constructing a cracking probability prediction model to process the cleaned data to obtain a cracking prediction probability; and calculating the total loss of the model, training the model, inputting newly collected data into the trained model, outputting a cracking prediction probability, and judging whether to carry out early warning or not. According to the method, online, real-time, intelligent and accurate prediction of the cracking risk of the circumferential prestressed steel bars of the concrete main tower can be realized, the monitoring false alarm rate is effectively reduced, and reliable technical support is provided for bridge operation maintenance and safety management and control.

The invention relates to the technical field of polyolefin cable materials, in particular to a photovoltaic weather-resistant anti-cracking low-smoke halogen-free flame-retardant polyolefin cable material and a preparation method thereof.The photovoltaic weather-resistant anti-cracking low-smoke halogen-free flame-retardant polyolefin cable material is prepared from, by weight, 90-150 parts of polyolefin resin, 1-3 parts of antioxidant, 2-5 parts of ultraviolet light absorber, 30-70 parts of composite flame retardant, 10-25 parts of carbon black and 3-5 parts of cross-linking agent; the composite flame retardant comprises a core material, a first shell material and a second shell material, the core material comprises a halloysite nanotube adsorbed with a flame retardant, the first shell material comprises epoxy resin, and the second shell material comprises maleic anhydride grafted polyethylene. According to the polyolefin cable material provided by the invention, the purpose of efficient flame retardance can be achieved by adding the halloysite nanotubes and the flame retardant system, the interfacial compatibility between the flame retardant and the matrix resin can be improved by adding the maleic anhydride grafted polyethylene, and the flame retardance of the polyolefin cable material can be improved by combining the added halloysite nanotubes and epoxy resin. The purpose of improving weather resistance, stress resistance and crack resistance of matrix resin is achieved.

The invention discloses a super-early-strength shrinkage-free high-crack-resistance tunnel spraying repair material in the technical field of civil engineering materials, which comprises the following raw materials in percentage by mass: 35-45% of sulphoaluminate cement; 8%-12% of a superfine early strength admixture; 2%-3% of a calcium sulphoaluminate expanding agent; 1%-2% of a magnesium oxide-based expanding agent; 1-2% of a calcium-magnesium composite expanding agent; 10%-15% of hollow glass beads; 1.5%-2.5% of copper plated steel fiber; 0.1%-0.3% of polypropylene fiber; 25%-30% of graded quartz sand; 0.5%-1.0% of a polycarboxylic acid water reducing agent; 3%-5% of an alkali-free liquid accelerator; 0.3%-0.8% of a thixotropic agent; and 0.1%-0.3% of a thickening time control agent. According to the method, a multi-scale performance cooperative regulation system is innovatively constructed. Through accurate control of the hydration process of a gel system, a shrinkage stress multi-stage compensation mechanism and systematic integration of a fiber-matrix interface strengthening technology, the mutual restriction relationship among early strength development, volume stability and crack resistance of a traditional material is broken through.

The invention discloses a polymer emulsion composite modified road base material and a preparation method thereof, and belongs to the technical field of traffic infrastructure engineering materials. The polymer emulsion composite modified road base material is prepared from the following raw materials: graded aggregate, super sulfate cement or geopolymer cement, water for mixing, vinyl acetate-ethylene (VAE) copolymer emulsion and a silane coupling agent. The preparation method comprises the following steps: mixing the VAE emulsion with water for mixing to obtain a polymer diluent; mixing graded aggregate with an inorganic cementing material, then adding the polymer diluent, and mixing to obtain a mixture; and then paving, compacting, forming and curing are carried out. By forming a VAE flexible network-C-S-H / ettringite hybrid network, the material has the remarkable advantages of higher mechanical strength and low cost, and can greatly improve and enhance the crack resistance and durability of the road base.

The invention provides rubber-plastic composite modified asphalt suitable for low-temperature regions and a preparation method thereof, and belongs to the technical field of modified asphalt preparation. The modified asphalt is prepared from matrix asphalt, rubber powder, polyethylene and a compatibilizer, the content of the rubber powder is 15%-25% of the weight of the matrix asphalt, the content of the polyethylene is 4%-6% of the weight of the matrix asphalt, and the content of the compatibilizer is 5%-15% of the weight of the matrix asphalt; the preparation method comprises the following steps: heating the matrix asphalt to a flowing state, adding the rubber powder, stirring and swelling for 60 minutes, adding the polyethylene and the compatibilizer, stirring, and shearing at a high speed of 5000r / min for 45-60 minutes. Through rubber and plastic compound modification, the low-temperature crack resistance, the high-temperature stability and the water stability are excellent, the storage stability is good, the cost and pollution are reduced by utilizing waste materials, the process is simple, and the low-temperature road pavement material is suitable for road engineering in low-temperature areas.

The invention discloses self-repairing concrete based on modified carbon fibers and a preparation method thereof, and belongs to the technical field of building materials. An existing concrete crack repairing technology has two major problems that bonding between carbon fibers and a matrix is poor, and the repairing effect is limited; microbial self-repairing and nutrient adding can reduce the strength of the concrete. According to the solution provided by the invention, firstly, the surface of the carbon fiber is modified by an MICP method to form a stable three-dimensional calcium carbonate coating layer, so that the surface roughness is enhanced, the interface bonding capacity of the carbon fiber and a gelling matrix is greatly improved, and the carbon fiber is stably attached to an interface; then, the modified carbon fibers and concrete raw materials are accurately mixed according to a specific proportion, and the high-strength and good-crack-resistance self-repairing concrete is prepared. When cracks are generated, the carbon fibers limit crack propagation with high strength and high ductility, and surface microorganisms generate calcium carbonate through physiological reaction to fill the cracks; the strength, crack resistance and self-repairing capacity of a concrete structure are improved, the service life is prolonged, and the concrete is suitable for a hydraulic concrete structure in a complex environment and wide in application prospect.

The invention relates to the technical field of special functional coating materials for lost foam casting, and particularly discloses a special coating for a large machine tool casting lost foam as well as application and a use method of the special coating. According to the invention, the full-temperature-range functional composite material and the composite aggregate are used for synergistic reinforcement, and mullite is used for high-temperature reinforcement; the temperature-sensitive polymer modified graphite can realize intelligent temperature response of graphite performance; spodumene is used as a thermal expansion adaptive fluxing agent, so that medium-temperature healing and thermal expansion adjustment of a coating system are facilitated; the composite reinforced fibers are reinforced and toughened aiming at large thermal stress of thick and large parts; as an ultralow-temperature glazing agent, the boron-containing glazing agent can form an initial liquid phase at about 450 DEG C to seal the surface of the coating and purify a ventilation channel; the rare earth oxide serving as a high-temperature phase stabilizer can be dissolved in mullite crystal lattices, so that the high-temperature phase stability is improved, and ceramic nodes are refined. Through raw material design, on the premise of ensuring moderate air permeability, the ultrahigh strength and crack resistance of a coating system at extremely high temperature are improved.

The invention relates to the technical field of pipeline steel for oil and gas transmission, in particular to a novel low-C low-Cr corrosion-resistant pipeline steel plate, a preparation method and a pipeline steel pipe, and the novel low-C low-Cr corrosion-resistant pipeline steel plate comprises the following chemical elements: less than or equal to 0.03 wt% of C, less than or equal to 0.025 wt% of Sb, 0.50-1.20 wt% of Al, 0.0005-0.0012 wt% of Mg, 0.0012-0.0042 wt% of Ca, less than or equal to 0.50 wt% of Cr, 0.10-0.30 wt% of Ni, 0.10-0.30 wt% of Si, 1.20-1.80 wt% of Mn, 0.10-0.30 wt% of Mo, 0.02-0.06 wt% of Nb, 0.03-0.08 wt% of V, 0.01-0.03 wt% of Ti, less than or equal The manufactured steel plate is low in manufacturing cost, excellent in yield strength, tensile strength, ductility, impact toughness, corrosion resistance, hydrogen induced cracking resistance and other mechanical properties and suitable for seabed and land oil and gas conveying pipeline engineering in the high Cl <-> and CO2 / H2S corrosion environment.

The invention relates to the technical field of hydraulic concrete materials, and particularly discloses nano-modified anti-rebound full-hole slag sprayed concrete, which is prepared from the following raw materials in parts by weight: 665 parts of hole slag aggregate, 950 parts of hole slag sand, 396 to 436.5 parts of ordinary Portland cement, 225 parts of water, 10 parts of polycarboxylic acid type water reducing agent and 8.5 parts of accelerator, the hole slag aggregate is further modified by a nano admixture, and the nano admixture is composed of nano kaolin, nano silicon dioxide and a precise PCE solution. The springback-resistant shotcrete is prepared from the nano admixture modified hole slag aggregate, full-quantitative resource utilization of tunnel excavation hole slag is achieved, the problems of occupied area of piled slag and potential ecological pollution are effectively relieved, the cement consumption in the concrete is reduced, the construction cost is reduced, meanwhile, the springback rate of the shotcrete can be remarkably reduced, and the construction period is shortened. The compactness of the concrete is improved, and the compression resistance degree and the crack resistance of the concrete are enhanced.

The invention relates to the technical field of concrete, and provides anti-crack concrete and a preparation method thereof.The anti-crack concrete is prepared from, by weight, 280-350 parts of cement, 50-80 parts of mineral admixture, 1000-1200 parts of gravel, 650-850 parts of sand, 6.0-10.0 parts of water reducing agent, 16-20 parts of expanding agent, 10-25 parts of fiber and 140-160 parts of water; the fiber is a nano-modified PVA fiber and is formed by grafting SiO2 nano-particles with the particle size of 20 nm on the surface of the PVA fiber, and the grafting amount is 3%-5%. The PVC fibers are subjected to nano modification, SiO2 nanoparticles with the particle size of 20 nm are grafted to the surfaces of the PVC fibers, a low-surface-energy dispersion layer is formed on the surfaces of the PVA fibers, the agglomeration resistance of the PVA fibers is improved, agglomeration generated when the PVC fibers are used for preparing the anti-crack concrete is reduced, and then the anti-crack performance of the concrete is improved.

The invention relates to the field of building materials, and discloses high-toughness and high-energy-absorption polymer emulsion modified mortar and a preparation method thereof, and the mortar is composed of ordinary Portland cement, river sand, a polymer emulsion, water, an active admixture and chopped fibers. Wherein the polymer emulsion is selected from styrene-acrylic emulsion (SBR), ethylene-vinyl acetate (EVA), polyurethane emulsion or a combination thereof; the mixing amount is 5-20wt% of the mass of the cementing material. According to the invention, a viscoelastic network is formed in a cement matrix through the polymer emulsion, and the synergistic effect of the active admixture and the chopped fibers is combined, so that the bonding strength, the crack resistance, the impact resistance and the stress wave dissipation capability of the mortar are remarkably improved. Test results show that the mortar provided by the invention is obviously superior to ordinary mortar in the aspects of 28d breaking strength, impact toughness and stress wave attenuation performance, and is suitable for high-performance constructional engineering and protective engineering.

The invention relates to the technical field of building materials, in particular to a high-elasticity polyurethane-asphalt composite road crack repair material and a preparation method thereof, and the high-elasticity polyurethane-asphalt composite road crack repair material comprises the following raw materials: an asphalt-based material, functional modified polyurethane, a polyether-polyolefin block copolymer, functional rubber, 2, 6-di-tert-butyl-4-methylphenol and sodium polyacrylate. According to the invention, a lipophilic functional group is introduced into a molecular chain of the functionalized modified polyurethane, so that the functionalized modified polyurethane can interact with alkyl in asphalt to form a more stable synergistic network structure, and the phase separation phenomenon of the polyurethane and the asphalt is effectively reduced; the modified polyurethane not only improves the elasticity, flexibility, temperature resistance and crack resistance of the composite material, but also optimizes the processability of the material, enhances the interface bonding force, and further improves the repair effect and the road durability.

The invention belongs to the technical field of batteries, and particularly relates to a negative plate and a preparation method and application thereof. The negative electrode plate comprises a negative electrode current collector and a negative electrode material layer arranged on at least one side surface of the negative electrode current collector, the negative electrode material layer comprises a negative electrode active substance, a negative electrode conductive agent and a composite binder, and the composite binder comprises carboxymethyl cellulose lithium and siloxane. The negative electrode plate has relatively high stripping force or crack resistance, and the first coulombic efficiency or cycle stability of the battery can be effectively improved when the negative electrode plate is applied to the battery.

The invention relates to the technical field of water-stable layer materials, in particular to a microcapsule self-repairing ardealite water-stable layer material and a preparation method and application thereof.The preparation method comprises the following steps that S1, ardealite, slag powder and a modified coagulant are mixed in a mixer, and a preliminary modified mixture is obtained; s2, adding double microcapsules into the primary modified mixture to obtain a secondary modified mixture; s3, adding deionized water into the modified mixture obtained in the step S2, and stirring and mixing to obtain a modified wet mixture; and S4, injecting the modified wet mixture into a mold, vibrating to remove bubbles, standing at room temperature, and demolding and curing for 25-28 days to obtain the microcapsule self-repairing phosphogypsum water-stable layer material. Through the synergistic effect of the double microcapsules and the modified coagulant, the integrated function of rapid coagulation, self-repairing and toughness enhancement is achieved, it is guaranteed that a strength framework is rapidly formed in a high-humidity environment, meanwhile, immediate repairing can be provided for micro-damage, and the toughness and crack resistance of the material are macroscopically improved.

The invention relates to the technical field of concrete, and particularly discloses low-temperature-resistant self-repairing waterproof concrete for water conservancy and a preparation method of the low-temperature-resistant self-repairing waterproof concrete. The water conservancy low-temperature-resistant self-repairing waterproof concrete is specifically prepared from the following components in parts by weight: 70 to 80 parts of cement, 10 to 20 parts of fly ash, 8 to 12 parts of silica fume, 2.5 to 3.5 parts of a reinforcing material, 0.2 to 0.4 part of a crystallization inducer, 1.5 to 2.5 parts of a repairing agent and 20 to 40 parts of water, the reinforcing material is formed by mixing nano silica sol, bentonite, quartz sand and triethanolamine; the crystallization inducer is formed by mixing sodium silicate and aluminum hypophosphite; the repairing agent is obtained by loading calcium ions on an amino silane modified zeolite material and then mixing with a bacillus pasteurii bacterial solution. By utilizing the technical scheme provided by the invention, the prepared concrete has excellent mechanical properties, water resistance, impermeability, freezing resistance, crack resistance and good durability.

The invention discloses basalt fiber reinforced low-carbon environment-friendly asphalt and a construction method of the basalt fiber reinforced low-carbon environment-friendly asphalt on a high and cold road surface, and relates to the technical field of road engineering. The basalt fiber is subjected to ultrasonic treatment by a silane coupling agent KH-550 hydrolysate and dried, and the low-carbon additive is prepared from waste rubber powder and biological asphalt and is matched with an anti-stripping agent; adding biological asphalt, stirring at a high speed, adding basalt fibers in three times, stirring at a high speed, and finally adding an anti-stripping agent to prepare an asphalt composition; adding an asphalt composition for wet mixing, and then adding fibers for continuous mixing to obtain a mixture; after the lower bearing layer is preheated, a crawler-type paver paves at the temperature of 155-165 DEG C, and the speed and the loose paving coefficient are controlled; initial pressing, re-pressing and final pressing are carried out, and a double-steel-wheel and rubber-wheel road roller is used for rolling according to the temperature and the speed; and after compaction, the heat-insulating tarpaulin is covered. The low-temperature crack resistance and freeze-thaw resistance of the basalt fiber reinforced asphalt, the carbon emission reduction of the waste rubber powder and the biological asphalt and the construction quality guarantee through dynamic temperature control and intelligent compaction are realized, and the construction method is adaptive to the alpine regions and meets the requirements of green road construction.

The invention relates to the technical field of road engineering, in particular to an all-solid waste rubber-based composite modified foam cold recycled asphalt mixture and a preparation method thereof, and the all-solid waste rubber-based composite modified foam cold recycled asphalt mixture comprises the following components in parts by mass: 150-200 parts of graded precisely-controlled recycled aggregate, 10-25 parts of recycled mineral activity enhancing powder, 5-10 parts of an industrial solid waste reinforcing agent and 20-40 parts of solid waste-based recycled foam asphalt. The mixture utilizes various solid wastes for recycling, has excellent pavement performance, high strength, crack resistance and durability, can be constructed at normal temperature or low temperature, and is low in energy consumption and environment-friendly. Through composite modification of foamed asphalt and rubber powder, early strength and stability are significantly improved, the problem of slow development of early strength of a cold recycled material is overcome, the construction period is shortened, and traffic is quickly opened. The method is simple in process, low in cost and convenient to construct, meets the requirements of green and low-carbon construction, provides a new way for the double-carbon target in the traffic field, and is remarkable in economic and social benefits and wide in application prospect.

The invention discloses a strong hydrophobic type composite concrete waterproofing agent as well as a preparation method and a use method thereof. The waterproofing agent is prepared from 14-18 parts of a hydrophobic / temperature-inhibiting composite active component, 2-3 parts of a silane coupling active component, 2-3 parts of an emulsifying active component, 4-6 parts of a complexing active component, 8-10 parts of a crystallizing active component and 60-70 parts of water. The polyorganosiloxane / paraffin composite emulsion is synthesized in one step by co-emulsifying polyorganosiloxane and paraffin, and other functional active components are compounded, the preparation method provided by the invention is simple to operate, and the prepared waterproof agent system is stable and has the following beneficial effects after being doped into concrete: 1, the hydrophobicity of the concrete is remarkably improved; 2, excellent crystallization performance helps self-healing of concrete microcracks, and the impermeability of concrete is significantly improved; and 3, cracks caused by too fast temperature rise of initial hydration heat of the concrete are effectively inhibited, and the crack resistance of the concrete is remarkably improved.

The invention relates to the field of building materials, in particular to high-durability and high-permeability-resistance mortar and a preparation method thereof.The high-durability and high-permeability-resistance mortar is prepared from, by weight, 40-60 parts of cement, 20-40 parts of quartz sand or machine-made sand, 10-20 parts of fly ash or mineral powder, 2-5 parts of polymer emulsion, 1-3 parts of an anti-permeability agent, 0.2-1 part of a water reducing agent, 0.1-0.5 part of a water-retention thickening agent and water; wherein the water cement ratio is controlled to be 0.30 to 0.35. Through collaborative optimization of multiple components, the compactness, impermeability, crack resistance and durability of the mortar are remarkably improved, the preparation process is simple and convenient, the raw materials are easy to obtain, and the mortar has excellent comprehensive performance and wide application prospects.

The invention provides a real-time data driving-based mortar microstructure regulation and control method, which comprises the following steps of: acquiring flow state data of a mortar material in real time in a construction process through a sensor network, recording internal stress distribution and a particle movement track of the material, and generating an initial flow state data set; if the structure distribution data set does not reach the target threshold value, dynamically adjusting the external intervention intensity through a feedback control module, recalculating vibration or electromagnetic guide parameters in combination with real-time monitoring data, and generating an improved intervention strategy; and for the improved intervention strategy or the material reaching the target threshold value, continuously monitoring the mechanical property index after molding, recording related data of crack resistance and flexibility improvement, and generating a comprehensive performance evaluation result.

The invention discloses a gradient combination anti-crack diaphragm wall concrete self-constraint stress optimization design method. The method comprises the following steps: firstly, constructing a BIM three-dimensional structure model comprising material performance, temperature gradient and stress state through three-dimensional laser scanning and core sample detection; then, carrying out stress partitioning based on the model, and calculating a self-constraint stress value and a stress transfer attenuation coefficient of each partition; then establishing an expanding agent proportion optimization model, simulating stress redistribution under different doping amount gradients by adopting a finite element algorithm, and screening a minimum effective doping amount meeting a stress homogenization index; and after the anti-cracking effect is verified through dynamic simulation, a final matching scheme is output. According to the method, the BIM technology and the material gradient design are combined, precise control over the concrete self-constraint stress of the underground diaphragm wall and active optimization of the crack resistance are achieved, the technical problem that traditional homogeneous material design is difficult to adapt to complex stress distribution is solved, and the durability and safety of the underground diaphragm wall structure are remarkably improved.

The invention relates to the technical field of structural health monitoring and safety evaluation, and discloses an acoustic emission-microwave fused concrete crack resistance monitoring method, which comprises the following steps: S1, data acquisition: acquiring an acoustic emission signal and a microwave signal of a concrete structure; s2, a signal preprocessing step: performing noise reduction, feature extraction and environment compensation on the acoustic emission signal and the microwave signal; and S3, data fusion: fusing the acoustic emission signal and the microwave signal by adopting a Bayesian optimization method. The invention further provides an acoustic emission-microwave fusion concrete anti-cracking performance monitoring device and an acoustic emission-microwave fusion concrete anti-cracking performance monitoring system. Through dynamic monitoring adjustment, an environment correction prediction model and a structural stability evaluation method, accurate tracking of crack propagation, intelligent prediction of long-term trend and quantitative evaluation of bearing capacity are realized, and the real-time performance, accuracy and comprehensiveness of structural health monitoring are improved.

The utility model relates to the field of concrete detection platforms, in particular to a basalt fiber concrete crack resistance detection platform which comprises a detection cabinet and supporting legs fixed at the lower end of the detection cabinet, a through groove is formed in the upper end of the detection cabinet in a penetrating mode, and a rotating module for adjusting the angle of concrete is installed in the detection cabinet. To-be-detected concrete is placed at the upper end of the rotating module, a moving module is arranged at the upper end of the detection cabinet, a top plate is installed in the moving module, a first hydraulic cylinder is installed at the lower end of the top plate, and a pressing block for applying pressure to the concrete is installed at the power output end of the first hydraulic cylinder. A rotating shaft is rotatably connected in the first bearing seat, an inclined plate is fixedly connected to the upper end of the rotating shaft, a fan is mounted on the inclined surface of the inclined plate, a rotating assembly is mounted at the upper end of the detection cabinet, and the rotating shaft adjusts the angle of the fan through the rotating assembly; according to the utility model, the solidification process of concrete is accelerated, and the position of the pressing block and the angle of the concrete can be easily adjusted.

The invention discloses sound insulation mortar, a preparation method, a sound insulation mortar system and a construction technology, and belongs to the field of building materials. The phosphogypsum-based low-carbon thermal insulation and sound insulation mortar is prepared from the following raw materials in parts by weight: 50 to 60 parts of phosphogypsum, 20 to 30 parts of filler, 10 to 15 parts of inorganic admixture, 10 to 15 parts of glass beads, 5 to 10 parts of aerogel, 0.1 to 0.5 part of water-retaining agent, 1 to 4 parts of polymer rubber powder, 0.02 to 0.05 part of retarder and 0.2 to 0.5 part of water reducing agent. The ardealite-based low-carbon thermal insulation and sound insulation mortar is compact in structure and good in crack resistance, and has an excellent sound insulation effect on the premise of ensuring that the mechanical property reaches the standard. The thermal-insulation and sound-insulation material is good in fire resistance and outstanding in aging resistance and durability in the long-term use process, has convenient construction performance and can fully meet the comprehensive use requirements of constructional engineering for thermal-insulation and sound-insulation materials.

The utility model discloses a local variable stiffness enhanced welding stud shear connector and a steel-concrete combined track beam. The connector comprises a thickened bottom rod, a slender middle rod and a cylindrical head which are connected in sequence, the diameter of the thickened bottom rod is greater than that of the slender middle rod; the cylindrical head is larger in diameter than the elongated middle rod. The steel-concrete combined track beam comprises a UHPC cast-in-place bridge deck slab, a local variable stiffness enhanced welding stud shear connector and a track steel beam, and the local variable stiffness enhanced welding stud shear connecting piece is welded on the top surface of the track steel beam and is used for connecting the track steel beam with the UHPC cast-in-place bridge deck at the upper part. The connecting piece has the advantages of being suitable for the steel-concrete combined track beam and aiming at solving the problems that a traditional shearing force connecting piece is insufficient in shearing bearing capacity under the complex dynamic load environment, a concrete panel is prone to cracking and the like, and therefore the overall bearing capacity, durability and anti-cracking performance of the track beam are improved, and the quality and efficiency of the cast-in-place construction technology are optimized.