582 results about "Concrete composites" patented technology

The invention discloses an intelligent concrete composite material and a preparation method thereof. The material is formed by compounding a base material, a microencapsulated phase change material, a self-repairing agent and reinforced fibers. The microencapsulated phase-change material is of a core-shell structure, the core of the microencapsulated phase-change material is an organic phase-change substance, and the shell of the microencapsulated phase-change material is a polymer wall material; the self-repairing agent is a two-component microcapsule system containing a healing agent and a catalyst. When the building material is damaged by external force to generate microcracks, the stress at the tip of the cracks can enable the self-repairing microcapsules to be broken, the released healing agent is polymerized under the action of the catalyst, and self-repairing of the cracks is achieved. Meanwhile, the phase change material in the material can absorb or release a large amount of heat through phase transition, the internal temperature of a building is effectively adjusted, and energy consumption is reduced. The preparation process is simple, the cost is low, and the obtained material is excellent in comprehensive performance and has a wide application prospect.

The invention provides a method for analyzing anti-seismic performance of a steel reinforced concrete frame structure in a construction process, which comprises the following steps: S1, establishing a time-varying calculation model of the steel reinforced concrete frame structure in the construction process, the time-varying calculation model being used for simulating structural incompleteness and boundary condition change in a construction stage; s2, analyzing the anti-seismic performance of the steel reinforced concrete frame structure in the construction process by adopting a time-history analysis method, wherein the time-history analysis is based on a seismic wave acceleration time-history curve; s3, according to the time history analysis result, determining an earthquake response change rule of the steel reinforced concrete frame structure in the construction process; and S4, according to the earthquake response change rule, a measure for improving the anti-seismic safety of the steel reinforced concrete frame structure in the construction process is determined.

The invention discloses a composite mineral admixture prepared from heat-stewed steel slag and a preparation method of the composite mineral admixture, and the mineral admixture is prepared from the following raw materials in parts by weight: 40-50 parts of heat-stewed steel slag powder, 20-30 parts of granulated blast furnace slag powder, 20-40 parts of fly ash, 0.01-0.1 part of a grinding aid and 0.5-4.0 parts of an exciting agent, wherein the grinding aid comprises glycerol and diethanol isopropanolamine, and the exciting agent comprises diphenyl phosphate, sodium sulfate and ammonium bicarbonate. The preparation method comprises the following steps: mixing calcium bicarbonate and water, spraying the mixture on high-temperature steel slag at 600-800 DEG C, carrying out hot braising under the condition of steam pressure of 0.2-0.5 MPa for 8-12 hours to pulverize the steel slag until the particle size is less than 5-10 mm, and carrying out vertical milling on the pulverized steel slag and a grinding aid for 20-40 minutes to obtain hot-braised steel slag powder; uniformly mixing the heat-stewed steel slag powder, granulated blast-furnace slag powder, fly ash, a grinding aid and an exciting agent in proportion to obtain mixed powder; and finally, grinding the mixed powder for 30-50 minutes by adopting a high-energy planetary ball mill to obtain the cement concrete composite mineral admixture with the specific surface area being greater than or equal to 600m < 2 > / kg. According to the invention, the potential hazard of poor stability of a cement concrete material caused by high f-MgO content in the steel slag is broken through, the steel slag is efficiently utilized to prepare a low-carbon green building material, a composite mineral admixture is developed, and the performance meets the II type requirement in JG / T 486-2015 Composite Admixture for Concrete.

The invention discloses a UHPC (Ultra High Performance Concrete) formwork-removal-free combined node linear coupling beam shear wall and a construction process thereof. The UHPC formwork-removal-free combined node linear coupling beam shear wall comprises a post-cast reinforced concrete shear wall, a UHPC formwork-removal-free, a laminated slab, a concrete-filled steel tube positioning bolt and a shear wall embedded column, the UHPC non-dismantling formwork comprises a non-perforated formwork body and a perforated formwork body, perforated steel plates are evenly pre-buried in the inner side of the non-perforated formwork body and evenly pre-buried in the inner side of the perforated formwork body, round holes are reserved in the corresponding positions of the perforated steel plates, one side of a screw sequentially penetrates through the round holes of the perforated formwork body and the perforated steel plates, and the screw is arranged between the perforated formwork body and the non-perforated formwork body. The other side of the screw rod is preliminarily fixed through a first nut on the inner side of the non-perforated formwork, and U-shaped shear nails are arranged on the inner side of the non-perforated formwork and the inner side of the perforated formwork. According to the UHPC formwork-removal-free combined type node linear coupling beam shear wall and the construction process thereof, on-site quick assembly sealing and precise assembly are achieved, the formwork removal procedure is omitted, the assembly rate is increased, and the later maintenance cost is reduced.

The utility model relates to a prefabricated middle partition wall structure of a tunnel ventilation inclined shaft. The prefabricated middle partition wall structure at least comprises a bottom supporting structure, a steel supporting assembly and a prefabricated modular wallboard. A positioning groove is formed in the top face of the bottom supporting structure, and the bottom of the steel supporting assembly is embedded into the positioning groove and fixed. The prefabricated modular wallboard is formed by splicing a plurality of prefabricated slabs, the adjacent prefabricated slabs are connected through tongue-and-groove structures which are matched in a concave-convex mode, and the tongue-and-groove joints are filled with sealing materials. The steel supporting assemblies are longitudinally arranged at intervals, and the tops of the steel supporting assemblies are fixed to a tunnel lining to form a steel-concrete combined structure for supporting the prefabricated modular wallboard. The steel supporting assembly and the prefabricated modular wall plate form a steel-concrete prefabricated structure, and the stability of the whole structure is enhanced. By adopting the autoclaved aerated concrete precast block material and the concave-convex groove embedded modular structure, the problems that the construction quality is difficult to control, the construction period is long, the on-way resistance of air flow is large and the like in the existing reinforced concrete mid-partition wall are solved.

The present invention relates to the technical field of bridge engineering. Particularly disclosed are a steel shell-concrete composite orthotropic bridge deck structure and a fabrication method and device. The steel housing-concrete composite orthotropic bridge deck structure comprises a steel shell structure, infilled concrete, longitudinal and transverse stiffening ribs arranged at the bottom of the steel shell structure, and a deck-end connecting structure, wherein the steel shell structure comprises an upper steel plate and a lower steel plate that are arranged in parallel, and a plurality of perforated T-shaped ribs arranged in parallel in a longitudinal direction. Webs of the perforated T-shaped ribs are welded to the upper steel plate, flanges are riveted to the lower steel plate, the upper steel plate and the lower steel plate are connected into the steel shell structure, and reinforced concrete tenons formed by the perforated T-shaped ribs and core bar reinforcements and shear bolts anchor the upper steel plate and the lower steel plate in the infilled concrete to form a steel shell-concrete composite deck that bears loads jointly. The present invention provides high bending stiffness, solves the problem of fatigue at welds between the stiffening ribs and a steel top plate, fully utilizes the properties of a steel shell and concrete, and solves the problems of the crackability under a negative bending moment and excessive weight of a traditional composite bridge deck.

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.

The embodiment of the invention discloses a vibration control method and system for a steel-concrete combined box girder bridge, and the method comprises the steps: carrying out the vehicle-bridge coupling vibration analysis through building a space finite element model which accurately considers the interface slippage and shear hysteresis effect; an initial optimal parameter group of the multi-tuned mass damper is optimized and determined based on an analysis result, and installation tuning is carried out; in the operation stage of the bridge, vibration is monitored in real time through the sensor system, parameters of the damper are dynamically adjusted by the controller according to the deviation between measured data and a target value, and self-adaptive control is achieved. Thus, high-precision simulation, optimization design and intelligent control are combined, the problem that the control effect is poor due to model simplification and fixed parameters in a traditional method is solved, and vibration suppression accuracy and environmental adaptability are remarkably improved.

The invention discloses an improved DMO topological optimization method obeying different material yield criteria and analysis equipment, and belongs to the technical field of engineering structure optimizing.The method comprises the steps that a topological optimization mathematical model is established with the minimum flexibility as an objective function and stress constraints and cost constraints of different yield criteria as constraint functions; the interpolation of the DMO method based on the elastic tensor is rewritten into a unit superposition method to carry out unit discretization rigidity interpolation, and a plurality of stress values of each unit of each material can be calculated by using a separable stress interpolation scheme based on the unit superposition method; finite element analysis and stress calculation are carried out on the structure, von-Mises and Ducker-Prager yield criteria are given to steel and concrete materials respectively, and an MMA algorithm is used for iteratively calculating a result to obtain an approximate optimal solution; and circularly iteratively updating the unit density and the solving steps until the new topological optimization structure reaches a preset convergence condition. According to the method, topological optimization of the steel-concrete composite structure is more accurately carried out, and the obtained topological optimization result has manufacturability.

The invention discloses a composite beam plastic flexural capacity correction calculation method considering interface slippage. The method is suitable for a hogging moment area of a steel-concrete composite beam reinforced by an external prestress carbon fiber reinforced composite material rib. The method comprises the following steps: firstly, determining basic static boundary parameters and a shear connector constitutive model; in the iterative calculation, solving a temporary bearing capacity by utilizing an axial force and moment balance equation, and calculating interface slippage along the beam length and a deformation loss item at the support based on internal force distribution; then determining a rigidity degradation coefficient according to the average slip amount, and dynamically reducing the static yield bending moment to reconstruct the plastic hinge length; and finally, constructing a corrected deformation coordination equation, deducting a deformation loss item in geometric deformation calculation to obtain the real elongation of the in-vitro CFRP rib, and updating a stress parameter until a result is converged. According to the method, by introducing a deformation loss item and a rigidity degradation mechanism, deviation caused by traditional rigid connection assumption is corrected, and accurate prediction of the ultimate bearing capacity is achieved.

The invention relates to the technical field of simulation calculation, in particular to a simulation calculation method of a U-shaped steel-encased-concrete composite beam, which comprises the following steps: S1, establishing a two-parameter interface equivalent stiffness model of the U-shaped steel-encased-concrete composite beam with a rear anchor bolt; s2, solution and response extraction; s3, calculating a slip residual error and interface energy, and judging whether a target slip feature is met or not according to a double-convergence criterion; if the convergence requirement is not met, adaptively updating the interface parameters and returning to S2 for repeated solution, and if the convergence criterion is met, applying the converged interface rigidity parameters to design feedback of pretightening force selection of the rear anchor bolts and anchor bolt spacing and node construction of the rear anchor bolts. According to the method, the two-parameter interface equivalent stiffness model and the adaptive algorithm based on the slip residual error enable the interface normal stiffness and the interface tangential stiffness to be automatically converged to the target slip characteristic, manual parameter adjustment is avoided, the simulation stability and the calculation precision are improved, and integration of composite beam structure design and simulation analysis is achieved.

The invention belongs to the technical field of building materials, and discloses a concrete composite additive and a preparation method thereof. The additive comprises a polycarboxylate superplasticizer, nano silicon dioxide, modified starch ether, bentonite, a calcium sulphoaluminate activator, a bio-based antirust agent and a graphene oxide dispersion liquid. Through a step-by-step mixing process, liquid phase dispersion is performed firstly, then solid phase gradient mixing is performed, and ultrasonic treatment and low-temperature drying are combined, so that the problem of multi-component interface compatibility and activity retention is solved. The obtained additive can synergistically improve the anti-cracking and anti-rust performance of concrete, significantly reduce chloride ion penetration and prolong the durability period. And the preparation method is environment-friendly, efficient and suitable for high-durability concrete engineering.

The invention provides a splicing type steel-concrete composite structure. The splicing type steel-concrete composite structure comprises at least two beam sections and a splicing joint. The splicing joint is provided with a steel column and a first steel beam, the steel column is connected with the first steel beam in a welded mode, a widened flange plate is arranged on a first steel beam upper flange of the first steel beam, and a haunching plate is arranged on a first steel beam lower flange of the first steel beam. In the splicing joint area, the widened flange plates are arranged on the upper flanges of the steel beams, the haunching plates are arranged on the lower flanges of the steel beams, the flanges or webs of the whole steel beams do not need to be thickened, the bearing capacity of the steel beams can be effectively improved, and the overall earthquake load cannot be increased.

The invention belongs to the technical field of concrete, and particularly relates to a concrete composite material for roads and bridges and a preparation method thereof. The concrete comprises the following raw materials: a cementing material system, an aggregate system, a hybrid fiber system, a stable liquid storage lightweight aggregate and an additive system, the cement, the fly ash and the silica fume are used for constructing a cementing material system, the high-strength lightweight aggregate is sucked into the composite internal curing liquid and then is subjected to surface layer liquid stabilizing treatment to obtain the liquid stabilizing type liquid storage lightweight aggregate, and the internal humidity retention capacity and the early-age shrinkage state of the concrete are improved through synergistic cooperation of all the components in the composite internal curing liquid; the steel fiber and the PVA fiber are further combined to construct a multi-scale hybrid fiber reinforcement system, and PVA fiber surface activation treatment, staged water adding wet mixing and liquid stabilizing type liquid storage lightweight aggregate rear-section low-speed adding processes are adopted, so that the fiber dispersion uniformity is improved, the early liquid loss risk of the lightweight aggregate in the mixing stage is reduced, and comprehensive improvement is achieved.

This invention discloses a steel-concrete composite sleeper for ballastless track, belonging to the field of ballastless track technology. The steel-concrete composite sleeper includes multiple adjusting pipes and two spaced-apart sleeper units. Each sleeper unit includes multiple steel pipes and sleeper blocks. For any given sleeper unit, the multiple adjusting pipes and multiple steel pipes correspond one-to-one. One end of each steel pipe is inserted into a sleeper block, and each steel pipe is filled with concrete filler. Each sleeper block and the corresponding concrete filler are integrally cast with concrete. The other ends of two opposing steel pipes are movably and coaxially inserted into the two ends of the corresponding adjusting pipes to adjust the spacing between the two sleeper blocks. This invention provides a steel-concrete composite sleeper for ballastless track, which not only allows for the pre-casting of sleeper units, improving the overall construction efficiency of ballastless track, but also allows for adjustment of the track gauge between the two rails, ensuring the gauge meets on-site installation requirements.

The utility model discloses a formwork-free on-site assembly steel-concrete composite beam structure. The composite beam structure comprises two H-shaped steels, a steel beam and a steel beam, channel steel; two pieces of angle steel with opposite openings are arranged on the upper flange plates on the two sides of the channel steel; two folding flanges are arranged on the top face of the steel tank, and the transverse inner side faces of the folding flanges are connected to a lower flange plate of one piece of H-shaped steel; the bottom end of the long bolt rod is provided with a nut and embedded into concrete poured in the steel groove, the top end of the long bolt rod is upwards fastened, the upper flange plate and the transverse plate of the angle steel are connected in an overlapped mode, and the top end of the long bolt rod is provided with a nut and embedded into concrete poured in a groove cavity formed between the angle steel. According to the steel-concrete composite beam structure, the steel-concrete composite beam can be directly assembled on site through hot-rolled section steel products, the steel structure machining and manufacturing links are avoided, welding, formwork installation and reinforcing steel bar binding operation are not needed, the technological process is greatly shortened, independent replacement of a single component can be achieved in the operation period, and economic benefits are remarkable.

The utility model relates to a support-free recyclable steel-wood combined truss laminated slab. The laminated slab is composed of a prefabricated slab, in-slab steel bars, a steel-wood combined truss and a laminated layer. The prefabricated plate is located at the bottom, the in-plate steel bars and the steel-wood combined truss are sequentially arranged above the prefabricated plate, and the laminated layer is poured above the prefabricated plate. Lower chords and web members of the steel-wood combined truss are made of steel bars, upper chords are made of battens, and the bottom faces of the battens are higher than the top face of the concrete-poured laminated layer by a certain distance, so that disassembly is convenient. The bending resistance of the steel-wood combined section is utilized, an under-plate support is omitted, the leasing cost of the scaffold is saved, the wood beams can be repeatedly utilized, and remarkable economic and social benefits are achieved.

The utility model relates to an inserting column end bearing type column base node which comprises a steel pipe concrete column, the steel pipe concrete column is composed of a steel pipe core column, peripheral reinforced concrete, a bottom plate and a bottom wrapping steel plate, the steel pipe core column extends downwards from the bottom face of the peripheral reinforced concrete, and the bottom plate is annularly welded to the periphery of the steel pipe core column on the bottom face of the peripheral reinforced concrete. The bottom wrapping steel plate wraps the periphery of the bottom of the peripheral reinforced concrete, a plurality of first stiffening ribs are welded to each side of the bottom wrapping steel plate and connected with the steel pipe core column in a welded mode, and the bottom plate extends outwards in the radial direction from the bottom wrapping steel plate. And a cup opening is reserved in the column foot foundation, and a plurality of groups of anchor bolts are pre-buried around the cup opening. The end of the concrete filled steel tubular column is supported on the top of the column foot foundation, the structure is simple, the anti-seismic performance is excellent, the quality is reliable, the construction speed is high, and the node construction method is high in cost performance.

The utility model provides a steel-concrete composite beam cast-in-place bridge deck slab supporting structure which comprises a plurality of steel plate beams with the two ends supported on bridge piers, a plurality of pairs of hanging rings are arranged between the adjacent steel plate beams, two hanging rings in one pair of hanging rings are prefabricated on the edges of the two steel plate beams respectively, and the hanging rings extend in the extending direction of the steel plate beams. The lifting rings at the same end are arranged at the two ends of the middle main beam in a sleeving mode, a plurality of middle transverse distribution beams are laid on the main beam, the steel plate beam comprises a top plate, a bottom plate and a vertical plate connecting the bottom plate and the top plate together, and middle supporting pads are laid on the middle transverse distribution beams. The steel plate beam and the middle supporting pad form a bridge deck slab bottom formwork. The utility model has the advantage that the construction of the cast-in-place bridge deck of the steel-concrete composite beam can be completed without erecting a support frame on site, and solves the problem that the existing cast-in-place bridge deck of the steel-concrete composite beam needs to erect a support structure supported on the ground on site for construction.

This invention discloses a crack-resistant rheologically modified functional material for steel-concrete composite cable towers, its preparation method, and its application. The crack-resistant rheologically modified functional material of this invention comprises 1-10 μm ultrafine light-burned magnesia expandable material, 15-30 μm medium-fine light-burned magnesia expandable material, 30-100 μm medium-coarse calcareous expandable material, 0.1-2 μm fly ash microspheres, 0.02-0.05 μm nano-silica, and an anti-agglomeration regulating material. The anti-agglomeration regulating material is composed of a zirconium aluminate coupling agent and hexadecyltrimethylammonium bromide. This crack-resistant rheologically modified functional material is applied to the concrete of ultra-high strength steel-concrete composite cable tower structures. Concrete prepared using the crack-resistant rheologically modified functional material of this invention exhibits low viscosity, good anti-segregation properties, and volume stability, achieving a synergistic unity of rheological modification and crack-resistant expansion in the concrete of ultra-high strength steel-concrete composite cable tower structures.

The application discloses a type steel beam shear wall system which is easy to process, assemble, decorate and bear stress, and relates to the technical field of building engineering, and comprises the following steps: hollow type steel beam framework, which comprises at least three type steel columns arranged at intervals along the same horizontal direction and a plurality of inter-column plates arranged at intervals along the radial direction of the type steel columns; and plain concrete, which covers the hollow type steel beam framework, wherein the thickness of the plain concrete on the outer side of the framework is 20-50 mm; and the two ends of the type steel column respectively extend out of the outer part of the plain concrete to form anchoring sections. The application solves the problems of the existing building engineering, such as poor stress system, non-dense sleeve grouting at the connecting part, insufficient node stress and seismic performance, the need of fireproof paint in the steel-concrete composite structure system, long construction period, high cost and difficulty in decoration.

This utility model relates to the field of construction, specifically a steel plate connection structure for primary and secondary beams. The secondary steel-concrete composite beams are symmetrically arranged on both sides of the primary steel-concrete composite beam, forming a cross-shaped arrangement. The primary steel-concrete composite beam is horizontally fitted with upper and lower flange connecting plates, corresponding to the heights of the upper and lower pipe walls of the secondary steel-concrete composite beams, respectively. The two end faces of the upper and lower flange connecting plates support the upper and lower pipe walls of the secondary steel-concrete composite beams from bottom to top. This utility model significantly improves the construction efficiency of connecting primary and secondary beams and has a simple structure.

1. Name of the designed product: concrete composite slab. 2. Use of the designed product: floor slab for construction engineering. 3. Design points of the designed product: in shape. 4. Picture or photo best indicating the design points: design 1, perspective view 1. 5. Design 1 is designated as the basic design.

The invention discloses an anti-crack rheology modified functional material for a steel plate-concrete combined cable bent tower as well as a preparation method and application of the anti-crack rheology modified functional material. The anti-crack rheological modified functional material comprises a 1-10 [mu] m superfine light-burned magnesia expansion material, a 15-30 [mu] m medium-fine light-burned magnesia expansion material, a 30-100 [mu] m medium-coarse calcium expansion material, 0.1-2 [mu] m fly ash microspheres, 0.02-0.05 [mu] m nano-silica and an anti-agglomeration regulation and control material, wherein the anti-agglomeration regulation and control material is formed by compounding a zirconium aluminate coupling agent and cetyltrimethylammonium bromide; the anti-crack rheological modified functional material is applied to ultrahigh-strength steel plate-concrete combined cable bent tower structure concrete. The concrete prepared from the anti-crack rheology modified functional material prepared by the preparation method has low viscosity, good segregation resistance and volume stability, and the synergism and unification of concrete rheology modification and anti-crack expansion of an ultrahigh-strength steel plate-concrete combined cable bent tower structure are realized.

The embodiment of the invention discloses a multi-stage collaborative supporting method and structure for an ultra-deep well large-span chamber, and the method comprises the following steps: firstly identifying an overlying key rock stratum and calculating a pressure relief range, carrying out'skylight opening 'excavation on the overlying key rock stratum of the large-span chamber to realize high stress transfer and pressure relief, and releasing pressure for the large-span chamber to be excavated. The cavern is in a low-stress state, and dynamic disasters such as rock burst and the like caused by cavern stress concentration or high-stress cavern large-deformation disasters are reduced; precise excavation is carried out to form a chamber, first-time supporting is carried out, high-pretightening-force yielding anchor cables are applied to a top plate and side parts, and a deep and shallow part cooperative bearing layer is formed through long anchor cables and short anchor cables; and then secondary supporting is carried out, loosening blasting pressure relief is carried out on the base angles, a high-strength concrete-filled steel tube support is erected, and the space between the high-strength concrete-filled steel tube support and the surrounding rock is filled with a yielding back plate. And then grouting anchor cables are constructed at the bottom corners to block stress transfer, and pressure relief drill holes are constructed in the top slope part to regulate and control the surrounding rock stress. And finally, an anti-slide pile is vertically arranged in the center of the bottom plate.

The invention discloses an inorganic nanofiber reinforced concrete composite material for a lightweight building material, and relates to the technical field of advanced inorganic non-metallic materials, the composite material is prepared from cement, lightweight aggregate, fine aggregate, modified inorganic nanofiber, a mineral admixture, a water reducer, a dispersant and water, the modified inorganic nanofibers are subjected to surface activation treatment through a silane coupling agent, the interface bonding strength with a cement matrix is improved, the preparation method comprises the steps of nanofiber surface modification, ultrasonic dispersion, dry material mixing, wet material stirring, aggregate adding and forming and curing, the dry apparent density of the prepared composite material is 1400-1600 kg / m < 3 >, the 28-day compressive strength reaches 35-45 MPa, and the composite material is suitable for being used as a cement-based composite material. The light-weight high-strength light-weight building material has the characteristics of light weight, high strength, good crack resistance and excellent durability, and is suitable for the fields of novel wall materials and light-weight building materials.

This invention discloses a multi-layered internal structure for shield tunneling based on a steel-concrete composite structure, including a flue slab, an upper lane slab, and a lower lane slab. The flue frame structure of the flue slab is connected to the steel plates pre-embedded in the corresponding tunnel segments, and the edges of the corresponding steel-concrete composite slab are sealed to the corresponding tunnel segments by cast-in-place concrete. The upper lane frame structure of the upper lane slab is fixed to the steel plates pre-embedded in the corresponding tunnel segments by multiple upper lane steel brackets. The lower lane slab has precast components at the bottom of the tunnel, with steel-concrete composite slabs on both sides, and the outer sides of the steel-concrete composite slabs are supported on steel longitudinal beams. The steel longitudinal beams are fixed to the steel plates pre-embedded in the corresponding tunnel segments by multiple lower lane steel brackets. During construction, the lower lane slab, upper lane slab, and flue slab are constructed sequentially from bottom to top, and finally the asphalt pavement layer is laid. The application of this invention reduces the self-weight, eliminates the need for rebar installation in tunnel segments, improves structural reliability and construction efficiency, and also frees up internal space in the tunnel.

The invention discloses a modular assembly type aluminum alloy-concrete composite shear wall structure and a bending bearing capacity calculation method thereof, and belongs to the technical field of building structures. In order to solve the problems that an existing double-steel-plate-concrete composite shear wall has many welding defects, steel plates are prone to rusting, the operation and maintenance cost is high, and the construction efficiency is low, an aluminum alloy material is adopted for replacing steel, an integrally-formed aluminum alloy wall plate and a modular opposite-pull connecting system are designed, and the solid-phase friction stir welding technology with low heat input is combined; the combined shear wall with the characteristics of light weight, high strength, corrosion resistance and convenience in construction is formed, and an accurate bending bearing capacity calculation method is provided. The structure can improve the construction efficiency and reduce the operation and maintenance cost, is suitable for super high-rise buildings, special environment buildings and structures and other scenes, and has remarkable engineering application value.

This invention relates to the technical field of prefabricated steel structures, specifically to a connection structure and method for prefabricated steel-concrete composite bridge piers. The outer wall of the central tube is provided with multiple ribs distributed circumferentially around it. The length of the ribs matches the length of the central tube and extends along the generatrix of the central tube. Positioning rings are located on the outer wall of the ribs, forming two corresponding steel tube connectors. These connectors are inserted into the two steel tubes, connecting them as a whole. Two expansion ends are located at both ends of the central tube and connected by tie rods. Pulling the two expansion ends causes the central tube to expand circumferentially, thereby pressing the ribs tightly against the inner wall of the steel tube. Through the tie rods and the frustoconical expansion ends, uniform circumferential expansion of the central tube can be achieved, resulting in a tight fit between the ribs and the inner wall of the steel tube. This provides self-adaptive fastening throughout the connection, uniform stress distribution, no localized stress concentration, and high joint strength and stability.

The invention relates to the technical field of steel-concrete composite beam installation, in particular to a control device and method for segmented installation of a river-crossing steel-concrete composite beam. The control device comprises a hoisting system and an adjusting tool composed of a shaping square frame, a combined keel and a positioning frame; the four end corner positions of the square fence are each provided with a movable support in a sliding mode, crawler wheels are arranged at the lower ends of the four movable supports, and the balance adjuster comprises a lever traction assembly used for pulling the two movable supports on the same side to vertically ascend and descend so as to keep the front and back of the square fence flush. The adjusting tool is designed to be a detachable shaping square frame, a keel and a positioning frame module are combined, segmented hoisting and on-site assembly are achieved in combination with a hoisting system, and the vertical height and the inclined supporting angle of the movable support can be monitored in real time and automatically adjusted; the combined keel is hoisted through a second hoisting device; and the splicing process is beneficial to reducing manual adjustment operation and shortening the construction period.