106 results about "Prestressed concrete beam" patented technology

The invention discloses a nonlinear beam unit analysis method considering prestressed tendon bonding slippage, which comprises the following steps: establishing an overall structure analysis model according to the geometric dimension of a prestressed concrete beam, dividing calculation units, and assembling unit stiffness matrixes into a structural overall stiffness matrix; applying load and boundary conditions to the overall structure analysis model, and solving the overall analysis model by adopting a Newton iteration method; and extracting calculation results of structural deformation, stress, section internal force, prestressed tendon relative slippage and the like, drawing a load-deformation curve, and calculating structural rigidity and bearing capacity according to the slope and peak value of the curve. The calculation unit provided by the invention is an 8-degree-of-freedom beam unit, not only is the stress characteristic of the beam structure considered, but also the bond slip characteristic of the prestressed tendon is considered, the problem that a traditional beam unit analysis model cannot consider the bond slip effect of the prestressed tendon is solved, and compared with an entity unit analysis model, the convergence is better, and the calculation efficiency is higher.

The present invention discloses a method for constructing a large-volume, high-support prestressed concrete beam, which belongs to the technical field of prestressed beam construction. The construction preparation work includes presetting a full-length steel wire rope in a reserved channel for prestressed steel strands, installing a steel strand anchoring mechanism on the entrance side of the reserved channel, installing a limit plate on the exit side of the reserved channel, and presetting marks at the corresponding lengths of the steel strands extending from the movable pipe according to the length of the reserved channel; using the steel strand anchoring mechanism, multiple steel strands are synchronously pulled to the limit plate for cooperation, and the marks on the steel strands are adjusted to the same plane; the steel strands outside the reserved pipe near the anchor plate are cut, and a movable plate is installed, and the movable plates on both sides of the steel strands are tensioned to a preset elongation value; after tensioning is completed, grouting is performed in the reserved channel, and concrete is poured to form the beam body. The present invention can pipe multiple steel strands in the reserved channel as a whole, avoiding friction on the inner wall of the reserved channel and on the steel strands caused by pipe-lining individual steel strands.

The invention provides a novel large-span prestressed hybrid connection node segmental beam frame and a construction method. The frame comprises prefabricated columns, prefabricated assembled segmental beams, prestressed tendons, beam midspan steel bars and node connecting area steel bars. A prestressed tendon hole channel is reserved in the node area of the prefabricated column. An upper steel bar hole channel and a lower steel bar hole channel are pre-buried in the node area of the prefabricated column. The prefabricated assembly segmental beams are single-span prefabricated prestressed concrete beam segmental beams. The device is arranged at the beam bottom in the beam span, and generation and development of cracks in the beam span can be effectively controlled. A prestressed tendon bonding section with a certain length is arranged at the midspan position so as to prevent the steel strand from being integrally softened and losing efficacy in a fire disaster, and it can also be guaranteed that the beam midspan control section still has a certain bearing capacity once the prestressed tendon anchoring failure occurs at the beam end. And the beam end joint part can be poured by adopting fiber concrete or ECC concrete, so that the anti-cracking performance of the beam end is improved.

The utility model discloses a visualized adjusting device for the installation position of a corrugated pipe of a prestressed concrete beam, belongs to the technical field of building construction, and solves the problem that the installation position of a middle node of the corrugated pipe on an existing prestressed concrete beam structure is not accurate. The device comprises an I-shaped pipe fixed on an external prestressed concrete beam structure, a web pipe of the I-shaped pipe is sleeved with angle steel, external threads are arranged on the web pipe, and the web pipe is in threaded connection with two nuts located on the upper side and the lower side of the angle steel respectively; the angle steel is fixedly connected with a middle node of the corrugated pipe, and a scale steel bar is vertically arranged on the angle steel. The height of the mounting pipe is convenient to adjust, and the mounting position precision of the corrugated pipe is improved; the height of the angle steel is adjusted by adjusting the positions of the two nuts on the web pipe of the I-shaped pipe, so that the installation height of the corrugated pipe on the angle steel is convenient to adjust, and the installation position precision of the corrugated pipe is improved by observing scales on the scale steel bars.

The utility model discloses a prestressed duct grouting quality detection device, which is used for detecting the grouting quality in a prestressed duct of a prestressed concrete beam and comprises an impact echo device arranged in the length direction of the prestressed duct and a stress wave device arranged on the cross section of the prestressed duct, the data acquisition and analysis system is in signal connection with the impact echo device and the stress wave device; wherein the stress wave device is used for accurately determining an uncompacted area detected by the impact echo device. According to the prestressed duct grouting quality detection device, the duct grouting quality condition can be rapidly and effectively evaluated on the premise that the structure is not damaged, carrying and operation are convenient, the detection process is rapid, the construction progress is not affected, the detection result can be obtained in real time, and the potential damage risk to the structure and the duct is eliminated through a non-destructive detection mode.

The invention relates to the technical field of concrete beam stress testing, and provides a prestressed concrete beam stress testing method under wet-heat-force coupling, which comprises the following steps: S1, arranging a stress testing device, a temperature and humidity sensor and a strain gauge; s2, acquiring data of each sensor; s3, running a wet-heat-force coupling analysis fiber beam program; and S4, performing test-analysis collaborative correction. According to the method for testing the stress of the prestressed concrete beam under the wet-heat-force coupling, stress data are directly collected based on an embedded testing device of a plane section coordination principle, non-mechanical strain interference can be eliminated, an efficient fiber beam unit analysis and calculation method is constructed, a multi-module multi-field coupling fiber beam analysis program is integrated, and the method is suitable for large-scale popularization and application. According to the method, self shrinkage, drying shrinkage, intrinsic creep, drying creep, steel bar constraint and prestress relaxation effects are effectively considered, and the purposes of accurate identification of the true stress of the prestressed concrete beam and reliable evaluation of the structural performance in a complex environment are achieved.

The invention belongs to the technical field of civil engineering, and particularly relates to a prestressed tendon anchoring device suitable for various types of prestressed beams and an implementation method. Comprising a manufacturing pedestal, a prestressed concrete beam and an anchoring device, and the prestressed concrete beam is arranged on the manufacturing pedestal. The anchoring device comprises a supporting stand column, an anchorage device bearing platform, an anchorage device assembly and twisted steel, the supporting stand column is arranged at the end of the base, the anchorage device bearing platform is detachably connected to the supporting stand column, the anchorage device assembly is detachably connected with the anchorage device bearing platform, the twisted steel is installed on the anchorage device assembly, and one end of the twisted steel is connected with the prestressed concrete beam. The anchorage device bearing platform is arranged on the supporting stand columns, and the height of the anchorage device bearing platform can be adjusted according to needs. The device can be suitable for tensioning and anchoring reinforcing steel bars in various height, width and prestressed tendon arrangement modes, the production efficiency can be improved, and the cost can be reduced.

This utility model relates to a quick-release formwork support for large-span prestressed concrete beams, comprising: multiple bases arranged side-by-side on a hardened ground; multiple vertically distributed columns on each base; a top support on each column; a connecting plate fixed vertically at four equidistant angles on the side of each column; multiple bolt holes vertically formed on each connecting plate; two horizontal braces and diagonal braces, each bolted to the connecting plates on the sides of two adjacent columns on the same base; and two horizontal braces and diagonal braces, each bolted to the connecting plates on the sides of two adjacent columns on the same row between two adjacent bases. The advantages are: the bolted connection facilitates rapid assembly and disassembly, resulting in high efficiency; the horizontal and diagonal braces connect the columns into a whole, ensuring stability.

The invention discloses a lateral force resisting frame composed of steel reinforced concrete columns and prestressed concrete beams and a construction method, and belongs to the technical field of structural engineering.The lateral force resisting frame comprises the prestressed concrete beams and the steel reinforced concrete columns, prestressed pipes are arranged in the prestressed concrete beams, and the two ends of the prestressed pipes penetrate through the steel reinforced concrete columns; the middle parts of the prestressed pipes are positioned at the bottom of the middle section of the prestressed concrete beam; the single prestressed pipes are symmetrically arranged relative to the axial midpoint of the prestressed concrete beam; the steel reinforced concrete column comprises column-shaped steel, the end of the prestressed pipe penetrates through the column-shaped steel to be provided with an anchorage device, and prestressed tendons penetrate through the prestressed pipe and are connected with the anchorage device. The columnar steel comprises a cross web and a first flange plate at the end of the cross web, the first flange plate is a narrow flange plate, and the prestressed pipe penetrates through the cross web from the two sides of the first flange plate. Compared with a section steel beam, the construction procedure can be simplified in the aspect of construction, and the advantages of reducing the cost, shortening the construction period and improving the construction quality are achieved; and compared with profile steel, the steel bars are lower in material cost and construction measure cost, and the comprehensive manufacturing cost can be reduced.

The invention discloses a prestressed energy storage rib, and relates to the technical field of prestressed structure engineering and building energy storage, in particular to a prestressed concrete beam, and a prestressed energy storage rib body is arranged in the prestressed concrete beam. When the prestressed energy storage rib is used, the prestressed energy storage rib body is composed of a high-strength hollow FRP rib and a battery unit packaged in the high-strength hollow FRP rib. The anchoring electrical integrated end is a core innovation, integrates a mechanical anchoring module, an electrical insulation module and a circuit interface module, disperses anchoring stress through a local reinforcing structure to protect an internal battery cell, realizes electrical isolation by using an insulation isolation sleeve, and ensures reliable connection of a tensioned circuit by using a connecting piece with elastic compensation. The invention further provides a construction method of tensioning and anchoring first and then electrical connection, integration of a building structure and energy storage is achieved, and safe and reliable self-energy-storage capacity is given to major infrastructures.

The application discloses a prefabricated prestressed concrete frame structure system connected by UHPC, which comprises prefabricated concrete upper columns, prefabricated concrete lower columns, prefabricated prestressed concrete composite beams, UHPC node core areas and composite slabs. The upper longitudinal main reinforcement extends out of the bottom surface of the prefabricated upper columns and is directly anchored in the UHPC node core areas, the lower longitudinal main reinforcement extends out of the top surface of the prefabricated lower columns and is directly anchored in the UHPC node core areas, the prestressed reinforcement and the common reinforcement extend out of the end surface of the prefabricated prestressed concrete beams and are directly anchored or bent and anchored in the UHPC node core areas. The structure system not only is convenient and fast in on-site construction and improves the installation efficiency of components, but also can greatly reduce the anchoring length of the reinforcement, greatly reduce the amount of stirrups in the node core areas, avoid the congestion of the reinforcement in the node core areas, reduce the cross-section height of the components, reduce the self weight, improve the crack resistance of the components and thus improve the seismic performance of the overall frame structure.

The invention relates to a prestressed concrete beam and column joint reinforcing method and structure. The method comprises the steps that column surface concrete is chiseled away to form a rough surface, and floor reinforcing steel bars are reserved; split steel hoops are installed, and beam bottom connecting steel plates are welded; after the pre-stressed pipeline is positioned through radar, the chemical anchor bolts are implanted, and the pre-stressed tendons are ensured to be avoided; welding a beam top steel plate to form a closed support; newly-added longitudinal bars are welded in unplugged welding holes of the upper steel plate and the lower steel plate, stirrups are bound, and the longitudinal bars outside the beam width range extend to a floor slab to be anchored; and finally, non-shrinkage grouting materials are poured under pressure, and maintenance is conducted for 7 days or above. The reinforcing structure is composed of steel hoops, upper and lower connecting steel plates, chemical anchor bolts and newly-added steel bars which are wrapped into a whole through grouting materials. The beam body does not need to be cut off, and the functions of the prestressed tendons are completely reserved; the steel hoop and the chemical anchor bolt cooperate to enhance the bearing capacity and the shock resistance of the joint; construction is convenient and efficient, cost is low, and normal use of a building is not affected; and the applicability is wide, and flexible adjustment can be achieved to meet different reinforcing requirements.

This application relates to the field of durability testing technology for concrete components, specifically disclosing an adaptive compensation-type environmental-load coupling testing device for prestressed concrete beams. The device includes an adjustable guide rail frame, an environmental erosion simulation module, a continuous load application module, a prestress state monitoring module, and an adaptive control module. The environmental erosion simulation module sprays an erosive medium onto the prestressed concrete beam; the continuous load application module applies a continuous load to the prestressed concrete beam; the prestress state monitoring module anchors the prestressed concrete beam and monitors its prestress in real time; and the adaptive control module controls the loading state of the continuous load application module based on changes in the prestress of the prestressed concrete beam to compensate for prestress loss caused by environmental erosion. This application maintains a stable stress state under long-term erosion-load coupling, improving the accuracy of the test.

The invention relates to the technical field of fabricated buildings, in particular to a full-fabricated prestressed concrete beam column connecting structure which comprises a prefabricated column, an adjusting plate, a connecting piece and two prefabricated beams. The prefabricated column comprises an upper column and a lower column, the upper column and the lower column are connected through a connecting cylinder in a pouring mode, and the two prefabricated beams are installed at the two ends of the connecting cylinder in the horizontal direction respectively. The connecting piece is installed on the lower column. According to the connecting structure of the full-assembly type prestressed concrete beam column, by arranging the prefabricated column, the prefabricated beam and the connecting piece, after installation is completed, if a heavy object is hung on the prefabricated beam or lap joint is continued, the connecting piece drives the adjusting plate to move towards the side with large bearing force in the horizontal direction at the moment; the length ratio of the adjusting plate in the precast beam on the side with large bearing force is increased, the stress of the two precast beams is balanced, the precast column is prevented from inclining, and the stability of the whole structure is improved.

The utility model provides a variable cross-section prestressed concrete beam and a beam-column connection joint structure, and relates to the technical field of fabricated frame structures. The prestressed concrete beam comprises a precast beam body, beam end connecting pieces are embedded in the two beam ends in the extending direction of the precast beam body respectively and used for being fixedly connected with column side connecting pieces in a node area of a precast column body in a screwed mode. The lower part of the precast beam body is provided with prestress applying areas which are symmetrically arranged relative to the midpoint of the precast beam body in the first direction, and a plurality of prestressed tendons which are distributed at intervals in the second direction are arranged in the prestress applying areas; the arrangement range of the prestress applying area in the first direction is located between two inflection points of the precast beam body; wherein the first direction is the extension direction of the precast beam body, and the second direction is the width direction of the precast beam body.

The invention relates to a prestressed concrete beam parameter identification method and device, and belongs to the technical field of artificial intelligence. The method comprises the following steps: S1, incrementing a beam column equation; s2, nondimensionalization of an incremental beam column equation is carried out; s3, a composite loss function, namely a dimensionless increment differential equation loss function, a boundary loss function and a deflection increment loss function, for the physical information neural network is constructed in cooperation with the dimensionless increment beam-column equation, and a network optimization method and an optimal hyper-parameter are adapted; and S4, guiding PINN training through the deflection increment and the minimum composite loss function to obtain the characteristic deflection and the dimensionless axial force, and inversely calculating the pre-stress and the rigidity. The advanced method and device for identifying the parameters of the prestressed concrete beam are provided in cooperation with the incremental beam column equation and the physical information neural network, the influences of the multi-scale effect, implicit time-varying functions (such as concrete shrinkage creep and steel strand relaxation) and inherent observation deviation can be avoided, and the prestress and rigidity can be accurately identified.

The device comprises a bottom plate and a top plate located over the bottom plate, a first circular through hole is formed in the middle of the bottom plate, a second circular through hole is formed in the middle of the top plate, and the bottom plate and the top plate are connected through a plurality of bearing columns surrounding the first circular through hole at intervals; the bottom plate is matched with an anchor bearing plate on prestressed concrete to be released, the first circular through hole is matched with a working anchorage device on the prestressed concrete to be released, the top plate is matched with an oil cylinder of the jack, and all steel strands on the working anchorage device can pass through the second circular through hole; the interval between every two adjacent bearing columns is not larger than the size of a working clamping piece used for fixing a steel strand. When the prestressed concrete beam body needs to be released, a single steel strand does not need to be sequentially and circularly released, and potential safety hazards existing in non-released steel strands and damage to prestressed tendons caused by multiple times of releasing do not need to be worried about.

This application relates to a construction process for segmented prestressed concrete beams, belonging to the field of prestressed beam construction technology. The process includes the following steps: binding the reinforcement of the first beam segment, installing a water-bleeding component on the beam reinforcement, and installing corrugated pipes; threading the steel strands of the first beam segment; pouring the first beam segment; tensioning the steel strands of the first beam segment; and grouting the corrugated pipes; binding the reinforcement of the first post-cast beam segment and the second beam segment; installing the water-bleeding component of the second beam segment; threading the corrugated pipes of the second beam segment; threading the steel strands of the second beam segment; connecting the steel strands of the first and second beam segments via connectors; pulling the corrugated pipes of the second beam segment through the first post-cast beam segment and splicing the ends of the corrugated pipes of the second beam segment with those of the first beam segment; pouring the second beam segment; and tensioning the ends of the steel strands of the second beam segment away from the first beam segment. This application enables the on-site construction of beams with continuous steel strands in complex environments and improves the tensile strength of small-span beams.

The utility model discloses a pre-stressed concrete T-beam wet joint disassembly-free formwork construction structure which is used for solving the problem that a wet joint construction technology lacks a disassembly-free technology. The construction structure comprises beam bodies and a wet joint arranged between the two beam bodies, and is characterized in that a laminated integrated plate is fixedly mounted below the wet joint and consists of a galvanized profiled steel sheet and a steel bar truss welded on the galvanized profiled steel sheet; the steel bar truss with the three-dimensional space structure is composed of transverse bars bent continuously in an S shape and longitudinal bars perpendicular to the transverse bars, and the steel bar truss and lap joint bars on the side face of the beam body are bound into a whole. Through the implementation of the technology, the laminated integrated plate can play a role of a template and also can play a role of an integrated plate, so that the template is free from being disassembled.

The invention relates to a hybrid girder bridge design method and a hybrid girder bridge, and relates to the technical field of complex line bridge design, and the method comprises the following steps: obtaining initial structure parameters of a hybrid girder and a concrete girder under the same condition based on related design specifications of a steel-concrete composite bridge and a prestressed concrete girder; the mid-span span of the concrete beam is adjusted, so that the maximum bending moments of the middle pier tops in the structural parameters of the concrete beam and the hybrid beam are equal; adjusting the mid-span correlation structure parameters of the hybrid beam to be consistent with the concrete beam, and obtaining the maximum bending moment of the middle pier top after the parameters of the hybrid beam are adjusted; if the variable quantity of the maximum bending moment of the middle pier top after the parameters of the hybrid beam are adjusted is larger than or equal to a set threshold value, the structural parameters of the concrete beam are adjusted, and the maximum bending moment of the middle pier top of the concrete beam is made to be equal to the maximum bending moment of the middle pier top after the parameters of the hybrid beam are adjusted; and adjusting the mid-span correlation structure parameters of the hybrid beam to be consistent with the parameter-updated concrete beam until the maximum bending moment variation of the middle pier top after the parameter adjustment of the hybrid beam is less than a set threshold value.

This invention provides a grouting system for post-tensioning of prestressed concrete beams, solving the problem of local voids easily occurring after grouting of prestressing ducts. The invention includes a concrete structure with pre-set, left-right perforated prestressing ducts. Anchor plates are installed at both ends of the prestressing ducts, with a grouting hole at the center of each anchor plate. The left anchor plate is sealed and fixedly connected to one end of a grouting pipe, which is equipped with a first electronic flow meter and a first valve. The other end of the grouting pipe is connected to the outlet of a concrete pump. Several pressure sensors are equidistantly spaced along the length of the prestressing duct. The right anchor plate is fixedly connected to one end of a grout discharge pipe, which is equipped with a second electronic flow meter and a second valve. The first and second electronic flow meters and pressure sensors are all communicatively connected to a controller, which has a display screen and is connected to the concrete pump control system.

The invention discloses a joint structure for a multidirectional non-orthogonal retard-bonded prestressed beam and a concrete column, and belongs to the field of structural engineering. The structure comprises a concrete column, a concrete column cap wrapping a column body, a prestressed concrete beam, a beam longitudinal bar, a prestressed steel strand and a column cap steel bar composed of a vertical U-shaped steel bar and a horizontal annular stirrup. Beam longitudinal bars penetrate through the column caps to be anchored into the column, and the anchoring length is calculated from the column edge. The prestressed steel strand penetrates through the column cap and the column body and then is anchored through an anchorage device, and the anchoring position can be flexibly arranged on the top face of the column cap, the top face of an opposite-side component or the side edge of the column cap according to whether a horizontal component exists on the opposite side or not. And the vertical U-shaped ribs of the column cap are configured according to the minimum reinforcement ratio. The node design is simplified, complex bending moment calculation is avoided, the using amount and density of the steel bars in the node area are remarkably reduced, smooth strand penetrating and anchoring of the prestressed tendons are guaranteed, and node safety and construction convenience are improved.

To provide a joint structure between a sheath pipe and a pile head block that is rationalized so that the shape and dimensions of the pile head block can be rationalized and the weight of the member can be reduced. [Solution] The pile comprises a steel pile (1), a sheath pipe (5) fixed to the top of the steel pile (1) and filled with concrete, a precast concrete pile head block (3) fixed to the top of the sheath pipe (5), and a PC beam (2) extending horizontally from the pile head block (3), and is PC-pressed and joined using a post-tensioning method with PC steel (9) arranged to penetrate the PC beam (2) and the pile head block (3), and the sheath for inserting the PC steel (9) is arranged to penetrate the top of the sheath pipe (5), and at least part of the sheath is a steel pipe sheath (4b) welded rigidly to the sheath pipe (5), and the PC steel (9) and the steel pipe sheath (4b) bear part of the bending moment transmitted between the sheath pipe (5) and the pile head block (3), and the steel pipe sheath (4b) bears part of the axial force transmitted between the sheath pipe (5) and the pile head block (3).

The invention relates to a locally reinforced full-fabricated prestressed concrete beam column structure system and a construction method thereof. The beam column structure system comprises a precast beam, a beam top longitudinal bar and a beam bottom longitudinal bar of the precast beam extend out, a beam body prestress sleeve is pre-buried in a hogging moment area on the upper portion of a beam body, a prestress bar penetrates through the beam body prestress sleeve, and the lower portion of the beam end of the precast beam is retracted relative to the beam end to form a first retraction area; a connecting steel bar extends out of a column body of the prefabricated column corresponding to a beam top longitudinal bar of the prefabricated beam, a column body prestress sleeve is pre-embedded in the column body prestress sleeve corresponding to the beam body prestress sleeve, a prestress rib is arranged in the column body prestress sleeve in a penetrating mode, and a bracket plate extends out of the prefabricated column corresponding to the first retraction area. According to the beam-column structure system, the bending strength of a bending area of a beam-column connecting joint can be effectively improved, the bearing capacity of a beam column is effectively improved, meanwhile, deformation and bending of the beam column under the load effect can be remarkably reduced through the component, cracks are reduced, and then the durability of the structure is improved.

The utility model discloses a prestressed concrete beam connecting structure for a house building structure. The prestressed concrete beam connecting structure comprises a concrete column; the plurality of connecting ribs are arranged on the concrete column; a concrete beam; the plurality of prestressed main reinforcements are arranged on the concrete beam; the first connecting sleeve is arranged on the connecting rib; the second connecting sleeves are arranged on the prestressed main reinforcements; the connecting column is provided with a large-diameter end and a small-diameter end, the large-diameter end is used for being connected with the first connecting sleeve, and the small-diameter end is used for being connected with the second connecting sleeve. By arranging the first connecting sleeve, the second connecting sleeve and the connecting column, the connecting structure can adapt to prestressed tendons with large diameters, the increasingly-improved house building strength requirement is met, by arranging the large-diameter end on the connecting column, the connecting strength between the concrete beam and the concrete column can be enhanced, and the connecting strength is improved. And the reliability of connection between the concrete beam and the concrete column is improved.

The application discloses a linear-to-folding-line pre-tensioning device and a construction method. In order to overcome the problems of difficult reduction of the prestress loss of a folding-line pre-tensioning prestressed concrete beam in a prestress tensioning process and low tensioning efficiency, the application adopts a turning shaft capable of reducing the turning angle of prestressed steel strands, reduces the prestress loss by reducing the turning angle, and simultaneously adopts an external turning device including a sliding rail and a tensioning sliding block to reduce the construction difficulty and increase the tensioning efficiency.

The present invention discloses a connector for a fully assembled prestressed concrete beam-column, which is arranged between a prefabricated beam and a prefabricated column; the connector includes a column hidden corbel, a beam end steel corbel and a plurality of ductile connectors; the column hidden corbel is pre-buried in the prefabricated column, horizontally arranged in the column node area where the prefabricated column matches the prefabricated beam, and the end extends from the side of the prefabricated column; the beam end steel corbel is pre-buried in the middle position of the connecting end of each prefabricated beam connected to the prefabricated column; and one end of the beam end steel corbel extends from the connecting end of the corresponding prefabricated column and is connected to the corresponding column hidden corbel; a plurality of ductile connectors are all pre-buried in the prefabricated column, horizontally arranged at a position matching a plurality of prestressed threaded steel bars on the upper and lower sides of the prefabricated beam; and each ductile connector is connected to the corresponding prestressed threaded steel bar. The present invention can realize dry connection of prefabricated frame nodes, reduce the workload of wet operations on site, enhance node performance, and achieve energy consumption and replacement of ductile energy dissipators.

The present invention discloses a damage pattern recognition method for a prestressed concrete beam, comprising step 1: collecting acoustic emission data of the whole process of a bending failure test of a prestressed concrete beam, and establishing a verification set, a training set, and a test set database required for neural network calculation; step 2: updating the WOA algorithm by introducing a dynamic adaptive weight, generating an IWOA algorithm, and building an IWOA-LSTM neural network model through a fitness function and a peer relationship; step 3: using the verification set data to complete the structural finalization operation of the IWOA-LSTM, and realizing the hyperparameter optimization of the LSTM; step 4: using the training set data to complete the network finalization operation of the optimized LSTM and finally verifying the effect through the test set data. The method provided by the present invention can avoid the local optimization trap caused by the empirical setting of hyperparameters, has a fast training convergence speed, and has a high pattern recognition accuracy.

This invention discloses a method for modeling a scaled-down model of a large-span prestressed concrete beam. This method achieves the stress characteristics of the actual beam by establishing a scaled-down model beam. Specific operations include: proportionally reducing the geometric dimensions of the actual beam while ensuring the same reinforcement ratio for ordinary steel bars; deriving the prestressing tendon curve equation in the actual beam; determining the prestressing tendon equation in the model using the same method, without considering prestress loss, to ensure the same internal force effect of prestressing in both the actual beam and the model; determining the number of prestressing tendons and the tension control stress in the model; then, considering prestress loss analysis to determine whether the effective prestressing effect is the same in the actual beam and the model beam; if not, returning to the derivation method to re-determine the prestressing tendon equation in the model, repeating the above steps to ensure the same effective prestressing effect; after successful calculation of the scaled-down model, fabricating the scaled-down model beam. The scaled-down model of the large-span prestressed concrete beam obtained by this method facilitates relevant experimental tests on large-span prestressed concrete beams, ensuring experimental accuracy.