2084 results about "Pre stress" patented technology

The application relates to the field of building technology, in particular to a post-tensioned prestressed seamless concrete floor construction method. In the construction preparation step, a strain sensing sensor is arranged, and a steel strand with a protective sleeve is arranged; in the concrete pouring step, concrete with good early strength is adopted; in the prestressed tensioning step, the stress and tension are monitored through a preset sensor, the strain value when the floor first cracks is determined, the initial value for starting the tensioning device is determined, and the tensioning device is controlled to start tensioning operation. Subsequent control is realized through a control system according to the information monitored by the sensor and the instruction control, and the preset threshold value is preferably less than the initial value for starting the tensioning device, so that the tensioning is started before the internal stress of the concrete is insufficient to cause cracks, and the tensioning process is effectively controlled before the cracks are generated, so that the floor is ensured not to generate cracks.

The application discloses a post-tensioned prestressed seamless concrete floor construction method, which comprises the following steps: laying a corrugated pipe; installing a tension end and a fixed end node; inserting a prestressed tendon into the corrugated pipe; installing a strain sensing assembly, wherein the strain sensing assembly comprises stress transmission steel bars and a strain sensing sensor, the stress transmission steel bars comprise coaxially arranged first steel bars and second steel bars, and the two main steel bars are connected through connecting steel bars; an installation gap is left between the end faces of the opposite ends of the first steel bars and the second steel bars, and the strain sensing sensor is installed in the installation gap; pouring concrete, wherein the strain sensing assembly is poured and wrapped in the concrete; and tensioning the prestressed tendon, wherein during the tensioning process of the prestressed tendon, the prestress is controlled, the tensioning elongation value is measured as a check, and the strain value of the concrete is simultaneously referred to. According to the application, the strain condition of the concrete in the prestressed seamless floor construction process can be known by the staff through the strain sensing assembly.

The invention discloses a tunnel construction method for a large deformation section of soft rock, and relates to the technical field of tunnel construction for the large deformation section of the soft rock, and the tunnel construction method for the large deformation section of the soft rock comprises the following steps: drilling shallow large-aperture stress release holes and deep small-aperture stress release holes to form a layered release system; differential pressure grouting is conducted around the stress release holes, and a deep reinforcing ring and a shallow coupling ring are formed; a steel frame is erected, and a three-stage stretching locking bottom supporting assembly is installed to form a closed supporting ring; the bottoms of the adjacent steel frames are crossly connected through prestressed pull rods to form an integral rigid grid; a secondary lining is constructed after the longitudinal attenuation conduction period is judged according to the surrounding rock deformation spatial-temporal characteristics; inverted arch first and then arch wall segmented pouring is adopted, and a delayed expanding agent is doped into arch wall concrete. The method can effectively control surrounding rock deformation in the tunnel construction process of the large deformation section of the soft rock, improves the overall rigidity and stability of a supporting system, ensures that the lining is tightly attached to the surrounding rock, and reduces the construction risk.

The invention relates to the technical field of data processing, and discloses a temperature effect modeling method and system for a concrete tower drum. The method comprises the steps of establishing a finite element model considering joint grading thermal resistance and prestress correction material parameters, adaptively adjusting a time step length according to a solar altitude change rate to calculate a radiation load, obtaining a convergence temperature field through bidirectional coupling iteration of a temperature field and a stress field, and extracting characteristic temperature to train a neural network to realize rapid prediction. According to the invention, the precision and efficiency of temperature effect analysis of the fabricated concrete tower drum are improved.

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 fabricated steel-UHPC external prestressing combined box girder and a construction method and application thereof, and relates to the technical field of bridge engineering, the fabricated steel-UHPC external prestressing combined box girder comprises a prefabricated steel-UHPC combined top plate, a prefabricated steel-UHPC combined bottom plate, a prefabricated steel-UHPC combined web plate, a steel diaphragm plate and an external prestressing system. The box girders are formed by combining prefabricated slabs, the prefabricated web plates are firmly connected with the prefabricated top plate and the prefabricated bottom plate through welded steel plates and post-poured UHPC, and arrangement and tensioning of external prestress are achieved by arranging steel anchor boxes and steering gears in box chambers. According to the combined box girder, the steel and the UHPC are combined to form a structural form that the steel plate is wrapped by the UHPC, and the advantages of high strength, high durability, high toughness, high compactness, low creep and the like of the UHPC and the advantages of high strength, high elastic modulus and weldability of steel are fully utilized, so that the box girder has the advantages of being excellent in structural stress performance, light in overall weight, good in durability, small in later-stage deformation, low in cost and the like. And the hoisting device is especially suitable for bridges in urban rail transit or urban railways.

The invention discloses a wire rod for 2000MPa-level prestressed steel with the large specification of 15mm and a preparation method of the wire rod, and belongs to the technical field of metal material preparation and metal pressure processing. The invention aims to develop a 15mm large-specification high-performance prestressed steel wire rod with a novel component system and a matched production process thereof, the tensile strength of the wire rod is greater than or equal to 1200MPa, and the percentage reduction of area (after aging) is greater than or equal to 30%; the product can be used as a large-specification high-strength high-speed rail plate prestressed steel wire and a 1960-2000MPa-grade high-performance prestressed steel wire and a steel strand. According to the method, the technological process of molten iron pretreatment, converter smelting, LF refining, RH refining, square billet continuous casting, casting billet slow cooling pit slow cooling, casting billet heating, high-pressure water descaling, controlled rolling and controlled cooling and PF line heat preservation channel slow cooling and a complete and controllable production process system are adopted; and the harsh requirements of large-size high-performance prestressed materials of modern important projects on the performance of the wire rod are met.

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

The invention discloses a chlorine salt corrosion resistant prestressed concrete solid square pile and a construction method thereof, a cementing material of a pile body concrete body of the square pile comprises a mineral admixture accounting for 50%-70% of the total mass of the cementing material, and the cementing material adopts Portland cement; sacrificial anode blocks electrically connected with the main reinforcements are embedded in the pile body concrete body. The pile body concrete body is doped with a composite corrosion-resistant and rust-resistant agent; the outer surface of the pile body concrete body is coated with polyurea waterproof paint or epoxy seal primer. An electromigration type corrosion inhibitor and a microcapsule containing bacillus are doped into the pile body concrete body; the prestressed main reinforcements are steel reinforcements with anti-corrosion coatings; and fiber bragg grating sensors are pre-embedded around the prestressed main reinforcements. The mixing proportion of the concrete body of the pile body is specially designed for fixing and blocking chloride ions, an inapplicable sulfate-resistant cement scheme is abandoned, and the chlorine salt resistance is improved from the source of materials.

The invention discloses a pile head treatment method applied to a static load test, and relates to the technical field of prestressed pipe pile static load tests, and the pile head treatment method comprises the following steps: step 1, pile head treatment: carrying out muck cleaning work on a cut pile head; secondly, a buffer protection structure is poured on the pile head through the multifunctional pile head processing device; the multifunctional pile head processing device comprises a diagonal bracing structure in lap joint with the upper opening edge of an inner cavity of a pile head, a baffle falling on the diagonal bracing structure, an inner formwork surrounding the baffle and an outer formwork surrounding the outer edge of the pile head, and the portion between the inner formwork and the outer formwork and the portion above the baffle are used for pouring to form buffer layers; the multifunctional pile head device further comprises arc-shaped steel pile hoops, the two steel pile hoops are spliced and then arranged on one section of the pile head pouring buffer layer of the pipe pile in a sleeving mode, and the steel pile hoops are matched with the buffer layer to form a buffer protection structure. The method has the effect of reducing the probability that the static load test is influenced by the damage of the pile head of the prestressed pipe pile.

The self-adaptive staged energy consumption friction-shear yield composite damper comprises a friction energy consumption unit, an inner friction plate, an outer friction plate, at least two shear energy consumption units and an H-shaped steel plate, wherein the inner friction plate and the outer friction plate are located on the friction energy consumption unit, and the H-shaped steel plate is located at the tail end of the friction energy consumption unit and used for fixing the friction energy consumption unit. The prestressed bolt sequentially penetrates through the inner friction plate and the outer friction plate on the friction energy dissipation unit and the shear energy dissipation unit and is connected with the inner friction plate and the outer friction plate on the friction energy dissipation unit and the shear energy dissipation unit through at least one pair of linkage rods, and the two ends of the friction energy dissipation unit are connected to beam-column joints respectively. The linkage rod does not make contact with a linkage rod penetrating hole of the shearing energy dissipation unit during displacement, and only the friction energy dissipation unit works; and the linkage rods make contact with the linkage rod penetrating holes in a displacement mode, the shear energy dissipation devices are fixed, the shear plates are subjected to shear deformation, and the earthquake displacement response of the structure is effectively reduced through staged energy dissipation and the displacement amplification effect.

The present application relates to the technical fields of prestressed positioning mesh welding, and especially relates to a multi-stage adjusting mechanism for prestressed positioning mesh, which is provided with a welding control module, an information capturing module, a displacement analysis module and a welding correction module. The transverse steel bars are laid on the longitudinal steel bars through the laying unit, the intersection positions of the longitudinal steel bars and the transverse steel bars are welded through the welding unit, the vibration intensity change curve is drawn through the information capturing module, it is determined whether there is vibration allowance abnormal phenomenon at the intersection positions and the vibration allowance abnormal category of the intersection positions is determined through the abnormal analysis unit, the welding correction mode is selected through the welding correction module, and then, the quick abnormal risk identification according to the actual situation in the steel bar welding and sticking process is realized, the abnormal welding positions are classified and processed, the welding correction mode is adaptively adjusted, and the production efficiency and welding reliability of the prestressed positioning mesh are improved.

The invention relates to the technical field of wind power towers, and discloses a concrete-filled steel tube truss type hybrid wind power tower which comprises a tower drum, a plurality of steel tube beams and a plurality of steel tube beams. The truss unit is suitable for supporting the tower drum; the transition unit is arranged between the tower drum and the truss unit so as to connect the tower drum with the truss unit; the bearing platform unit is arranged at the end, away from the tower drum, of the truss unit and suitable for bearing the truss unit; the truss unit comprises at least one pipe body, and concrete is poured in the pipe body. And the constraint stranded wires are tensioned in the axial direction of the pipe body and anchored to the transition unit and the bearing platform unit correspondingly, and the constraint stranded wires are at least arranged outside the pipe body. According to the concrete-filled steel tube truss type hybrid wind power tower, the constraint stranded wires are arranged outside the tube body, the situation that the cable penetrating process is complex and cannot be observed is avoided, the situation that the constraint stranded wires are mutually wound in the cable penetrating process is avoided, constructors can conveniently and directly observe the tensioning state outside, and it is ensured that prestress is accurately applied.

The invention discloses a self-resetting multi-section prefabricated assembled pier and a construction method, the self-resetting multi-section prefabricated assembled pier comprises a prefabricated cover beam, a pier column and a pier bearing platform, the pier column is formed by splicing a plurality of prefabricated sections, and is connected with the prefabricated cover beam through the prefabricated section located at the top; the prefabricated bent cap is connected with the pier bearing platform through a prefabricated section located at the bottom in a bell and spigot joint mode, and the non-adhesive prestressed tendons are connected with the prefabricated bent cap and the pier bearing platform and provide self-resetting capacity for the pier. According to the multi-section prefabricated assembled pier with the self-resetting capacity and the construction method, the formworks are prefabricated in a unified mode in a factory, the efficiency is improved while the prefabrication and construction cost is reduced, the mode of prefabricated section splicing and shallow socket connection is adopted, construction in narrow and complex terrains is facilitated, prestressed tendons used for self-resetting are arranged, and the construction efficiency is improved. The overall anti-seismic performance is improved, the integrity, rigidity and bearing capacity of the assembled pier are improved, the service life is prolonged, and meanwhile the maintenance cost is reduced.

The invention discloses a foundation pit supporting structure deformation and internal force calculation method. In the calculation method, an out-pit constraint stiffness matrix is introduced as a calculation factor, and a stiffness coefficient is iteratively calculated; the calculation method comprises the following steps: S1, constructing a foundation pit supporting structure calculation model; s2, a displacement-load total balance equation of the supporting structure under the undetermined supporting working condition of the foundation pit is determined; s3, a servo support is installed, prestress is loaded, a constraint stiffness matrix is introduced, a stiffness coefficient is calculated in an iterative mode, a displacement-load total balance equation of the supporting structure is established step by step, and the deformation condition of the supporting structure is analyzed and calculated; s4-5, the steps S2 to S3 are repeated until installation of all servo supports and prestress loading are completed, and displacement and internal force of the supporting structure are calculated; and S6, the foundation pit continues to be excavated to the pit bottom, deformation and internal force under all working conditions are calculated, and regulation and control calculation can be conducted in the process. By means of the calculation method, accurate calculation of deformation and internal force of the foundation pit supporting structure under the servo supporting effect can be achieved.

The invention relates to the technical field of tailing concrete poles, in particular to a prestressed tailing concrete pole and a manufacturing method thereof, and the prestressed tailing concrete pole comprises the following components in parts by mass: 550-600 parts of modified iron tailings, 180-200 parts of a prestressed modifier, 500-600 parts of slag, 30-45 parts of silica fume, 180-200 parts of fly ash, 6-8 parts of a polycarboxylate superplasticizer, 5-10 parts of a viscosity modifier and 5-10 parts of an auxiliary enhancer. Through the synergistic effect of the prestress modifier, the viscosity modifier and the modified iron tailings, bleeding and segregation of the high-volume tailing concrete in the vibrating process are prevented, the homogeneity of the material is ensured, the formed electric pole has extremely high internal compactness and a smooth surface, and therefore the freeze-thaw resistance and durability of the electric pole are greatly improved. The modified iron tailings are used for replacing part of traditional cementing materials and aggregates, so that the production cost is remarkably reduced, extremely high additional value is given to industrial solid wastes, the problems of environmental risk and land occupation caused by stockpiling of the industrial solid wastes are solved, and the national green development strategy is met.

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 discloses a method for predicting the prestress loss of a steel cable in the whole fire process, and belongs to the technical field of bridge engineering. The method comprises the steps that a finite element heat transfer analysis model of the steel cable is established based on ABAQUS finite element software, and a finite element thermal coupling analysis model of the corresponding steel cable is established; and loading the heat transfer analysis result of the steel cable as a pre-stress field into a thermal-mechanical coupling analysis model, and simulating to obtain the pre-stress loss evolution condition of the steel cable in the whole fire process. According to the method, the prestress loss of the steel cable in the whole fire process is analyzed through numerical simulation, and compared with a traditional fire test method, the research cost is greatly reduced, and the analysis efficiency is remarkably improved; the prediction method provided by the invention can be directly applied to engineering practice, provides a scientific basis for evaluating the stress state of the steel cable structure after the fire, has an important reference value for guiding the formulation of a post-disaster repair scheme, and is beneficial to improving the fire-resistant safety performance of an engineering structure.

The invention relates to the technical field of intelligent optimization design, in particular to a bridge prestressed steel beam intelligent optimization design method based on multi-factor coupling, and the method comprises the steps: carrying out the quantitative modeling of a plurality of parameters in the arrangement process of a bridge prestressed steel beam, achieving the precise expression of controllable variables, and improving the design precision of the bridge prestressed steel beam. The overall search capability of the arrangement scheme under multi-target tradeoff is enhanced, the rationality and stability of steel beam distribution are integrally improved, the structure local overload risk is reduced, an energy function sequence is constructed through indexes such as a midspan displacement value, a section stress ratio and the total length, the quality of a solution set is controlled by utilizing an energy difference value, intervention and screening of a residual value are introduced, and the stability of the structure is improved. The robustness of the design under the multivariable condition is enhanced, through logic judgment of displacement and counterforce, unqualified arrangement is eliminated, feasible arrangement output under structural consistency is achieved, structural efficiency and material use economy are enhanced, and design reliability, optimization solution efficiency and structural response control precision are remarkably improved.

This invention relates to the field of oilfield thermal recovery well technology, and discloses a well completion process device, a column-type ground anchor, and a method for increasing the prestress of the oil layer casing. The well completion process device includes a surface casing (1) located below the surface, an oil layer casing (2), and a casing head body (3). The oil layer casing is connected to the inner surface of the casing head body via a connecting assembly (40). A column-type ground anchor (500) is connected to the bottom of the oil layer casing. The column-type ground anchor includes an anchor claw (502) and a plunger body (530). A liquid outlet (501) is formed on the column-type ground anchor. The anchor claw can extend out of the side wall of the plunger body and insert into the formation. Cement can be discharged from the liquid outlet to seal the annular gap between the oil layer casing and the formation. This invention uses hydraulic oil to insert the anchor claw into the formation, pulling the oil layer casing to a preset load. After the oil layer casing is pulled up, it is clamped to the inner wall of the casing head body via the connecting assembly, thus increasing the prestress.

The invention discloses a prestressed laminated slab as well as a manufacturing method and a using method thereof, and belongs to the technical field of constructional engineering. The prestressed laminated slab comprises a transverse pipeline, a prefabricated concrete bottom plate, reinforcing ribs, longitudinal prestressed tendons and transversely distributed steel bars, the transverse pipelines are arranged at intervals in the first direction, are partially embedded in the prefabricated concrete bottom plate and are parallel to the second direction; longitudinal prestressed tendons and transverse distributed steel bars are arranged in the prefabricated concrete bottom plate. The reinforcing ribs are arranged at intervals in the first direction, and the bottoms of the reinforcing ribs are fixed to the prefabricated concrete bottom plate. The first direction is the length direction of the precast concrete bottom plate, and the second direction is the width direction and is perpendicular to the precast concrete bottom plate. The reinforcing ribs can adopt various structures such as concrete ribs and steel pipe trusses, and light material blocks are arranged on the prefabricated concrete bottom plate and arranged in an area defined by the reinforcing ribs and the transverse pipelines. The manufacturing method comprises the following steps: cleaning a mold table, assembling the mold, distributing the reinforcements, tensioning, fixing the pipeline and the reinforcing ribs, pouring, maintaining and the like. During use, the two-way prestressed floor slab is formed through hoisting, pipeline connection, reinforcement, reinforcement penetrating, pouring, tensioning and grouting. The problems that an existing laminated slab is poor in stress performance, prone to cracking, insufficient in bonding strength and the like are solved, bidirectional prestress design, consistent bidirectional rigidity of a floor system and bidirectional force transmission performance are achieved, the integrality and crack resistance of a floor slab are improved, the self weight is reduced, the steel consumption is reduced, the construction process is simplified, and the laminated slab is suitable for large-span and heavy-load building scenes.

The invention discloses a replaceable energy dissipation type prestress assembly type beam-column joint and a construction method thereof. The replaceable energy dissipation type prestress assembly type beam-column joint comprises a prefabricated column, a prefabricated beam, an angle steel connecting piece, a viscous damper, FRP cloth and a prestress tensioning piece. The FRP cloth is pasted to the joint of the prefabricated beam and the prefabricated column, angle steel connecting pieces fixed to the prefabricated beam and the prefabricated column are arranged on the outer side of the FRP cloth, and the two angle steel connecting pieces on the upper side are provided with viscous dampers arranged in the inclined direction. The prestressed tensioning part is of a downwards-protruding arc-shaped structure, a first hole channel and a second hole channel which are matched with the prestressed tensioning part are formed in the prefabricated beam and the prefabricated column respectively, anchoring blocks are arranged at the positions, corresponding to the first hole channel, of the upper end face of the prefabricated beam, the prestressed tensioning part is arranged in the hole channels in a penetrating mode, and the two ends of the prestressed tensioning part are anchored to the corresponding anchoring blocks respectively. The FRP cloth is adopted to enhance the integrity and durability of the joint, the downwards-protruding prestress tensioning piece can resist the sagging moment of the joint and cooperates with the viscous damper to efficiently dissipate energy, and rapid repairing is achieved by replacing the energy dissipation connecting piece.

The invention relates to the technical field of deep foundation pit engineering construction, in particular to a first-supporting-and-second-supporting system construction method based on back pressure soil of a deep foundation pit of a temporary operating subway, and the method comprises the following steps: aiming at the construction problem of the deep foundation pit of the temporary operating subway, forming a collaborative supporting system by reserving a back pressure soil body, a supporting pile and a top beam; layered excavation is carried out by adopting a support-first and support-second process, and a next layer is excavated after support installation and prestress application are completed; deep foundation pit backfilling and steel support layered dismantling are executed step by step along with commercial main body structure construction; after the commercial main body reaches the preset stage, integrated construction including static cutting, rigid connecting component pre-embedding for settlement prevention and middle-embedded type water-stop belt waterproofing is conducted on the subway channel; and a real-time monitoring system is combined to ensure construction safety and subway structure stability. The method can effectively balance the stability of the deep foundation pit and metro protection requirements, improves the construction efficiency, solves the problems of settlement and leakage of construction joints, and is suitable for deep foundation pit engineering close to an operating metro.

The application discloses a pre-tensioning method bridge threaded steel grading step-by-step synchronous tensioning device and tensioning method. The device comprises a steel beam, a jack assembly, a support assembly, a large counterforce frame, an anchoring assembly, a hydraulic pump station, an inclination sensor and a control assembly. The jack assembly comprises an upper jack unit and a lower jack unit. The piston rod ends of the upper jack unit and the lower jack unit are connected with the large counterforce frame through universal ball head structures. The hydraulic pump station is connected with the upper jack unit and the lower jack unit respectively. The inclination sensor is arranged on the side surface of the large counterforce frame. The control assembly is electrically connected with the hydraulic pump station and the inclination sensor respectively. The application can adapt to the tensioning working condition of the differentiated reinforcement on the upper and lower beam bodies, realize the collaborative synchronous tensioning of the jacks with different tonnages, and has the advantages of uniform tensioning stress, high displacement control precision, simple structure, economy and reliability, effectively reduced beam body deformation risk and improved overall quality of the bridge prestress construction.

This invention relates to the field of bridge reinforcement technology, and more particularly to an external prestressed reinforcement structure for bridges, including a bridge body and reinforcement components. The reinforcement components include a fixing member with a fastening bolt at its lower left end. The fixing member is threadedly connected to the bridge body via the fastening bolt. This invention, by incorporating components such as a support plate, sliding roller, elastic compression plate, and return spring, can automatically adjust its position during the natural shrinkage of the concrete repair layer. The sliding roller slides at the bottom of the elastic sealing plate, and in conjunction with the tension of the return spring, continuously applies reverse pressure, ensuring that the sealing plate remains tightly fitted to the repair layer. The elastic compression plate, under the action of the support spring and telescopic sleeve, can evenly distribute pressure, adapting to the curvature changes of the repair layer, avoiding localized stress concentration, and ensuring that the sealing protection of the concrete repair layer does not fail during the shrinkage and shaping process, preventing crack recurrence.

The present invention relates to rebar-free prestressed concrete and to a forming method therefor. The rebar-free prestressed concrete comprises: a base layer which is a mortar, concrete or neat slurr

The application provides a rotatable pull rod installed on the top of an I-beam template, belonging to the field of prestressed concrete bridges, which comprises a fixed bottom plate, a movable bottom plate arranged on one side of the fixed bottom plate, a telescopic mechanism connecting the movable bottom plate and the fixed bottom plate, a positioning clamping block fixedly connected to the bottom of the fixed bottom plate and the movable bottom plate, and a U-shaped frame fixedly connected to the side end of the fixed bottom plate and the movable bottom plate. The pushing of the driving spring is offset by the driving pawl, and the driving pawl is unlocked. Under the pushing of the reset coil spring, the rotating shaft is rotated, the rotating shaft drives the driving pawl to rotate, the driving pawl is reset, and the two driving pawls are reset one by one, so that the fixing of the device and the two I-beam templates is conveniently released, the device is quickly disassembled, the device is quickly assembled and disassembled, the installation mode between the butterfly buckle and the screw rod is avoided, the installation speed is improved, and the flow operation of the beam bench is accelerated.

The invention discloses a composite reinforcing method and device for a soft soil levee slope based on prestressed corrugated pile emergency support, and the method comprises the steps: investigating a to-be-reinforced levee slope and engineering geological conditions in an influence range of the to-be-reinforced levee slope, and obtaining investigation data; calculating by setting a slope stability analysis strategy to obtain a natural state safety coefficient; the state of the to-be-reinforced levee slope is judged, and a state result is obtained; according to a state result, a cement-soil mixing pile temporary construction platform, a composite reinforcing area, a prestress wave-shaped pile and a three-dimensional drainage system are designed; and performing construction preparation and reinforcement construction according to the design scheme. The problems of temporary emergency and permanent splitting, construction disturbance instability, high cost, river channel occupation, difficulty in considering efficiency and ecology and the like in the prior art are solved.

The application discloses a kind of based on bulk body pushing prestressed end help mining chamber filling method, including bulk body broken material filling, setting gravity pile, filling paste filling layer, pushing machine heap loading, chamber wall protection, chamber mouth closure, supplementary support and the like steps.The present application does not need to construct fixed facilities, with the advantages of flexible deployment, low investment cost, etc., while effectively solving the problem that loose material cannot support roof, suitable for short service life, slope overburden resource limited open pit end temporary mining operation;The unique design of gravity pile can enhance the stability of gravity pile, increase the friction at the bottom, prevent gravity pile from slipping or overturning;Artificial segmentation is carried out on the mining chamber, blocking the flow of bulk body broken material in the filling process towards the chamber mouth direction;It is convenient for prestressed segment loading;Provide a relatively closed space for the action of paste filling layer;Bulk body broken material filling layer can not only make up the settlement deformation, but also provide supplementary support force, while not increasing filling cost too much.

The invention discloses a soft soil area transformer substation multi-load foundation structure which comprises pipe pile bearing platforms, prestressed pipe piles and integrally-arranged beam plate type rafts, and the multiple pipe pile bearing platforms are arranged at the positions, corresponding to an accident oil pool area, a road cable trench area, a power distribution building area and a main transformer area, below the beam plate type rafts. Two vertically-arranged prestressed pipe piles are connected to the lower portion of each pipe pile bearing platform corresponding to the accident oil pool area, two vertically-arranged prestressed pipe piles are connected to the lower portion of each pipe pile bearing platform corresponding to the road cable trench area, and 3-8 prestressed pipe piles are connected to the lower portion of each pipe pile bearing platform corresponding to the power distribution building area according to the load difference. And six pre-stressed pipe piles which are vertically arranged are connected below each pipe pile bearing platform corresponding to the main transformer area. Continuous load transmission and overall stress of the foundation structure can be achieved, the problem that differential settlement of all areas is too large is effectively solved, the structural durability is improved, the local stress concentration risk is reduced, and the bearing reliability is improved.