Foundation pit top UHPC (Ultra High Performance Concrete) blanket assembly structure capable of recovering energy and construction method

Abstract

The invention discloses a foundation pit top UHPC (Ultra High Performance Concrete) blanket splicing structure capable of recovering energy and a construction method, and relates to a bridge deck slab blanket system splicing structure capable of realizing cyclic utilization. The assembly structure comprises a foundation pit support, a steel protection plate, a crown beam and a UHPC prefabricated bridge deck, a plurality of pressure power generation modules are arranged on the back face of the UHPC prefabricated bridge deck and arranged in the space between the UHPC prefabricated bridge deck and the foundation pit support, and when a vehicle presses the UHPC prefabricated bridge deck downwards, the pressure power generation modules generate power. The pressure power generation module is connected with the energy storage module through a cable to achieve storage of electric energy. According to the design of the energy recovery device, dependence on external energy is reduced, the energy consumption cost of a construction project is reduced, and the concept of green construction is deeply practiced.

Description

Technical Field

[0001] The invention relates to an energy-recoverable UHPC blanket assembly structure on the top of a foundation pit and a method thereof, and belongs to the field of foundation pit construction engineering. Background Art

[0002] At present, with the acceleration of urban construction, foundation pit construction sites are often located in city centers or busy traffic areas. Traditional large-area fencing measures have undoubtedly had a serious impact on surrounding traffic and aggravated congestion. It is urgent to improve traffic conditions by changing construction methods.

[0003] Traditionally, the road surface passages on the top of the foundation pit mostly use cast-in-place concrete structures with a small width, which are passages for construction personnel. Although this practice ensures the structural strength to a certain extent, the problems faced after the construction cannot be ignored. First, the demolition of these huge cast-in-place structures is not only time-consuming and labor-intensive, but also generates a large amount of construction waste, which increases the burden on the urban waste disposal system and is not conducive to environmental protection. Secondly, the use of a large amount of materials and the energy consumption in the waste disposal process violate the principle of sustainable development.

[0004] During the foundation pit construction process, excavation is one of the key links. Frequent earthwork transportation requires the closed structure on the top of the foundation pit to be highly flexible and operable. Traditional foundation pits have no covering structure on the top and can be excavated at any time. Therefore, it is required to introduce a covering bridge deck structure that can be opened and closed at any time into the foundation pit construction project, so as to complete the rapid opening and closing and disassembly of the covering structure to respond to the needs of excavation.

[0005] Nowadays, energy conservation, emission reduction and green development have become the development consensus of all walks of life. The present invention makes full use of the vibration energy generated by the bridge deck covering system on the top of the foundation pit during the passage of people and vehicles, and converts the mechanical energy that would otherwise be wasted into electrical energy through the built-in high-sensitivity vibration energy collection device.

[0006] Therefore, it is necessary to develop a lightweight, high-strength, recyclable foundation pit top covering assembly structure and corresponding construction methods. Summary of the invention

[0007] Purpose of the invention: The purpose of the present invention is to provide a UHPC blanket assembly structure and construction method for the top of a foundation pit that can recover energy. It is an assembly structure of a bridge deck blanket system that can be disassembled and opened and closed at any time and can be recycled. At the same time, it can also use the vibration generated by the passage of people and vehicles above the bridge deck to recover energy, thereby solving the drawbacks of existing blanket structures.

[0008] The technical solution adopted by the present invention to solve the technical problem is: A UHPC covering assembly structure on the top of a foundation pit with energy recovery, comprising a foundation pit support, a steel guard plate, a crown beam and a UHPC prefabricated bridge deck, wherein the foundation pit support, the steel guard plate and the crown beam constitute the basic structure of the foundation pit support, and a bridge deck assembled from multiple UHPC prefabricated bridge decks is fixedly installed above the foundation pit support, characterized in that: the UHPC prefabricated bridge deck is a prefabricated plate made of UHPC material, the aspect ratio of the UHPC prefabricated bridge deck is at least 5:1 and the length spans at least two foundation pit supports, the connecting sections at both ends of the UHPC prefabricated bridge deck are mechanically connected by tongue-and-groove fittings and high-strength bolts to form a quick assembly structure; multiple pressure power generation modules are arranged on the back of the UHPC prefabricated bridge deck, The pressure power generation module is arranged in the space between the UHPC prefabricated bridge deck and the foundation pit support. When the vehicle presses down the UHPC prefabricated bridge deck and causes the pressure power generation module to generate electricity, the pressure power generation module is connected to the energy storage module through a cable to store electrical energy, and a plurality of bridge deck fixings are fixed on the back of the UHPC prefabricated bridge deck. The bridge deck fixings are U-shaped and wrap the foundation pit support, and a spring assembly is arranged in the space between the bridge deck fixings and the foundation pit support to improve the stability of the UHPC prefabricated bridge deck; above the UHPC prefabricated bridge deck is an asphalt layer, which avoids the connecting sections at both ends of the UHPC prefabricated bridge deck, and a channel steel assembly is arranged there, and the design height of the channel steel assembly is consistent with the thickness of the asphalt pavement layer.

[0009] Furthermore, the tongue-and-groove fit means that, in the two end connection sections of the UHPC prefabricated bridge deck, a bolt hole is provided at one connection section, and a high-strength bolt is provided on the other connection section, through which the high-strength bolt is inserted into the bolt hole and fastened with a nut.

[0010] Furthermore, the tongue-and-groove fit means that threaded bolt sleeves are provided in the connection sections at both ends of the UHPC prefabricated bridge deck, and the two bolt sleeves are precisely aligned and then tightened and fixed using high-strength bolts.

[0011] Furthermore, the bottom and side surfaces of the connecting section are provided with steel plates, the thickness of the bottom steel plate is 5-8 mm, and the thickness of the side steel plate is 1-3 mm.

[0012] Furthermore, the edge of the connection section is configured as a serrated edge, and the two UHPC prefabricated bridge panels are engaged with each other through the serrated connection section, thereby increasing the stability of the overall connection structure.

[0013] Furthermore, a buffer pressure plate is arranged and fixedly installed between the UHPC prefabricated bridge deck and the pressure power generation module. The UHPC prefabricated bridge deck applies downward pressure to the buffer pressure plate, and the multiple pressure power generation modules form a compression stroke in the vertical direction and generate electricity.

[0014] Furthermore, the bridge deck fixing member is a metal component with a U-shaped profile, and the bridge deck fixing member is mechanically connected to the buffer pressure plate or the UHPC prefabricated bridge deck.

[0015] Furthermore, the foundation pit support is a reinforced concrete support or a steel support.

[0016] Furthermore, the pressure power generation module includes a housing, a cover plate, a pressure cup, an electromagnetic induction coil, and a reset spring. The cover plate is tightly combined with the housing via fixing screws, is the main part that directly bears the pressure, and is the key interface that bears the dynamic load. The pressure power generation module is a linear generator, and generates current when the pressure cup and the electromagnetic induction coil slide relative to each other in the axial direction.

[0017] A construction method for a UHPC blanket assembly structure on the top of a foundation pit capable of recovering energy, characterized in that the following steps are performed in sequence: S1: Construct steel sheet piles for the foundation pit, and construct the crown beam and foundation pit support to form the basic framework of the foundation pit enclosure, which is ready for installation and use; S2: Factory prefabrication of UHPC prefabricated bridge deck: According to the design drawings, the side steel plates and the bottom steel plates are processed, wherein high-strength bolts are welded in the bottom steel plate of the lower connecting section to form a whole, and bolt sleeves are welded in the bottom steel plate of the upper connecting section to form a whole; and a forming mold is set up, in which the steel bars are cut, bent and tied to form a steel mesh, the steel mesh is placed in a predetermined position in the mold, fixed with a positioning fixture, and then the UHPC slurry is poured. After pouring, it is steamed at high temperature for 24 hours, and the forming template and the side steel plates are removed to form the UHPC prefabricated bridge deck for standby use; S3: Transportation and hoisting. The hoisting equipment hoists the UHPC prefabricated bridge deck as a whole to the area to be paved in the foundation pit. Then, the pressure power generation module, bridge deck fixings and spring components are installed on the foundation pit support. The UHPC prefabricated bridge deck is hoisted and installed above the corresponding foundation pit support. During the installation process, a total station or theodolite is used for precise measurement to ensure that the positioning accuracy of the UHPC prefabricated bridge deck support assembly matches the expected elevation. High-strength bolts are used to accurately align the two ends of the UHPC prefabricated bridge deck, and the error is controlled at the millimeter level. After the nesting is completed, the torque wrench applies a pre-tightening force to the nut to complete the mechanical connection. After the installation is completed, the pressure power generation module and the energy storage module are quickly connected using a cable; S4: Bridge deck paving. After the UHPC prefabricated bridge deck is assembled, the bridge deck is paved. First, the channel steel assembly is used to cover the top of the connection section to avoid the impact on the connection section when laying asphalt. When the front panel needs to be disassembled, it is only necessary to simply separate the channel steel section. After the operation channel steel assembly is covered, avoid the connection section channel steel to lay asphalt, and the asphalt height is consistent with the channel steel assembly; S5: Disassembly and recycling. After the project construction is completed, the process of disassembling the connection structure is turned to. The first step is to conduct a comprehensive safety review of the entire assembled structure, aiming to fully verify the integrity of the assembled structure and the unobstructed state of the surrounding environment, confirm that there are no safety hazards, and ensure that the dismantling operation is carried out under the premise of absolute safety; The dismantling operation first separated the channel steel assembly from the bridge deck connection section, and gradually dismantled all the bolt connections assembled on the UHPC prefabricated bridge deck connection section. The UHPC prefabricated bridge deck was smoothly lifted using the precise control function of the gantry crane, and through delicate operations, the bolt sleeves of the upper connection section were smoothly separated from the high-strength bolts of the lower connection section.

[0018] The beneficial effects of the present invention are: (1) The foundation pit top covering scheme proposed in the present invention constructs a stable and efficient closed system in a limited space, and can be easily and quickly disassembled and assembled for construction, effectively reducing the occupation of surrounding roads by construction and maintaining the necessary traffic capacity. This not only alleviates the traffic pressure during the construction period, but also reduces the interference with the daily travel of citizens, reflecting the humanization and refinement of urban construction management.

[0019] (2) The present invention innovatively utilizes the excellent performance of UHPC materials and adopts prefabricated parts, including its excellent compressive, tensile and flexural strength, which far exceeds that of traditional concrete, thereby achieving a significant reduction in the cross-section of the bridge deck structure and simultaneously improving construction efficiency and material utilization. At the same time, the outstanding corrosion resistance, high wear resistance and excellent seismic resistance exhibited by UHPC materials ensure the long-term stability and low maintenance requirements of the covering structure in complex environments, which together contribute to a significant increase in the life of the components and a significant reduction in maintenance costs, giving the temporary covering structure unprecedented durability and economic benefits.

[0020] (3) The present invention creatively introduces a detachable UHPC prefabricated bridge deck covering structure into the foundation pit construction scene, achieving a major breakthrough in effectively maintaining the smoothness of on-site traffic without affecting the progress of the project. Taking advantage of the high strength and lightweight characteristics of UHPC materials, the customized bridge deck can be quickly installed above the foundation pit, immediately forming a stable temporary road surface, which not only provides a safe and convenient passage for construction personnel and machinery and equipment, but also greatly alleviates the traffic congestion problem during construction and minimizes the interference and impact on surrounding traffic flow lines.

[0021] (4) The design of the bridge deck that can be opened at any time proposed in the present invention can quickly open the designated area while ensuring safety, facilitating excavation operations, and then quickly close it to restore the closed state, greatly improving the flexibility and efficiency of construction.

[0022] (5) The energy recovery device in the present invention not only reduces the dependence on external energy and the energy consumption cost of the construction project, but also deeply practices the concept of green construction. The detachable connection structure is generally used for short-term or temporary projects that need to control traffic flow. Display screens can be set up on the roadside to display traffic information, road condition prompts, etc. in real time. By integrating environmentally friendly technology into infrastructure construction, it demonstrates the perfect combination of science and technology and environmental protection, and leads the development direction of future foundation pit engineering technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the overall construction effect of Example 1; Figure 2 It is a top view of the assembled structure of the first embodiment; Figure 3 It is a bottom view of the assembled structure of the first embodiment; Figure 4 This is a schematic diagram of the connection of the side and bottom steel plates of Example 1; Figure 5 It is a side view of the overall structure of the first embodiment; Figure 6 This is a schematic diagram of a pressure power generation module of Example 1; Figure 7 This is a diagram of the connection between the bridge deck fixing member and the board of the first embodiment; Figure 8 This is a diagram of the bridge deck fixing and support connection of the first embodiment; Fig. 9 This is a schematic diagram of the overall construction effect of Example 2; Fig.10 This is a schematic diagram of the X-axis direction of the second embodiment; Fig.11 It is a schematic diagram of the Y-axis direction of the second embodiment; Fig.12 This is a connection diagram of Embodiment 3; In the figure: 100 UHPC precast bridge deck, 110 foundation pit support, 120 connecting section, 121 high-strength bolt, 122 bolt hole, 123 bottom steel plate, 124 side steel plate, 1241 slot type joint, 1242 steel plate connection fixing buckle, 130 steel guard plate, 140 crown beam, 200 energy recovery device, 210 pressure power generation module, 220 bridge deck fixing part, 230 spring assembly, 240 cable, 250 energy storage module, 260 buffer pressure plate, 211 housing, 212 cover plate, 213 pressure cup, 214 electromagnetic induction coil, 215 return spring. DETAILED DESCRIPTION

[0024] This embodiment first describes a detachable assembly structure between bridge panels, which enables each prefabricated unit to be quickly and accurately unfolded and locked in place on site, greatly improving assembly efficiency. This design allows the bridge panels to remain compact during transportation, making it easy to pass through narrow or restricted transportation routes, and then be easily opened and installed after arriving at the destination, which perfectly meets the needs of rapid installation and temporary or permanent bridge projects.

[0025] At the same time, when the bridge is opened to traffic after the laying is completed, the vibration of the bridge deck can be used to realize the demand for energy recovery, reducing the dependence on external energy, reducing the energy consumption cost of the construction project, and deepening the practice of the green construction concept. By integrating environmentally friendly technology into infrastructure construction, it demonstrates the perfect combination of technology and environmental protection, and leads the development direction of future foundation pit engineering technology.

[0026] 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.

[0027] Embodiment 1: refer to Figures 1 to 8 As shown in the attached figure, the UHPC pavement assembly structure on the top of the foundation pit includes a foundation pit support 110, a steel guard plate 130, a crown beam 140, and a UHPC prefabricated bridge deck 100, wherein: Figure 1 In the figure, steel guard plates 130 are located on both sides of the foundation pit. The steel guard plates 130 support the soil on both sides (not shown in the figure). The crown beam 140 surrounds the top of the upper end of the foundation pit steel guard plates and supports the steel guard plates laterally. The two ends of the foundation pit support 110 are fixedly connected to the crown beams on both sides to form a rigid support.

[0028] Furthermore, the above-mentioned foundation pit support 110 can be a reinforced concrete support or a steel support. As long as it plays a supporting role, it is within the protection scope of the present invention.

[0029] The above-mentioned UHPC prefabricated bridge deck 100 is prefabricated in a factory using UHPC materials, and the two ends are fastened with high-strength bolts through the tongue-and-groove design that engages with each other, thereby achieving fast and efficient installation and disassembly of the bridge deck.

[0030] The assembled structure adopts a tongue-and-groove design in which the ends of the bridge deck are overlapped and assembled. Specifically, a connection section 120 is provided at both ends of the UHPC prefabricated bridge deck 100, with a tongue-and-groove design, and the two connection sections are connected by high-strength bolts. Figure 2A bolt hole 122 is set at one of the connecting sections 120, and a high-strength bolt 121 is set on the other connecting section. The high-strength bolt 121 can be inserted into the above-mentioned bolt hole 122 to accurately fit, and is fastened with a nut to complete the assembly.

[0031] Furthermore, in order to enhance the mechanical properties of the connection portion, the edge of the connection section may be set to a serrated edge, and the two bridge decks may engage with each other through the serrated connection section, thereby increasing the stability of the overall connection structure.

[0032] Furthermore, steel plates are provided on the bottom and sides of the upper and lower connecting sections. The thickness of the bottom steel plate 123 can be set to 5-8 mm to weld high-strength bolts and bolt sleeves so that the two can be accurately positioned to avoid being affected by the shrinkage creep of UHPC, which causes the high-strength bolts and bolt sleeves to be unable to align. The thickness of the side steel plate 124 can be set to 1-3 mm to support the bottom steel plate of the support and can also serve as a mold for the UHPC bridge deck during casting.

[0033] Further, refer to Figure 4 The side steel plate 124 and the bottom steel plate 123 can be connected by a slot joint 1241 or a connecting buckle 1242 can be set between the two to make them removable, and a non-slip coating with a low friction coefficient is used between the side steel plate and the UHPC, such as a polytetrafluoroethylene (PTFE) coating or other specially designed lubricating coating; when the maintenance is completed, the side steel plate can be removed and continued to be used in the subsequent bridge deck casting, which greatly improves the material utilization rate Furthermore, the lower connecting section is fixed with high-strength bolts 121 by welding through the bottom steel plate, and the upper connecting section is fixed with bolt sleeves by welding through the bottom steel plate to form the above-mentioned bolt holes. The presence of the bolt sleeves can enhance the strength of the bolt holes. Taking into account the errors occurring during prefabrication and construction, the inner diameter of the bolt sleeves should be slightly larger than the diameter of the high-strength bolts 121 to ensure precise alignment during installation and to ensure that slight deformation of the high-strength bolts will not affect the disassembly between the bridge panels during use.

[0034] Furthermore, the energy recovery device 200 includes a pressure power generation module 210 , a bridge deck fixing member 220 for stabilizing the covering structure, a spring assembly 230 , a cable 240 , and an energy storage module 250 .

[0035] Further, the pressure power generation module 210 is arranged above the foundation pit support 110, and the number is multiple, and the spring assembly 230 is arranged below the foundation pit support 110. The lower end of the above-mentioned pressure power generation module is fixedly connected to the foundation pit support, and the upper end is fixedly connected to the back of the UHPC prefabricated bridge deck 100. It is easy to understand that when a downward pressure is applied to the above-mentioned UHPC prefabricated bridge deck 100, the above-mentioned multiple pressure power generation modules form a compression stroke in the vertical direction and generate electricity. In order to improve the stability of the UHPC prefabricated bridge deck 100, multiple U-shaped bridge deck fixings 220 are fixedly installed on the back of the UHPC prefabricated bridge deck 100. Specifically, the bridge deck fixing 220 is fixedly connected to the UHPC prefabricated bridge deck 100 by screws, and the bridge deck fixing 220 wraps the above-mentioned foundation pit support from bottom to top, and a spring is installed in the U-shaped space of the bridge deck fixing, that is, the spring is installed between the top of the bridge deck fixing and the foundation pit support 110. This structure ensures the stable connection of the upper and lower components.

[0036] One step forward, reference Figure 5 The pressure power generation module 210 has a fine internal structure, including a housing 211, a cover plate 212, a pressure cup 213, an electromagnetic induction coil 214, and a return spring 215. The cover plate is tightly combined with the housing via fixing screws, and is the main part that directly bears the pressure, becoming a key interface for bearing dynamic loads. The pressure power generation module is a linear generator. When the pressure cup 213 and the electromagnetic induction coil 214 slide relative to each other in a linear manner in the axial direction, current will be generated and stored in the energy storage module 250 through the cable 240.

[0037] The power generation principle of the pressure power generation module 210 is that during operation, when a vehicle passes over the cover plate 212 of the pressure power generation module, the bridge deck vibrates due to the effect of gravity, so that the cover plate drives the pressure cup 213 connected to it to move along a vertical path, thereby achieving a height stroke and cutting the magnetic flux lines in the magnetic field. The closed electromagnetic coil generates direct current through the change of electromagnetic induction magnetic flux, thereby realizing the conversion of mechanical energy into electrical energy.

[0038] Furthermore, while achieving the effect of a DC generator, the final downward pressing gravity leaves the cover plate, and the downward pressing process ends. Under the action of the reset spring, the pressure cup moves upward to achieve reset, while continuing to pass through the electromagnetic coil, and then circulates to achieve the electromagnetic induction effect. The DC generator generates electricity again, and the additional recovery potential energy is used to trigger the electromagnetic induction process again, realizing two-way energy recovery, and further increasing the power generation efficiency by using the differential design.

[0039] As a step forward, springs and bridge deck fixings are arranged under the support. According to the principle of mechanical properties, it can not only strengthen the overall covering support system, but also effectively amplify the vibration effect by increasing the vibration stroke on the overall height, resulting in more obvious vibration and deformation of the bridge deck, accelerating the accumulation and conversion of energy, and collecting energy more quickly and efficiently.

[0040] Furthermore, the introduction of the above-mentioned cables ensures an efficient and reliable connection between the pressure power generation module and the energy storage module. The use of bending-resistant, highly tough, and highly conductive carbon fiber composite materials or liquid metal wire mesh ensures efficient and safe energy transmission, thereby ensuring that electrical energy can still be transmitted stably even when the bridge deck continues to vibrate frequently.

[0041] Furthermore, the energy storage module includes an energy storage battery, and the cable transfers the collected electrical energy to the energy storage battery for storage. In order to improve energy utilization efficiency and response speed, the instant response advantage of the supercapacitor and the long-term energy storage characteristics of the large-capacity lithium battery are combined to quickly respond to load demand and efficiently store long-term accumulated electrical energy for use at night or during low traffic periods.

[0042] Furthermore, the design of the energy recovery device fully considers the challenges of extreme weather conditions and long-term outdoor deployment, selects weather-resistant materials, and incorporates overheating and overvoltage protection mechanisms to ensure long-term stable operation.

[0043] Furthermore, during pre-assembly of the components, the pressure power generation module and the cable conductive interface are pre-assembled for functional verification; the energy storage module is integrated in a casing with excellent protective performance and preliminary debugging is carried out; finally, the pre-assembled components are integrated and comprehensive safety and functional testing is carried out to verify the overall stability of the system and the consistency of the power output, ensuring that the modules work together smoothly.

[0044] Furthermore, after the above-mentioned UHPC prefabricated bridge deck 100 is paved, an 8-12cm asphalt layer can be paved, which can significantly enhance the bearing capacity and durability index of the bridge, and significantly improve the road safety and driving comfort by effectively dispersing the transmitted load and providing excellent waterproof and anti-corrosion performance, while ensuring the structural adaptability under complex and changing climate conditions. Although the initial construction cost has increased, in the long run, the overall cost-effectiveness has been positively improved due to the reduced maintenance needs and frequency.

[0045] Furthermore, on the asphalt foundation, an equal-height channel steel component is implanted directly above each connecting section, and its design height is consistent with the asphalt pavement layer. The shape of the channel steel can be rectangular, inverted U-shaped or similar U-shaped, ensuring that the connecting part is free from asphalt coverage, so that when disassembly work is required, it is only necessary to simply lift the channel steel section to perform the operation without obstacles; such a design not only provides the necessary bearing capacity and facilitates the dispersion of the bridge deck load, but also effectively prevents rainwater and other corrosive substances from penetrating between the bridge deck and the connecting structure, thereby extending the service life of the bridge deck and reducing the frequency of maintenance.

[0046] During the installation of the connection structure, the energy recovery device is first set at the fixed position of the foundation pit support in the preparation stage, and the communication circuit connects all the power generation modules and finally leads to the energy storage module. Use equipment such as total stations or theodolites to perform precise measurements to ensure that the positioning accuracy of the support components matches the expected elevation. Use the gantry to lift the UHPC prefabricated bridge panel and slowly move it to the predetermined position. Through the fine adjustment function of the gantry, slowly align the bolt sleeve in the upper connection section of the UHPC prefabricated bridge panel with the high-strength bolt in the lower connection section of another UHPC prefabricated bridge panel, and control the error within the millimeter level. Then, the UHPC prefabricated bridge panel is smoothly lowered, so that the bolt sleeve is aligned with the high-strength bolt below and accurately nested. Then, use an electronic torque wrench to apply pre-tightening force to the nuts. Finally, a comprehensive inspection of the stability of the assembled structure is carried out to confirm that all connection parts are stable and the bolt torque meets the standard.

[0047] After the UHPC prefabricated bridge deck is assembled, the bridge deck is paved. First, the channel steel assembly is used to cover the top of the connection section to avoid the impact on the connection section when laying asphalt. After the channel steel assembly is covered, the asphalt is laid avoiding the channel steel of the connection section, and the height is consistent with the channel steel assembly.

[0048] After the construction of the project is completed, it enters the stage of dismantling the connection structure. The first task is to conduct a comprehensive final safety audit of the supporting structure to verify its current status and the surrounding environment. After confirmation, the channel steel components are first separated, and then all the connecting bolts of the UHPC prefabricated bridge deck connection section are removed in sequence. It is necessary to ensure that each bolt is fully loosened. Then, the UHPC prefabricated bridge deck is carefully lifted with a gantry, and the bolt sleeve in the upper connection section is slowly separated from the high-strength bolt of the lower connection section. After that, avoid obstacles and safely transfer the UHPC prefabricated bridge deck to a pre-planned storage or recycling area. The entire transfer process requires special attention to prevent any possible collision and damage to ensure the integrity of the UHPC prefabricated bridge deck, thereby providing UHPC bridge decks that can be used in a circular economy for subsequent projects.

[0049] A method for assembling an openable and energy-recoverable UHPC prefabricated bridge deck comprises the following steps: S1: Construct steel sheet piles for the foundation pit, and construct the crown beam and foundation pit support to form the basic framework of the foundation pit enclosure.

[0050] S2: Manufacturing of UHPC prefabricated bridge deck: According to the design drawings, the side steel plates and the bottom steel plates are processed and spliced ​​together through plug-in seams to facilitate disassembly after the bridge deck is formed; high-strength bolts are welded in the bottom steel plate of the lower connecting section to form a whole, and bolt sleeves are welded in the bottom steel plate of the upper connecting section to form a whole; at this time, the steel plate serves as the end mold of the UHPC prefabricated bridge deck connecting section, and the UHPC prefabricated bridge deck casting mold is customized according to the design drawings, the steel bars are cut, bent and tied to form, placed in the predetermined position in the mold, fixed with a positioning fixture, and UHPC is manufactured according to the required UHPC mix ratio. Subsequently, UHPC is cast, and after high-temperature steaming for 24 hours, the above-mentioned templates and side steel plates are removed. After subsequent static curing for about 14 days, it can be used to form the above-mentioned UHPC prefabricated bridge deck.

[0051] S3: Transportation and hoisting. The hoisting equipment hoists the UHPC prefabricated bridge deck as a whole to the area to be paved in the foundation pit. First, the energy recovery device is fixedly set in the middle position of the surface of the lower connection section of the UHPC bridge deck. The communication circuit can be assembled after the installation of the UHPC bridge deck is completed. In this process, the total station or theodolite and other equipment are used for precise measurement. The UHPC prefabricated bridge deck is hoisted by the gantry and slowly moved to the predetermined position to ensure that the positioning accuracy of the prefabricated bridge deck matches the expected elevation. Through the fine adjustment function of the gantry, the bolt sleeve in the upper connection section of the UHPC prefabricated bridge deck is slowly aligned with the high-strength bolt in the lower connection section of another UHPC prefabricated bridge deck, and the error is controlled at the millimeter level. Then the UHPC prefabricated bridge deck is smoothly lowered, so that the bolt sleeve is aligned with the high-strength bolt below and accurately nested. During the nesting process, since the inner diameter of the bolt sleeve is slightly larger than the diameter of the high-strength bolt, there is a certain error space, which can make the whole process more efficient; after the nesting is completed, the electronic torque wrench is used to apply pre-tightening force to the nut. After the bridge deck is connected, bolts are used to fix the bridge deck fixings to the lower side of the bridge deck to ensure that the energy recovery device can operate normally when driving on the bridge deck. Finally, a comprehensive inspection of the stability of the assembled structure is conducted to confirm that all connection parts are stable and the bolt torque meets the standard.

[0052] S4: Bridge deck paving. After the UHPC prefabricated bridge deck is assembled, the bridge deck is paved. First, the channel steel assembly is used to cover the top of the connection section to avoid the impact on the connection section when laying asphalt. When the front panel needs to be removed, it is only necessary to simply separate the channel steel section; after the operation channel steel assembly is covered, the asphalt is laid avoiding the connection section channel steel, and the height is consistent with the channel steel assembly, which significantly enhances the bearing capacity and durability of the bridge.

[0053] S5: Disassembly and recycling. After the project construction is completed, the process of disassembling the connection structure is turned to. The first step is to conduct a comprehensive safety review of the entire assembled structure, aiming to fully verify the integrity of the assembled structure and the unobstructed state of the surrounding environment, confirm that there are no safety hazards, and ensure that the dismantling operation is carried out under the premise of absolute safety.

[0054] The disassembly operation first separated the channel steel assembly from the bridge deck connection section, and then, according to the established procedures, gradually disassembled all the bolt connections assembled in the UHPC prefabricated bridge deck connection section, with special emphasis on confirming that the bolts were completely loose one by one to avoid any structural damage that might be caused by forced disassembly. The UHPC prefabricated bridge deck was smoothly raised using the precise control function of the gantry, and the bolt sleeves of the upper connection section were smoothly separated from the high-strength bolts of the lower connection section through delicate operations.

[0055] After successful dismantling, operators need to avoid various obstacles on site and use professional equipment to smoothly transfer the UHPC prefabricated bridge deck to the pre-planned storage or recycling area; the entire process must prevent any damage to the bridge deck caused by collision or improper handling, ensure the high quality of UHPC materials is preserved, supply recyclable bridge decks for subsequent construction projects, and implement green and environmentally friendly construction concepts.

[0056] Embodiment 2: refer to Figures 9 to 11 During the implementation of this embodiment, the UHPC prefabricated bridge deck does not directly contact the pressure power generation module in the energy recovery device. A buffer pressure plate 260 is set between the two. When driving above the bridge deck, the buffer pressure plate is first subjected to pressure, which can be transmitted to the pressure power generation module directly below. At the same time, it can act as a buffer, so that the nearby pressure power generation modules are also subjected to vertical downward pressure, which can improve the energy recovery efficiency and enable multiple pressure power generation modules to work at the same time. In addition, by setting a buffer pressure plate, the force-bearing area on the lower side of the bridge deck can be increased, and the service life of the bridge deck can be increased. Other structures are the same as those in Example 1 and will not be repeated here.

[0057] It is easy to understand that when a downward pressure is applied to the buffer pressure plate 260, the multiple pressure power generation modules form a compression stroke in the vertical direction and generate electricity. The bridge deck fixing member is connected to the bridge deck above and to the spring below, acting as a bridge between the bridge deck and the spring, ensuring a stable connection between the upper and lower components.

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

[0059] Embodiment three: refer to Fig.12During the implementation of this embodiment, the upper and lower connecting sections of the UHPC prefabricated bridge deck are welded with threaded bolt sleeves. After the two UHPC bridge decks are accurately aligned according to the bolt sleeves, they are tightened and fixed with high-strength bolts; the high-strength bolts of the lower connecting section are replaced with bolt sleeves. Figure 6 , Figure 6 The bolt sleeve 122 shown is welded to the bottom steel plate 123 of the lower connecting section. The other structures are the same as those in the first embodiment and will not be described in detail.

[0060] The structure shown in this embodiment should also be within the protection scope of the present invention.

Claims

1. A UHPC covered assembly structure on the top of a foundation pit that can recycle energy, comprising a foundation pit support, a steel guard plate, a crown beam and a UHPC prefabricated bridge deck, wherein the foundation pit support, the steel guard plate and the crown beam constitute the basic structure of the foundation pit support, and a bridge deck assembled from multiple UHPC prefabricated bridge decks is fixedly installed above the foundation pit support, characterized in that: The UHPC prefabricated bridge deck is a prefabricated plate made of UHPC material. The aspect ratio of the UHPC prefabricated bridge deck is at least 5:1 and the length at least spans two foundation pit supports. The connecting sections at both ends of the UHPC prefabricated bridge deck are mechanically connected by tongue-and-groove fit and high-strength bolts to form a quick assembly structure. A plurality of pressure power generation modules are arranged on the back of the UHPC prefabricated bridge deck. The pressure power generation modules are arranged in the space between the UHPC prefabricated bridge deck and the foundation pit support. When the vehicle presses down on the UHPC prefabricated bridge deck and causes the pressure power generation modules to Power generation, the pressure power generation module is connected to the energy storage module through a cable to realize the storage of electric energy, and a plurality of bridge deck fixings are fixed on the back of the UHPC prefabricated bridge deck, the bridge deck fixings are U-shaped and wrap the foundation pit support, and a spring assembly is arranged in the space between the bridge deck fixings and the foundation pit support to improve the stability of the UHPC prefabricated bridge deck; above the UHPC prefabricated bridge deck is an asphalt layer, the asphalt layer avoids the connecting sections at both ends of the UHPC prefabricated bridge deck, and a channel steel assembly is arranged there, and the design height of the channel steel assembly is consistent with the thickness of the asphalt pavement layer.

2. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: The tongue-and-groove fit means that, in the two end connection sections of the UHPC prefabricated bridge deck, a bolt hole is provided at one connection section, and a high-strength bolt is provided on the other connection section, through which the high-strength bolt is inserted into the bolt hole and fastened with a nut.

3. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: The tongue-and-groove fit means that threaded bolt sleeves are provided in the connection sections at both ends of the UHPC prefabricated bridge deck, and the two bolt sleeves are precisely aligned and then tightened and fixed with high-strength bolts.

4. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 2 or 3, characterized in that: The bottom and side surfaces of the connecting section are provided with steel plates, the thickness of the bottom steel plate is 5-8 mm, and the thickness of the side steel plate is 1-3 mm.

5. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: The edge of the connection section is configured as a serrated edge, and the two UHPC prefabricated bridge panels are engaged with each other through the serrated connection section, thereby increasing the stability of the overall connection structure.

6. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: A buffer pressure plate is arranged and fixedly installed between the UHPC prefabricated bridge deck and the pressure power generation module. The UHPC prefabricated bridge deck applies downward pressure to the buffer pressure plate, and a plurality of pressure power generation modules form a compression stroke in the vertical direction and generate electricity.

7. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 6 is characterized in that: The bridge deck fixing member is a metal component with a U-shaped profile, and the bridge deck fixing member is mechanically connected to the buffer pressure plate or the UHPC prefabricated bridge deck.

8. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: The foundation pit support is a reinforced concrete support or a steel support.

9. The UHPC blanket assembly structure for the top of a foundation pit capable of recovering energy according to claim 1 is characterized in that: The pressure power generation module includes an outer shell, a cover plate, a pressure cup, an electromagnetic induction coil, and a reset spring, wherein the cover plate is tightly combined with the outer shell via fixing screws, is the main part that directly bears the pressure, and is the key interface for bearing dynamic loads. The pressure power generation module is a linear generator, which generates current when the pressure cup and the electromagnetic induction coil slide relative to each other in the axial direction.

10. A construction method for a UHPC blanket assembly structure on the top of a foundation pit that can recover energy, characterized in that: Follow these steps in order: S1: Construct steel sheet piles for the foundation pit, and construct the crown beam and foundation pit support to form the basic framework of the foundation pit enclosure, which is ready for installation and use; S2: Factory prefabrication of UHPC prefabricated bridge deck: According to the design drawings, the side steel plates and the bottom steel plates are processed, wherein high-strength bolts are welded in the bottom steel plate of the lower connecting section to form a whole, and bolt sleeves are welded in the bottom steel plate of the upper connecting section to form a whole; and a forming mold is set up, in which the steel bars are cut, bent and tied to form a steel mesh, the steel mesh is placed in a predetermined position in the mold, fixed with a positioning fixture, and then the UHPC slurry is poured. After pouring, it is steamed at high temperature for 24 hours, and the forming template and the side steel plates are removed to form the UHPC prefabricated bridge deck for standby use; S3: Transportation and hoisting. The hoisting equipment hoists the UHPC prefabricated bridge deck as a whole to the area to be paved in the foundation pit. Then, the pressure power generation module, bridge deck fixings and spring components are installed on the foundation pit support. The UHPC prefabricated bridge deck is hoisted and installed above the corresponding foundation pit support. During the installation process, a total station or theodolite is used for precise measurement to ensure that the positioning accuracy of the UHPC prefabricated bridge deck support assembly matches the expected elevation. High-strength bolts are used to accurately align the two ends of the UHPC prefabricated bridge deck, and the error is controlled at the millimeter level. After the nesting is completed, the torque wrench applies a pre-tightening force to the nut to complete the mechanical connection. After the installation is completed, the pressure power generation module and the energy storage module are quickly connected using a cable; S4: Bridge deck paving. After the UHPC prefabricated bridge deck is assembled, the bridge deck is paved. First, the channel steel assembly is used to cover the top of the connection section to avoid the impact on the connection section when laying asphalt. When the front panel needs to be disassembled, it is only necessary to simply separate the channel steel section. After the operation channel steel assembly is covered, avoid the connection section channel steel to lay asphalt, and the asphalt height is consistent with the channel steel assembly; S5: Disassembly and recycling. After the project construction is completed, the process of disassembling the connection structure is turned to. The first step is to conduct a comprehensive safety review of the entire assembled structure, aiming to fully verify the integrity of the assembled structure and the unobstructed state of the surrounding environment, confirm that there are no safety hazards, and ensure that the dismantling operation is carried out under the premise of absolute safety; The dismantling operation first separated the channel steel assembly from the bridge deck connection section, and gradually dismantled all the bolt connections assembled on the UHPC prefabricated bridge deck connection section. The UHPC prefabricated bridge deck was smoothly lifted using the precise control function of the gantry crane, and through delicate operations, the bolt sleeves of the upper connection section were smoothly separated from the high-strength bolts of the lower connection section.

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