741 results about "Composite beams" patented technology

The invention provides an ultra-short beam homogenization transmission line system and method based on a four-eight-pole composite magnet. The system comprises the four-eight-pole composite magnet, a system, a linear beam homogenization structure, a bent beam homogenization structure and secondary iron used for a beam homogenization transmission line. The system further comprises an ultra-short linear beam homogenization transport line, an ultra-short bent beam homogenization transport line, an ultra-short linear bent composite beam homogenization transport line and an ultra-short symmetrical bent beam homogenization transport line based on the homogenization structure and / or the dipolar iron. The method comprises an exciting current debugging method based on the four-pole and eight-pole composite iron and a linear type and bending type beam debugging method. According to the invention, the problem that the maximum enveloping part on the transmission line is occupied and the effect of octopole iron cannot be fully exerted is solved; the problems that the beam envelope of the position where the octopole iron is located is small, and the requirement for the field intensity of the octopole magnet is high are solved. The problem that the civil engineering shielded around the transmission line is more expensive because the transmission line is too long is solved.

The invention relates to the technical field of building structures, in particular to a method for calculating node shear bearing capacity of a composite beam, which comprises the following steps of: decomposing the shear bearing capacity of a node core area into shear contribution components of a square steel tube web, encased concrete and a steel wire mesh, and respectively calculating the shear bearing capacity based on respective structural characteristics and stress mechanisms; the total shear bearing capacity is obtained through superposition; and each component is quantized by introducing correction coefficients of an axial compression ratio and a beam-column linear stiffness ratio. According to the method, the technical blank of shear resistance calculation of the concrete joint in the core-free area is filled, the error is controlled within + / -15%, and the method has the characteristic of high precision, is suitable for design of the composite beam joint filled with the concrete in the core-free area in a high-rise building and an underground structure, is high in engineering applicability and provides a reliable calculation basis for design of related building structures.

The invention relates to the technical field of structural engineering, and discloses a post-fatigue residual stiffness calculation method for an assembly type composite beam, which comprises the following steps: acquiring three-dimensional laser point cloud data and thermal infrared image data of the composite beam, and registering the three-dimensional laser point cloud data and the thermal infrared image data; quantifying the macroscopic geometric defect based on the multi-modal data; welding area features are extracted, and micro-crack forms are recognized; constructing a microcrack network diagram and extracting parameters; evaluating the influence of the microcrack network on the local rigidity by adopting a self-attention map neural network, and obtaining a rigidity parameter after multi-scale damage correction in combination with the influence of the macroscopic geometric defect; calculating residual stiffness after fatigue by combining fatigue load history; according to the method, the initial geometric defect and the early microscopic damage can be comprehensively considered, and the accuracy of the residual stiffness calculation of the fabricated composite beam is improved.

A composite wall and building system. The composite wall and building system provide a structural beam formed of fiberglass composite having one or more flanges that engage with an insulation member. The structural beam may be formed in a variety of dimensions and profiles. A plurality of structural beams is used together to form a wall or other parts of the building. A panel is used to cover the beams and insulation. The wall sections are joined together with interlocking beams and fasteners are used to secure the beams to each other and wall sections to other wall sections. The composite beams and insulation are coated with a fire-retardant material. A modified beam is used in certain applications for additional strength and connection points with other preexisting wood structures.

The invention discloses a corrugated steel web I-shaped section and a manufacturing method of a steel box composite beam, and relates to the technical field of steel box composite beams. The rod piece web I-shaped piece is installed on the side face of the bottom plate unit; the partition plate type web I-shaped pieces are installed on the side faces of the bottom plate units, and the partition plate type web I-shaped pieces are connected with the rod piece web I-shaped pieces; the solid-web type partition plate units are installed on the bottom plate units, and the solid-web type partition plate units are arranged between the partition plate type web I-shaped pieces; the truss type partition plate units are installed on the bottom plate units, and the truss type partition plate units are arranged between the rod piece web I-shaped pieces. The manufacturing method of the steel box composite beam comprises the steps that the bottom plate units, the web I-shaped pieces and the partition plate units are transported to a site to be erected, assembled and welded. The technical problem that in the prior art, a concrete bottom plate and corrugated steel web structure cannot meet the requirement for a large-span bridge is solved.

The invention provides a large-span corrugated steel web composite beam and a construction method thereof. The composite beam adopts section prefabrication and field assembly, and a composite abutted seam system is creatively adopted between beam sections. Butt welding is adopted for corrugated steel webs between beam sections, glue seams are adopted for concrete, and shear key teeth are matched, so that the self-alignment performance and the interface shear bearing capacity of a matching surface are improved; wave-shaped abutted seam notches are formed in the upper portions of the concrete top plate and the concrete bottom plate, concrete above abutted seams is a continuous pouring body, the waterproof performance is durable and reliable, and the long-term safety and the service life of the structure are effectively guaranteed under the condition that a waterproof leveling layer is not arranged. And in addition, the concrete in the notches is pre-pressed through the tensioning external prestressing procedure after the beam bodies are closed, the concrete at the abutted seams is further compacted, and super-strong durability is provided. A concrete waterproof layer does not need to be independently arranged on the main beam structure, the second-phase dead load borne by the main beam is effectively reduced while the work amount is reduced, and economic benefits are remarkable.

The invention discloses a terahertz wave band composite beam RF MEMS switch with low driving voltage, and belongs to the field of radio frequency front-end devices. The device is composed of a direct current port metal block, a direct current bias line, a microstrip line matching structure, a composite beam MEMS switch, a composite beam middle conduction structure, a metal electrode of a composite beam, a silicon nitride insulating layer, a quartz glass substrate, a coplanar waveguide metal ground and a metal ground. The composite beam MEMS switch is formed by combining a silicon dioxide material clamped beam and a metal beam adsorbed below the silicon dioxide material clamped beam, a direct current port is connected to the anchor point position of the metal beam and a metal electrode through a direct current bias line, and different direct current voltages can be input through the direct current port to control the lifting state of the composite beam and the pull-down state of the composite beam adsorbed to the electrode. The two switches respectively correspond to an off state and an on state of the switch. The composite beam MEMS switch works below 140GHz, so that low driving voltage, low insertion loss and high isolation are realized. The reaction time of microsecond magnitude is achieved, destructive deformation is not prone to occurring, the structure is simple, and manufacturing is easy.

The utility model provides an inter-beam connecting structure for a steel and concrete composite beam, which comprises a composite beam, the composite beam comprises a bridge deck slab and a composite rib plate positioned on the bottom surface of the bridge deck slab, the butt joint end of the bridge deck slab is provided with a first bridge deck post-pouring area, and the butt joint end face of the bridge deck slab is provided with a connecting plate II in the range of the first bridge deck post-pouring area; the second connecting plates of every two adjacent composite beams are connected through second bolt assemblies, and after connection is completed, UHPC concrete is poured into the first bridge floor post-pouring area; the combined rib plates of every two adjacent combined beams are connected in a rigid connection mode. The two second connecting plates are connected through bolts, concrete is poured into the first bridge deck post-pouring area after bolt connection, the connecting integrity between the bridge deck slabs is good, and meanwhile the situation that heat is generated by welding between the second connecting plates, and connection between the second connecting plates and the bridge deck slabs is affected is avoided.

The invention discloses a steel-UHPC (Ultra High Performance Concrete) combined bridge deck slab composite beam segment total assembly automatic welding method, which relates to the technical field of bridge construction in fixed buildings, and comprises the following steps: S1, positioning a central flat bottom plate unit, fixing the central flat bottom plate unit with a jig frame, then positioning and assembling flat bottom plate units on two sides, and finally assembling an inclined bottom plate unit to form a bottom plate unit; s2, assembling a middle partition plate unit on the bottom plate unit, temporarily supporting the middle partition plate unit, then positioning a middle web plate unit, and finally welding the middle web plate unit, the middle partition plate unit and the bottom plate unit; s3, the side partition plate units and the side web plate units are sequentially spliced on the inclined bottom plate units, and then the side partition plate units, the side web plate units and the inclined bottom plate units are welded; s4, the side top plate units and the anchor web plate units are positioned and welded; and S5, bridge deck prefabricated slabs are assembled, and then positioning, welding and fixing are conducted. The invention further discloses the technical problems that the labor intensity is high and the quality stability is poor during production of the steel-UHPC composite bridge deck slab composite beam.

The invention relates to the technical field of batteries, and discloses a composite beam, a battery pack lower shell and a battery pack. The composite beam comprises a main material made of a composite material and an auxiliary material made of a metal material. The main material is provided with at least one first cavity, and the first cavity penetrates through the main material in the length direction of the main material; the composite material is arranged in the first cavity, and the auxiliary material is fixedly connected with the main material. The composite material beam provided by the invention comprises the main material and the auxiliary material, the mode of combining the composite material and metal is adopted, the composite material beam not only has the advantages of light weight, low cost, high stability, good insulativity and good corrosion resistance of the composite material, but also has the strength of the metal material due to the fact that the auxiliary material made of the metal material is arranged in the first cavity of the main material; and the auxiliary material can make up the weft-wise strength of the pure composite beam, so that the composite beam has better comprehensive performance, and the product has higher competitiveness.

The invention relates to the technical field of building construction, in particular to an auxiliary scaffold for building a concrete filled steel tubular column and a composite beam, which comprises a support body consisting of a bearing screw rod inserted into the ground, a vertical rod mounted at the top end of the bearing screw rod in a threaded manner, a disc buckle fixed on the outer surface of the vertical rod and a bottom horizontal tube mounted on the disc buckle in a clamping manner, the number of the frame bodies is multiple, the multiple frame bodies are distributed at equal intervals and connected to form the scaffold, and leveling plates are arranged outside the bearing screws. A connecting mechanism is arranged above the leveling plate, the connecting mechanism comprises a base, a bearing seat and a locking piece which are sequentially distributed from bottom to top, and a horizontal connecting plate is hinged to the outer portion of the base. According to the auxiliary scaffold for building the concrete filled steel tubular column and the composite beam, the rotating locking piece moves downwards along with the bearing screw rod, the functions of unfolding the working platform and holding and locking the bearing screw rod can be synchronously completed, multiple construction steps are combined, and the building efficiency is greatly improved.

The invention discloses a steel-concrete composite beam structure assembled by hot-rolled section steel and a construction method of the steel-concrete composite beam structure. The composite beam structure comprises two pieces of H-shaped section steel; 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 and the construction method thereof, the steel-concrete composite beam can be formed by directly assembling the hot-rolled section steel products on site, the steel structure machining and manufacturing links are avoided, welding, formwork installation and 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 invention relates to a space curve prestress composite beam column and a design method thereof. The bottom of the space curve composite beam column is vertically upward, the tail end overhanging part is approximately horizontal, and the middle part is connected with the horizontal prestressed concrete closed beam to form a space structure. The horizontal closed prestressed beam and the space curve composite beam column support each other, the constraint boundary condition of the space curve composite beam column is changed, and the internal force distribution and magnitude of the space curve composite beam column are changed. According to the space curve composite beam column with the horizontal closed prestressed beam, the anti-cracking and anti-bending performance of a component is improved, and the deformation performance of the component is also improved. Therefore, the structure is particularly suitable for large cantilever structures with high deformation and bearing capacity.

The invention discloses a frame column and superposed beam connecting joint and a construction method thereof. The novel connecting joint mainly comprises a superposed beam, a frame column, a connecting cover plate and a post-pouring part. The frame column comprises a steel pipe column and a steel pipe concrete column, the composite beam is placed on a lower connecting ring plate of the steel pipe column, a composite beam bottom embedded steel plate is connected with the column lower connecting ring plate in a welded mode, and a composite beam top embedded steel plate is connected with a steel column upper connecting ring plate or a steel column wall plate in a welded mode through a connecting cover plate. And concrete, ultra-high performance concrete or grouting materials are poured into gaps between the superposed beam ends and the steel columns to form a whole. Compared with the prior art, reliable force transmission of the beam top rib and the bottom rib in a joint area is achieved through welded connection of the superposed beam embedded steel plate and the frame column, machining and construction links such as steel pipe column wall trepanning, reinforcement and beam top rib penetrating are effectively reduced, the technology is simplified, and efficiency is improved. The connecting joint of the frame column and the superposed beam is clear in force transmission path, simple in structure and convenient to construct, and has performance and construction advantages.

The invention discloses a variable cross-section continuous composite beam bending moment and displacement calculation method. The method comprises the following steps: S1, segmenting a variable cross-section continuous composite beam structure; s2, calculating anti-bending inertia moments of combined sections of different beam sections, and segmenting the variable-section continuous combined beam according to the anti-bending inertia moments of the sections to obtain a segmented uniform-section model; s3, geometric morphology equivalence is conducted on the variable-cross-section continuous composite beam according to a segmented uniform-cross-section model, half span is selected through symmetry to conduct theoretical analysis calculation, and the bending moment Mr at the segment point of the equivalent model section is obtained; s4, determining an actual inflection point position, and according to the actual inflection point position, performing further equivalent segmentation on the variable cross-section continuous composite beam; and S5, dividing the half-span variable cross-section continuous composite beam into three sections according to the positions of the cross-section segmentation points and the actual inflection points, establishing an equation based on the stress balance and deformation coordination relationship of the cross-section segmentation points and the actual inflection points, and providing a typical cross-section displacement, corner and bending moment calculation method.

The invention discloses a composite beam capable of enhancing the ultimate strength of an ultimate concrete structure. The span of the beam is measured, a bending moment graph of the beam is drawn, according to analysis of the bending moment graph, UHPC is selected for a pure bending section (the middle of the span) above a neutral axis of the beam, the upper half part of the beam is covered, and common concrete is used for the rest parts; half of the beam height is selected to use UHPC on the upper portion, and the structural ultimate strength of the composite beam can be improved; the FRP rib is used on the lower portion of the beam, the tensile property and ductility of the lower portion can be improved, a sleeve grouting anchorage device (the inner wall of a metal sleeve is provided with threads) and a wedge-shaped anchorage device (the clamping section is wrapped with a copper sleeve) are adopted, the anchoring reliability is ensured through the double effects of chemical bonding and mechanical meshing, and due to the fact that the FRP rib can be subjected to brittle failure and is preset to be in a super rib failure mode, the tensile strength and ductility of the lower portion can be improved. The problem of brittle failure of the FRP rib is solved. The beam is simple in design, convenient to construct, reasonable in stress, high in structural ultimate strength, high in reliability, wide in application range and material-saving.

The invention discloses a steel-concrete laminated slab composite beam structure and an assembly method, the structure comprises a steel plate shear connector, the left side and the right side of the steel plate shear connector are symmetrically provided with a group of concrete prefabricated bottom plates respectively, and a concrete post-pouring layer is arranged above the concrete prefabricated bottom plates; a plurality of clamping grooves are formed in the upper end of the steel plate shear connector, transverse additional steel bars are clamped in the clamping grooves, and the transverse additional steel bars extend to the left side and the right side to the position below the concrete post-pouring layer; each concrete prefabricated bottom plate comprises a middle plate and end plates located at the front end and the rear end of the middle plate, the upper surface of each middle plate and the upper surface of each end plate are each provided with a plurality of dovetail grooves in the front-back direction, and a plurality of seam splicing steel bars are jointly connected into the coaxial dovetail grooves in a clamped mode. The structure solves the problem that a traditional steel-concrete composite beam anti-shear connecting piece is limited in anti-shear performance; the prefabricated bottom plate is low in production efficiency and difficult to hoist and transport; during construction of plate end and plate side connecting structures, horizontal reinforcing steel bars conflict, and transverse additional reinforcing steel bars and abutted seam reinforcing steel bars are difficult to position.

The invention belongs to the field of deep foundation pit intelligent supporting systems, and particularly relates to a deep foundation pit intelligent supporting system based on oblique beam grid and digital twinning and a collaborative construction method.The deep foundation pit intelligent supporting system based on oblique beam grid and digital twinning comprises an oblique beam grid supporting structure composed of two-way crossed steel oblique beams, and the outer layer of each steel oblique beam is a Q355B steel pipe with the thickness not smaller than 12 mm; the inclined beam is filled with ultra-high performance concrete with the compressive strength not smaller than 150 MPa, the inclination angle of the inclined beam ranges from 25 degrees to 60 degrees, and an MEMS micro-electro-mechanical system sensor is pre-buried at a node; and the digital twin platform integrates the geological BIM model and the LSTM neural network prediction model. The bending rigidity is improved through the oblique beam grid supporting structure and the concrete filled steel tube composite beam, the inclination angle ranges from 25 degrees to 60 degrees, force flow transmission is optimized, and micro-strain-level stress monitoring is achieved through the MEMS sensors embedded in the nodes. A digital twin platform and an LSTM model are fused with 12-dimensional parameters, the 72-hour deformation prediction error is smaller than or equal to 1.5 mm, and compared with a traditional experience algorithm, the precision is improved.

A joint connect assembly may include a metallic ring connector configured to couple with one or more tubular composite beams. The joint connect assembly may include a layer arranged between the metallic ring connector and an external surface of the one or more tubular composite beams. The layer may be formed of a material configured to reduce local stress concentrations on the one or more tubular composite beams. The material of the layer may be an elastomeric material, e.g., the layer may include at least one of a natural rubber, synthetic rubber, or a combination thereof.

A composite support beam may be hollow, where the composite support beam includes an external fiber-reinforced polymer-matrix shell and one or more pultruded fiber-reinforced polymer-matrix composite parts. One or more walls of the external shell may define an internal cavity. The one or more pultruded parts may be arranged within the internal cavity defined by the one or more walls of the external shell. The one or more pultruded parts may be formed by a plurality of unidirectionally reinforced composites positioned in an axial direction of a respective hollow composite support beam. In some instances, the composite support beam may include an internal fiber-reinforced polymer-matrix shell.

The invention discloses a method for calculating the natural vibration frequency of a steel-concrete composite beam under common boundary conditions, and relates to the technical field of high-speed railway bridge construction. The method comprises the steps that material parameters and the cross sectional area of the steel-concrete composite beam are obtained; calculating a dimensionless coefficient according to material parameters and section parameters of the steel-concrete composite beam; according to the dimensionless coefficient, the first frequency reduction coefficient, the bending resistance combination connection coefficient, the second frequency reduction coefficient and the third frequency reduction coefficient; and calculating the natural vibration frequency of the single-span steel-concrete composite beam under the common boundary condition according to the three frequency reduction coefficient calculation expressions. According to the method, the shear deformation influence is considered, the frequency approximate value of the single-span steel-concrete composite beam under any boundary condition can be calculated, the calculation precision is high, and the method is also suitable for other partially-interacted composite beams formed by connecting two different materials through flexible shear connectors.

The invention discloses a prestressed composite beam structure and a mounting method, and relates to the technical field of bridge construction. The device comprises a bridge concrete abutment, a plurality of top beams are evenly and fixedly connected to the bottom of the bridge concrete abutment, supporting columns are symmetrically and fixedly connected to the bottoms of the top beams, triangular tables are fixedly connected to the opposite sides of every two adjacent supporting columns, and a prestressed concrete abutment is erected on the tops of the triangular tables. When the load received by the bridge concrete abutment is transmitted to the prestressed concrete abutment through the top beam and the diagonal bracing steel beam, part of the load borne by the prestressed concrete abutment is counteracted through tensioning of the prestressed tendons; and meanwhile, the stress rod is pushed to drive the supporting plate to convert partial load borne by the supporting beam into collision force between the supporting plate and the prestressed concrete base station, so that the load applied externally can be conveniently and effectively dispersed to the supporting columns, the prestressed tendons and the supporting plate for bearing, and the bearing stability of the device is effectively improved.

A method for laser welding a metal foil stack to a metal substrate includes clamping the foil stack against a support surface of a substrate and irradiating the stack with a beam of laser pulses to weld the foils to the substrate. The beam is a composite beam including a center beam and a surrounding annular beam. An initial series of the laser pulses are incident on the stack at mutually distinct locations on a top surface of the stack, and a subsequent series of the laser pulses are incident on the stack at mutually distinct locations on a side of the stack. The resulting weld nuggets penetrate deeply into the stack, with an average penetration depth that exceeds an average pitch between the weld nuggets. The method is capable of welding more than 100 foils to the substrate. Welded assemblies have been demonstrated to withstand large shear forces.

The invention relates to the technical field of bridge engineering, in particular to a linear control method for asynchronous construction of a PK section composite beam cable-stayed bridge, which is characterized in that in the manufacturing process, through pre-assembly and batch manufacturing, the manufacturing precision is accurately controlled, and the linear accuracy of a PK section composite beam section during manufacturing is ensured; in the transportation process, the manufacturing of the PK section composite beam section is reinforced, and the PK section composite beam section is prevented from being deformed by the supporting pad; in the hoisting process, it is ensured that the transverse line shape of the PK section composite beam section to be hoisted and the transverse line shape of the hoisted PK section composite beam section are consistent in a reverse jacking mode; in the subsequent construction process, the hoisting elevation positioning point is continuously measured, and even if the hoisting elevation positioning point deviates due to the rigidity change of the bridge, the longitudinal line shape can be adjusted by tensioning the stay cable.

The utility model provides an ultra-wide large-span composite beam bridge which comprises a foundation, two side piers, two middle piers and a steel concrete composite beam, the steel concrete composite beam is composed of a steel main beam, a UHPC bridge deck slab and concrete, and the steel main beam is erected on the side piers and the middle piers; the thickness of the UHPC bridge deck slab is 6-10 cm, the steel main beam comprises a closed steel box and a cantilever arm, a motor vehicle lane and a pedestrian and non-motor vehicle lane are arranged on the UHPC bridge deck slab, and steel beam bottom plates of the two middle piers are combined with concrete. The utility model provides an ultra-wide and large-span combined beam bridge which can be suitable for a highway-rail combined bridge with the span of more than 200m and the ultra-wide bridge width, the bridge width meets the requirements of two-way eight-lane and two-lane light rails, a pedestrian and non-motorized vehicle lane can be arranged, the utilization efficiency of the bridge is improved, and the beam bridge structure is more attractive; and the development of the ultra-wide and large-span composite beam bridge is promoted.

The invention provides a composite beam reliability optimization method based on a failure probability function. The method comprises the following steps: 1) defining a random input variable, a design variable, a target function and a performance function; 2) calculating a failure sample and an extended failure probability based on an autonomous learning Kriging agent model and a Monte Carlo method according to the Bayesian theory; the method comprises the steps of (1) calculating a design parameter failure sample, (2) calculating a joint probability density implicit function on the basis of an adaptive K-nearest neighbor method and autonomous learning Kriging according to the calculated design parameter failure sample, and (3) calculating a failure probability implicit function on the basis of the Bayesian theorem.By means of the method, the problem that in the reliability optimization process, the calculation cost is difficult to bear due to reliability analysis is solved.

The invention discloses a steel plate composite beam cable-stayed bridge tower beam consolidation connection structure which comprises a pressure-bearing steel plate, a concrete cushion block, a first connecting piece and a second connecting piece, the pressure-bearing steel plate is welded to the end of a steel main beam and is consolidated with the concrete cushion block through the first connecting piece, and the concrete cushion block and a concrete bridge tower are synchronously poured together. The concrete bridge deck slab is connected with the concrete bridge tower into a whole in a post-pouring mode, and the pressure-bearing steel plate and the concrete bridge tower are tightly connected together through the second connecting piece. The method has the advantages that the end pressure-bearing steel plates are adopted, axial force and bending moment are transmitted to the concrete bridge tower through the pressure-bearing steel plates, shearing force and torque are transmitted to the concrete bridge tower through connecting pieces of the pressure-bearing steel plates and friction force between the steel plates and the bridge tower, and the structural force transmission path is clear and simple; the pressure-bearing steel plates are provided with welding studs connected with the concrete cushion blocks, and conflict between the welding studs and concrete bridge tower main reinforcements is avoided; 3, the pressure-bearing steel plates are tightly connected with the concrete bridge tower through the opposite-pulling steel beams, so that insufficient shear capacity caused by small axial force of a main beam during construction is avoided, and meanwhile, the safety reserve of the structure during operation can be improved; the structure is simple, force transmission is reliable, and construction is simple.

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 bridge deck monitoring, and particularly discloses a wet joint monitoring system for a prefabricated bridge deck, a composite beam prefabricated member comprises a bottom shear nail, a top shear nail, a PBL perforated plate and a vertical trapezoidal key tooth wet joint, and the surface of the composite beam prefabricated member is brushed with white interior wall paint before a test is started; positioning grids are formed by using ink lines to serve as monitoring points, stress data and displacement data of the monitoring points on the surface of the composite beam prefabricated part are obtained and used for obtaining stress data and displacement data of the monitoring points on the surface after a load is applied, a change curve is drawn, damage variables are constructed according to the change curve, and recognition and early warning are conducted according to the damage variables. According to the method, high-precision and generalizable stress-deformation data can be obtained, and a solid foundation is laid for subsequent numerical simulation, health monitoring and remote maintenance.