UHPC support and crown beam slide rail type connecting structure and method

Abstract

The invention discloses a UHPC (Ultra High Performance Concrete) support and crown beam slide rail type connecting structure and method, solves the defects in the existing steel support system and reinforced concrete support system, and considers the mechanical property of the support and the rapid construction convenience. The structure comprises a UHPC prefabricated support and a top beam, the UHPC prefabricated support is structurally divided into a support main body and mounting parts located at the two ends of the support main body, the mounting parts are parts for assembly construction with the top beam in a foundation pit support, the support main body is a UHPC prefabricated part composed of longitudinal bars and UHPC, the cross section of the UHPC prefabricated part is I-shaped, rectangular or circular, and the longitudinal bars and the UHPC prefabricated part are made of steel. A bracket is arranged on the top beam, and the top beam and the mounting part are mounted in a quick assembly manner. The connecting structure has detachability, is convenient to mount and dismount, can solve the problems that the first support of the foundation pit cannot be recycled and wastes labor and materials at present, improves the material utilization rate, and is easier to popularize and apply in practical application.

Description

Technical Field

[0001] The invention relates to a UHPC support and installation method, and belongs to the technical field of subway foundation pit construction. Background Art

[0002] At present, there are more and more subway foundation pit projects, and there are more and more supports in the foundation pit. The first support in the subway foundation pit is cast-in-place concrete support, which needs to be demolished after the construction is completed. It cannot be recycled and is a waste of materials and labor.

[0003] In foundation pit engineering, according to the different supporting materials, it can be divided into steel support system and reinforced concrete support system.

[0004] Steel support adopts steel pipe material component support system, which has the advantages of fast construction speed and multiple reuse. However, the disadvantage of steel support is that its compressive performance is poor (reinforced concrete support has strong compressive performance). When the span of steel support is large, it may become unstable. Once one of the steel supports becomes unstable, a chain reaction of failure will occur, increasing the safety risk of the foundation pit.

[0005] The advantages of the cast-in-place reinforced concrete support system are high overall rigidity, small deformation, safety and reliability. The disadvantages are that its construction process adopts the wet method of cast-in-place concrete, which requires a certain amount of curing time, and earth excavation is relatively inconvenient. The overall construction period is long, it is difficult to shape, and it cannot be disassembled and reused.

[0006] Therefore, neither the steel support system nor the concrete support system can meet the needs of high-performance support.

[0007] UHPC (ultra-high performance concrete) is an ultra-high performance concrete with excellent mechanical properties, which is made of fine sand as aggregate and mixed with fine steel fibers. Its strength (tensile, compressive, torsion), toughness and durability are better than ordinary concrete. Therefore, it has broad application prospects in the field of subway foundation pit construction technology. Summary of the invention

[0008] In order to solve the deficiencies of the prior art, the present invention provides a UHPC support, an assembled installation structure and a method, which is a new and reusable support system, which solves the drawbacks of the existing steel support system and reinforced concrete support system, and takes into account both the mechanical properties of the support and the convenience of rapid construction.

[0009] The technical solution adopted by the present invention to solve the technical problem is: A UHPC support and crown beam sliding rail connection structure, comprising a UHPC prefabricated support and a crown beam, characterized in that the UHPC prefabricated support is structurally divided into a support body and mounting parts located at both ends of the support body, the so-called mounting part refers to a part for assembly construction with the crown beam in the foundation pit support, wherein the support body is a UHPC prefabricated component composed of longitudinal reinforcement and UHPC, and its cross-section is I-shaped, rectangular or circular, a corbel is arranged on the crown beam, and a socket and a connector are used for rapid assembly installation between the crown beam and the mounting part.

[0010] Furthermore, the connector is fixed on the mounting portion, and the connector is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate, a shear key and a long hole are provided on the longitudinal steel plate, and the socket is pre-buried in the crown beam, and the socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure, and the plug-in direction is from top to bottom, and after being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is provided at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

[0011] Furthermore, the connector is fixed on the crown beam. The connector is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long strip hole are provided on the longitudinal steel plate, and the socket is pre-buried in the installation part. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom, and after being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is provided at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

[0012] Furthermore, the longitudinal dimension of the T-shaped slot is significantly larger than the thickness of the transverse steel plate in the above-mentioned T-shaped connector. After the connection is completed, the UHPC prefabricated support has space for longitudinal position adjustment relative to the crown beams on both sides. During the construction process, the gap between the connector and the T-shaped slot is filled by adding a rigid pad, so that the two ends of the UHPC prefabricated support and the crown beams on both sides form an axial force fit.

[0013] Furthermore, the connector is fixed on the mounting portion, and the connector is a stem-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate, a shear key and a long hole are provided on the longitudinal steel plate, and the socket is pre-buried in the crown beam, and the socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure, and the plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is provided at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

[0014] Furthermore, the connector is fixed on the crown beam. The connector is a stem-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long hole are provided on the longitudinal steel plate, and the socket is pre-buried in the installation part. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom, and after being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is provided at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

[0015] Furthermore, ear walls are provided on both sides of the corbel or the crown beam, and the ear walls constrain both sides of the UHPC prefabricated support installation part.

[0016] Furthermore, the crown beam may be a reinforced concrete crown beam or a steel structure crown beam.

[0017] A method for connecting a UHPC support and a crown beam slide-type connection structure, comprising a UHPC prefabricated support and a crown beam, characterized in that the UHPC prefabricated support is structurally divided into a support body and mounting parts located at both ends of the support body, the so-called mounting part refers to a part for assembly and construction with the crown beam in the foundation pit support, wherein the support body is a UHPC prefabricated component composed of longitudinal reinforcement and UHPC, and its cross-section is I-shaped, rectangular or circular, a corbel is arranged on the crown beam, and the crown beam and the mounting part are quickly assembled and installed through a socket and a plug-in, the plug-in is fixed to the mounting part, the plug-in is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate, a shear key and a long strip hole are arranged on the longitudinal steel plate, and the socket is pre-buried in the crown beam, the socket has a T-shaped slot, and the two are connected through a T-shaped plug-in structure, and the plug-in direction is from top to bottom, comprising the following steps: S1: Forming of the crown beam: Process the socket and weld the anchor steel bars on the back side of the socket, avoiding the longitudinal bars of the crown beams on both sides. After processing, the socket is galvanized as a whole, and the anchor steel bars of the socket are embedded in the casting mold cavity of the crown beams on both sides of the foundation pit, ensuring that the slot in the main body of the socket is located outside the casting template, and the T-shaped slot is reserved, and the upper side of the T-shaped slot is flush with the upper surface of the crown beam; erect the casting template at the crown beam and the corbel position, install the steel cage inside the crown beam, and cast ordinary concrete at the same time as the crown beam. After curing for 72 hours, remove the casting template, set a rubber bearing above the corbel, and set an ear wall at the same time; S2: Forming of UHPC prefabricated support: Processing connectors, welding on longitudinal steel plates to form shear keys, milling grooves to form holes, welding the longitudinal steel plates vertically to the transverse steel plates to form a T-shaped profile, embedding connectors at both ends of the prefabricated UHPC prefabricated support casting template, and the outer ends of the connectors extend outward from the end faces of both ends of the prefabricated UHPC prefabricated support, using UHPC slurry for casting and high-temperature steam curing for 24 hours, and then removing the mold and curing for 14 days; S3: Transportation and hoisting: Use hoisting equipment to hoist the UHPC prefabricated support as a whole to the area to be supported in the foundation pit, adjust the angle and state of the UHPC prefabricated support so that the plug-in is located directly above the socket, and then slowly drop it, and try to insert both ends of the UHPC prefabricated support synchronously, and place the rubber bearing; S4: Adjustment and fixation. After plugging in place, measure the verticality between the UHPC prefabricated support and the crown beams on both sides. Select a fixed point on the crown beam as the measurement reference point. Install the total station on a stable bracket to ensure that the instrument is level and stable. Align the total station with the reference point for initial settings. Use the laser ranging and angle measurement functions of the total station to measure multiple points on both sides of the prefabricated support and the crown beam. Directly read and record the verticality data. According to the measurement results, adjust the verticality between the UHPC prefabricated support and the crown beam until the three form an H-shaped support structure. Use a steel pad to insert it into the matching gap between the connector and the socket. Fix the UHPC prefabricated support to the lower corbel through the rubber support. Comprehensively check the stability of the support system and confirm that all connection parts are stable and reliable.

[0018] The beneficial effects of the present invention are: (1) The present invention is detachable and convenient to install and disassemble. It can solve the problem that the first support of the foundation pit cannot be recycled and is labor-intensive and material-intensive, thereby improving material utilization. In addition, the connection structure is easier to promote and apply in practical applications.

[0019] (2) The present invention can make full use of the excellent compressive and tensile strength and good durability of UHPC materials, significantly reduce the cross-sectional size of the structure, improve construction efficiency, extend service life, and reduce the total life cycle cost.

[0020] (3) The verticality between the UHPC prefabricated support and the crown beams on both sides can be fine-tuned. This adjustment includes both the angle adjustment in the horizontal plane and the angle adjustment in the vertical plane. That is, the plugs at both ends of the UHPC prefabricated support in the present invention can slide vertically downward along the slots for plugging and height adjustment in the vertical plane, and can also be adjusted along the horizontal plane. After adjustment, the verticality of the three is optimized, thereby optimizing the axial tension and pressure that the UHPC prefabricated support can withstand, improving the support effect, and solving the problem of complex force and easy damage at the connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the overall construction effect of Example 1.

[0022] Figure 2 This is a process diagram for plug connection.

[0023] Figure 3 This is a schematic diagram of the plug-in connection in place.

[0024] Figure 4 It is a three-dimensional diagram of the socket in the first embodiment.

[0025] Figure 5 It is a three-dimensional diagram of the connector in the first embodiment.

[0026] Figure 6 It is a three-dimensional diagram of the connector in the second embodiment.

[0027] Figure 7 It is a three-dimensional diagram of the socket in the second embodiment.

[0028] Figure 8 This is a three-dimensional diagram of the UHPC prefabricated support in Example 3.

[0029] Fig. 9 This is the overall structural diagram of Example 3.

[0030] Fig.10 for Fig. 9 A partial enlarged view of point A in the middle.

[0031] Fig.11 It is a three-dimensional diagram of the socket in the third embodiment.

[0032] Fig.12 It is a three-dimensional diagram of the connector in the third embodiment.

[0033] In the figure: 100 UHPC prefabricated supports, 110 connector, 111 transverse steel plate, 112 longitudinal steel plate, 1121 shear key, 1122 long hole, 120 supporting body, 200 crown beams, 210 ox leg, 220 socket, 221 T-shaped slot, 222 anchor steel bar, 230 ear wall, 240 rubber bearings, 300 Rigid Pad. DETAILED DESCRIPTION

[0034] This embodiment first introduces a UHPC prefabricated support. As an industrialized prefabricated component, the UHPC prefabricated support is prefabricated in a prefabrication factory and has the advantages of high standardization and high surface molding quality. The formed UHPC prefabricated support is transported and hoisted to meet the requirements of prefabricated construction.

[0035] In the following embodiments, the directional noun longitudinal refers to the length direction of the support, also called the axial direction, represented by the X-axis, and the lateral refers to the length direction of the crown beam, represented by the Y-axis.

[0036] Embodiment 1: refer to Figures 1 to 5 In the series of examples, the UHPC prefabricated support 100 is structurally divided into a support body 120 and an installation part with a connector 110 as the main body located at both ends of the support body. The so-called installation part refers to the part that is assembled and constructed with the crown beam in the foundation pit support, which is used to meet the requirements of rapid installation and rapid disassembly, and through this disassembly and assembly, the UHPC prefabricated support can be recycled and reused. The support body is a UHPC prefabricated component composed of longitudinal reinforcement and UHPC, and its cross-section is preferably I-shaped, and can also be rectangular, circular or similar structures. The I-shaped has the advantages of torsion resistance and bending resistance, and has higher strength with the same material. The installation part is a T-shaped cross-section connector 110 as a whole, and the connector is fixed at both ends of the UHPC prefabricated support. Specifically, the connector is a T-shaped profile formed by welding a transverse steel plate 111 and a longitudinal steel plate 112, and is further reinforced by welding triangular ribs at the joints of the transverse steel plate and the longitudinal steel plate. At the same time, a shear key 1121 and a long hole 1122 are provided on the longitudinal steel plate 112. The provision of the shear key and the long hole can enhance the bonding force with the UHPC material, and improve the shear resistance between the longitudinal steel plate and the UHPC when the mounting portion is subjected to axial pressure.

[0037] Furthermore, the shear key 1121 can be a shear nail or a short steel bar.

[0038] Furthermore, a shear rib is welded at the end of the longitudinal steel plate, and the width of the shear rib is about three times the thickness of the longitudinal steel plate, which can also improve the shear resistance between the longitudinal steel plate and the UHPC.

[0039] A crown beam 200, which can be a reinforced concrete crown beam or a steel structure crown beam, is described based on a reinforced concrete crown beam in this embodiment. The construction process and technical points of the crown beam are as follows: The crown beam 200 is provided with a corbel 210 , which may be continuous or discontinuous in the horizontal direction, and serves to provide a support point for the UHPC prefabricated support.

[0040] A socket 220 is pre-embedded on the crown beam 200 according to the drawing requirements. The socket is located above the corbel and is used to install the above-mentioned UHPC prefabricated support. That is, a socket 220 is fixedly installed on the crown beam by pre-embedding. The socket is a rectangular structure and has a T-shaped slot 221 in the socket. The T-shaped connector 110 in the above-mentioned UHPC prefabricated support is plugged into and matched with the T-shaped slot 221, and the plugging direction is from top to bottom. After being plugged into place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing 240 is arranged at the mating surface between the bottom of the UHPC prefabricated support and the crown beam corbel, which can ensure the stability of the position of the UHPC prefabricated support on the corbel, and can also transfer loads and deformations, shock absorption and leveling. That is to say, through the setting of the rubber bearing, the vertical load and horizontal load borne can be effectively transferred to the corbel, ensuring the overall stability and safety; the rubber bearing has good elasticity and adaptability, and can adapt to the expansion and contraction deformation of the UHPC prefabricated support under the influence of environmental factors such as temperature and humidity, as well as the deformation caused by other loads, thereby extending the service life of the support.

[0041] Furthermore, a pair of ear walls 230 are provided on the above-mentioned corbel 210, and the ear walls constrain both sides of the UHPC prefabricated support mounting portion to improve its lateral stability. The provision of the ear walls can reduce the lateral force at the point where the T-shaped connector is plugged into the T-shaped slot.

[0042] Furthermore, the ear walls 230 may also be arranged on the crown beam, that is, on the crown beams on both sides of the T-shaped slot, which can also serve the purpose of constraining both sides of the UHPC prefabricated support installation part.

[0043] Furthermore, considering the error in the spacing between the crown beams on both sides during construction, the longitudinal dimension of the above-mentioned T-shaped slot is significantly larger than the thickness of the cross plate in the above-mentioned T-shaped connector, that is, after the connection is completed, the UHPC prefabricated support has space for longitudinal position adjustment relative to the crown beams on both sides to meet the requirements of installation errors. For example, illustratively, the longitudinal dimension of the T-shaped slot is 1 cm-3 cm larger than the thickness of the cross plate in the T-shaped connector, and during the construction process, the gap between the T-shaped connector and the T-shaped slot is filled by adding a rigid pad. After the rigid pad is filled, an axial force fit is formed between the two ends of the UHPC prefabricated support and the crown beams on both sides, that is, the UHPC prefabricated support exerts its support performance and solves the problem of error between the support length and the spacing between the crown beams on both sides at the construction site.

[0044] Furthermore, considering the error in the relative position of the sockets between the crown beams on both sides during construction, the lateral dimension of the above-mentioned T-shaped slot is significantly larger than the lateral width of the cross plate in the above-mentioned T-shaped connector, that is, after the connection is completed, the UHPC prefabricated support has space for lateral position adaptation relative to the crown beams on both sides to meet the requirements of lateral installation errors. For example, illustratively, the width dimension of the T-shaped slot is 1 cm larger than the thickness of the cross plate in the T-shaped connector. The existence of this adjustment space can be used to assist in regulating the UHPC prefabricated support to be in a vertical assembly relationship with the crown beams on both sides, thereby solving the problem of lateral errors in the sockets in the crown beams on both sides at the construction site.

[0045] Furthermore, appropriate reinforcing ribs are provided on both sides of the socket to improve its rigidity.

[0046] The above-mentioned plug-in connector and socket connector are preferably galvanized for corrosion protection to form a galvanized layer to ensure that they can resist corrosion and prevent moisture erosion during use, thereby extending their service life and improving safety.

[0047] Anchor steel bars 222 are provided on the back of the socket 220 to improve the bonding strength with the crown beam. The lower side of the socket is flush with the corbel platform, and the upper side of the socket is flush with the upper surface of the crown beam.

[0048] Furthermore, the height of the transverse steel plate in the connector is 900 mm and is less than the height of the slot in the socket. The socket and the connector can slide in the vertical direction and adapt to the height of one or both ends by means of rubber bearings (the rubber bearings are generally installed at the bottom of the beam and have a certain allowable range of vertical and horizontal deformation).

[0049] The above-mentioned adjustment method at both ends of the support has a positive significance in the installation stage, which is to ensure the high-precision installation of the support and the crown beams on both sides. After installation, the support can transfer the vertical load to the corbel through the vertical sliding of the end socket and the connector, so it is only subjected to axial tension and compression, optimizing the force structure.

[0050] The distance between the above-mentioned transverse steel plate and the end surface of the UHPC prefabricated support is controlled to be about 100 mm.

[0051] When installing the connection structure, use equipment such as a total station or theodolite to perform precise measurements to determine the location and elevation of the support installation. Use a gantry to lift the UHPC prefabricated support and slowly move it to the predetermined position. Through the fine adjustment function of the gantry, the extended connector of the UHPC prefabricated support is accurately aligned with the top of the socket on the foundation pit wall, with the error controlled at the millimeter level. Then, slowly drop the UHPC prefabricated support, and install the connectors at both ends of the UHPC prefabricated support on the socket. Finally, use bolts to connect the bottom of the UHPC prefabricated support and the rubber bearing to ensure that the centers of the two are aligned. Comprehensively check the stability of the support system, confirm that all connection parts are stable, and the bolt torque meets the standards.

[0052] After the construction of this project is completed, when the connecting structure is dismantled, the last safety check before dismantling is first carried out to confirm the status of the supporting structure and the safety of the surrounding environment. The bolts connecting the bottom of the UHPC prefabricated support and the rubber bearing are removed one by one in diagonal order. After ensuring that all the connecting bolts are loose, the UHPC prefabricated support is then lifted by a gantry, and the UHPC prefabricated support is slowly pulled out of the socket, slowly lifted out of the original position, avoiding obstacles, and smoothly transferred to the designated storage or recycling area to ensure that no collision damage occurs during the process so that the UHPC prefabricated support can continue to be recycled in the next project.

[0053] A method for assembling a UHPC prefabricated support and a crown beam, the construction method comprising the following steps: S1: Forming of the crown beam: Processing the socket, according to the design drawings, machining to form the outline of the socket, and welding anchor steel bars on the back side of the socket to avoid the position of the longitudinal bars of the crown beams on both sides. After the processing is completed, the socket is galvanized as a whole, and the anchor steel bars of the socket are embedded in the casting mold cavity of the crown beams on both sides of the foundation pit, ensuring that the slot in the main body of the socket is located outside the casting template, and the above-mentioned slot is reserved, and the upper side of the slot is flush with the upper surface of the crown beam; The casting formwork for the crown beam and the corbel is set up, the steel cage inside the crown beam is installed, and ordinary concrete is poured at the same time as the crown beam. After curing for 72 hours, the above formwork is removed, and rubber bearings are set above the corbel to facilitate the installation of prefabricated UHPC prefabricated supports. At the same time, ear walls are set to increase lateral support, and you can choose whether to configure them.

[0054] S2: Forming of UHPC prefabricated supports: Processing connectors, welding on longitudinal steel plates to form shear keys, milling grooves to form holes, and welding the longitudinal steel plates vertically to the transverse steel plates to form a whole, forming a T-shaped profile. The connectors are embedded in both ends of the prefabricated UHPC prefabricated support casting template, and the outer ends of the connectors extend outward from the end faces of both ends of the prefabricated UHPC prefabricated support, and are formed by pouring ultra-high performance concrete. The specific prefabrication process is: customize the UHPC prefabricated support casting mold, cut, bend and tie the steel bars into shape, place them in the predetermined position in the mold, fix them with a positioning fixture, make UHPC slurry according to the required UHPC mix ratio, and then pour UHPC. After high-temperature steaming for 24 hours, remove the above-mentioned template, and then let it stand for about 14 days before use.

[0055] S3: Transportation and hoisting. Use hoisting equipment to hoist the UHPC prefabricated support as a whole to the support area of ​​the foundation pit, and then adjust the angle and state of the UHPC prefabricated support through the fine adjustment function of the gantry so that the plug-in is located directly above the socket. Then slowly drop it and try to insert both ends synchronously, and place the rubber support. During the plug-in process, since the length, width and thickness of the transverse steel plate are slightly smaller than the internal space size of the slot in the socket, there is a certain error space, which can make the transverse steel plate easier to embed into the socket; S4: Adjustment and fixation. After plugging in place, measure the verticality between the UHPC prefabricated support and the crown beams on both sides. Select a fixed point on the crown beam as the measurement reference point. Install the total station on a stable bracket to ensure that the instrument is level and stable. Align the total station with the reference point for initial settings. Use the laser ranging and angle measurement functions of the total station to measure multiple points on both sides of the prefabricated support and the crown beam. Directly read and record the verticality data. According to the measurement results, adjust the verticality between the UHPC prefabricated support and the crown beam until the three form an H-shaped support structure. Then use a steel pad to insert it into the gap between the transverse steel plate and the slot. Finally, fix the prefabricated UHPC prefabricated support to the lower corbel through a rubber bearing. Comprehensively check the stability of the support system and confirm that all connection parts are stable and reliable.

[0056] S5: When disassembling, first disassemble the prefabricated UHPC prefabricated support and rubber bearing, then use the gantry to lift the UHPC prefabricated support, slowly pull the UHPC prefabricated support out of the socket, slowly lift it out of the original position, avoid obstacles, and smoothly transfer it to the designated storage or recycling area to ensure that no collision damage occurs during the process, so that the subsequent UHPC prefabricated support can continue to be recycled in the next project.

[0057] Embodiment 2: In the implementation process of this embodiment, the plug-in component is set on the crown beam, and the socket component is set on the UHPC prefabricated support, that is, the positions of the two are interchanged, and the structure after the interchange is as shown in FIG. Figure 6 and Figure 7 ,in Figure 6 The plug-in connector 110 is located at the crown beam, that is, it is fixed at the crown beam by pre-embedding. Figure 7 The sockets 220 shown in the figure are arranged at both ends of the UHPC prefabricated support by pre-embedded manner.

[0058] The structure shown in this embodiment should also be within the protection scope of the present invention.

[0059] Embodiment 3 refer to Figures 8 to 10 This embodiment is developed on the basis of the second embodiment. Specifically, The connector 110 is formed by welding two transverse steel plates 111 and a longitudinal steel plate 112 into a "stem"-shaped profile, and forms a plug-in structure that cooperates with the socket, and further welds triangular ribs at the splicing position of the transverse steel plate and the longitudinal steel plate for reinforcement. At the same time, a shear key 1121 and a long hole 1122 are provided on the longitudinal steel plate 112. The setting of the shear key and the long hole can enhance the bonding force with the UHPC material, and when the installation part is subjected to axial pressure, the shear resistance between the longitudinal steel plate and the UHPC is improved.

[0060] The connector is embedded on the crown beam according to the requirements of the drawings. The embedded connector 110 is located above the corbel 210 and is used to install the above-mentioned UHPC prefabricated support. The sockets 220 are at both ends of the UHPC prefabricated support 100. The sockets are rectangular in structure and have a T-shaped slot 221. The two ends of the above-mentioned UHPC prefabricated support are quickly matched with the crown beam through plug-in fitting. The plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and after the angle is adjusted, it is expanded using a steel pad. At the same time, a rubber bearing is arranged at the mating surface between the mounting portion of the UHPC prefabricated support and the crown beam corbel, which can ensure the stability of the position of the UHPC prefabricated support on the corbel, and can also transfer loads and deformations, reduce shocks and leveling. In other words, through the setting of the rubber bearing, the vertical load and horizontal load borne can be effectively transferred to the corbel, ensuring the overall stability and safety; the rubber bearing has good elasticity and adaptability, and can adapt to the expansion and contraction deformation of the UHPC prefabricated support caused by environmental factors such as temperature and humidity, as well as the deformation caused by other loads, thereby extending the service life of the support.

[0061] Furthermore, considering the error in the distance between the two side capping beams during construction, the longitudinal dimension of the above T-shaped slot is significantly larger than the thickness of the transverse plate in the above "dry"-shaped plug-in member. That is, after the plugging is completed, the UHPC precast support has space for longitudinal position adjustment relative to the two side capping beams to meet the requirements of installation errors. For example, exemplarily, the longitudinal dimension of the T-shaped slot is 1 cm - 3 cm larger than the thickness of the transverse plate in the "dry"-shaped plug-in member. During the construction process, the gap between the "dry"-shaped plug-in member and the T-shaped slot is filled by adding rigid backing plates. After the filling of the rigid backing plates 300, axial force-bearing cooperation is formed between the two ends of the UHPC precast support and the two side capping beams. That is, the UHPC precast support exerts its support performance and solves the problem of the error between the support length and the distance between the two side capping beams at the construction site.

[0062] Furthermore, considering the error in the relative position of the socket members between the two side capping beams during construction, the transverse dimension of the above T-shaped slot is significantly larger than the transverse width of the transverse plate in the above "dry"-shaped plug-in member. That is, after the plugging is completed, the UHPC precast support has space for transverse position adaptation relative to the two side capping beams to meet the requirements of installation transverse errors. For example, exemplarily, the width dimension of the T-shaped slot is 1 cm larger than the thickness of the transverse plate in the "dry"-shaped plug-in member. The existence of this adjustment space can be used to assist in regulating the perpendicular assembly relationship between the UHPC precast support and the two side capping beams, and solves the problem of the error in the transverse direction of the socket members in the two side capping beams at the construction site.

[0063] Furthermore, appropriate reinforcing ribs are provided on both sides of the socket member to improve its stiffness.

[0064] The structure shown in this embodiment should also be within the protection scope of the present invention.

[0065] Embodiment 4 In this embodiment, different from Embodiment 3, the plug-in member is "dry"-shaped and is embedded at both ends of the UHPC precast support. The corresponding socket member is a rectangular structure and is embedded on the outer side of the capping beam. That is, both ends of the above UHPC precast support are plugged and cooperated with the socket members on the capping beam through the "dry"-shaped plug-in members, which is exactly the opposite of the setting in Embodiment 3. Through this plugging structure, the purpose of quick plugging connection can also be achieved.

[0066] Other structures are basically the same as those in Embodiment 1 and will not be elaborated.

[0067] The structure shown in this embodiment should also be within the protection scope of the present invention.

[0068] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the present invention by relevant technical personnel in the field should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A UHPC support and crown beam sliding rail connection structure, comprising a UHPC prefabricated support and a crown beam, It is characterized in that The UHPC prefabricated support is structurally divided into a support body and installation parts located at both ends of the support body. The so-called installation part refers to the part that is assembled and constructed with the crown beam in the foundation pit support. The support body is a UHPC prefabricated component composed of longitudinal reinforcement and UHPC, and its cross-section is I-shaped, rectangular or circular. The crown beam is provided with a corbel, and the crown beam and the installation part are quickly assembled and installed through sockets and connectors.

2. A UHPC support and crown beam slide rail connection structure according to claim 1, It is characterized in that The connector is fixed on the mounting portion. The connector is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long strip hole are provided on the longitudinal steel plate. The socket is pre-buried in the crown beam. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is provided at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

3. A UHPC support and crown beam slide rail connection structure according to claim 1, It is characterized in that The connector is fixed on the crown beam. The connector is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long hole are arranged on the longitudinal steel plate, and the socket is pre-buried in the installation part. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is arranged at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

4. A UHPC support and crown beam slide rail connection structure according to claim 2 or 3, It is characterized in that The longitudinal dimension of the T-shaped slot is significantly larger than the thickness of the transverse steel plate in the above-mentioned T-shaped connector. After the connection is completed, the UHPC prefabricated support has space for longitudinal position adjustment relative to the crown beams on both sides. During the construction process, the gap between the connector and the T-shaped slot is filled by adding a rigid pad, so that the two ends of the UHPC prefabricated support and the crown beams on both sides form an axial force fit.

5. According to claim 1, a UHPC support and crown beam slide rail connection structure, It is characterized in that The connector is fixed on the installation part. The connector is a stem-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long strip hole are arranged on the longitudinal steel plate. The socket is pre-buried in the crown beam. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is arranged at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

6. A UHPC support and crown beam slide rail connection structure according to claim 1, It is characterized in that The connector is fixed on the crown beam. The connector is a stem-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long hole are arranged on the longitudinal steel plate, and the socket is pre-buried in the installation part. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom. After being plugged in place, the UHPC prefabricated support is stabilized under its own weight, and a rubber bearing is arranged at the mating surface between the bottom of the UHPC prefabricated support and the corbel.

7. A UHPC support and crown beam slide rail connection structure according to claim 1, It is characterized in that Ear walls are arranged on both sides of the corbel or the crown beam, and the ear walls constrain both sides of the UHPC prefabricated support installation part.

8. The UHPC support and crown beam slide rail connection structure according to claim 1, It is characterized in that The crown beam can be a reinforced concrete crown beam or a steel structure crown beam.

9. A method for connecting a UHPC support and a crown beam slide rail connection structure, comprising a UHPC prefabricated support and a crown beam, It is characterized in that The UHPC prefabricated support is structurally divided into a support body and installation parts located at both ends of the support body. The so-called installation part refers to the part that is assembled and constructed with the crown beam in the foundation pit support, wherein the support body is a UHPC prefabricated component composed of longitudinal reinforcement and UHPC, and its cross-section is I-shaped, rectangular or circular. A corbel is arranged on the crown beam, and the crown beam and the installation part are quickly assembled and installed through a socket and a plug-in. The plug-in is fixed to the installation part. The plug-in is a T-shaped profile formed by welding a transverse steel plate and a longitudinal steel plate. A shear key and a long strip hole are arranged on the longitudinal steel plate, and the socket is pre-buried in the crown beam. The socket has a T-shaped slot, and the two are connected by a T-shaped plug-in structure. The plug-in direction is from top to bottom, and the following steps are included: S1: Forming of the crown beam: Process the socket and weld the anchor steel bars on the back side of the socket, avoiding the longitudinal bars of the crown beams on both sides. After processing, the socket is galvanized as a whole, and the anchor steel bars of the socket are embedded in the casting mold cavity of the crown beams on both sides of the foundation pit, ensuring that the slot in the main body of the socket is located outside the casting template, and the T-shaped slot is reserved, and the upper side of the T-shaped slot is flush with the upper surface of the crown beam; erect the casting template at the crown beam and the corbel position, install the steel cage inside the crown beam, and cast ordinary concrete at the same time as the crown beam. After curing for 72 hours, remove the casting template, set a rubber bearing above the corbel, and set an ear wall at the same time; S2: Forming of UHPC prefabricated support: Processing connectors, welding on longitudinal steel plates to form shear keys, milling grooves to form holes, welding the longitudinal steel plates vertically to the transverse steel plates to form a T-shaped profile, embedding connectors at both ends of the prefabricated UHPC prefabricated support casting template, and the outer ends of the connectors extend outward from the end faces of both ends of the prefabricated UHPC prefabricated support, using UHPC slurry for casting and high-temperature steam curing for 24 hours, and then removing the mold and curing for 14 days; S3: Transportation and hoisting: Use hoisting equipment to hoist the UHPC prefabricated support as a whole to the area to be supported in the foundation pit, adjust the angle and state of the UHPC prefabricated support so that the plug-in is located directly above the socket, and then slowly drop it, and try to insert both ends of the UHPC prefabricated support synchronously, and place the rubber bearing; S4: Adjustment and fixation. After plugging in place, measure the verticality between the UHPC prefabricated support and the crown beams on both sides. Select a fixed point on the crown beam as the measurement reference point. Install the total station on a stable bracket to ensure that the instrument is level and stable. Align the total station with the reference point for initial settings. Use the laser ranging and angle measurement functions of the total station to measure multiple points on both sides of the prefabricated support and the crown beam. Directly read and record the verticality data. According to the measurement results, adjust the verticality between the UHPC prefabricated support and the crown beam until the three form an H-shaped support structure. Use a steel pad to insert it into the matching gap between the connector and the socket. Fix the UHPC prefabricated support to the lower corbel through the rubber support. Comprehensively check the stability of the support system and confirm that all connection parts are stable and reliable.

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