Adjustable high assembled uHPC bridge deck panel light composite beam and bridge deck panel height adjusting method

Abstract

The application discloses a high-adjustable assembled UHPC bridge deck plate light combined beam and a bridge deck plate height adjusting method, comprising a steel beam, an assembling groove, an adjusting gasket, a prefabricated UHPC bridge deck plate and a steel base. A plurality of prefabricated UHPC bridge deck plates are used to form an assembled bridge deck plate, a steel base is arranged at the bottom of the prefabricated UHPC bridge deck plate, and an assembling groove and an adjusting gasket are arranged at the top of the steel beam, and a support is formed between the steel beam and the prefabricated UHPC bridge deck plate by the steel base, the assembling groove and the adjusting gasket. During construction and after use, the bridge deck elevation can be adjusted at any time in a simple and fast manner by increasing, decreasing or replacing the adjusting gaskets, the bridge has a strong self-repairing performance, and the reliability, environmental protection, economy and flexibility of the bridge are remarkably improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of bridge engineering, in particular to an adjustable high assembled UHPC bridge deck slab light composite beam and a bridge deck slab height adjusting method. BACKGROUND

[0002] In recent years, as a new type of cement-based composite material with super-high mechanical properties and super-high durability, ultra-high performance concrete (UHPC) can effectively reduce the structural self-weight and improve the structural span, and has been applied in bridge engineering. For example, it is used for bridge deck pavement, key stress parts of bridge structure, and new types of bridge structure. Among them, the steel-UHPC bridge deck slab composite beam structure has light self-weight, high strength, strong spanning capacity, good crack resistance and low creep. Some research and application have been carried out for this type of structure at home and abroad. For example, Chinese patent CN217499903U discloses a honeycomb type narrow steel box-UHPC bridge deck slab composite beam bridge. In this patent, a steel box beam-UHPC bridge deck slab composite beam structure is introduced. The UHPC bridge deck slab is a cast-in-place structure, which requires formwork for construction and is limited by climate conditions for maintenance, and the construction period is slightly longer.

[0003] Assembled structure has the advantages of short construction period, little influence of construction by weather and other factors, low labor consumption, easy control of engineering quality, convenience for structure later reconstruction and reinforcement, and saving of formwork and other building resources. For the assembled UHPC bridge deck slab composite beam structure, there are few research results. For example, Chinese patent CN111206489A discloses an assembled wave-shaped web steel box-UHPC composite beam bridge and a construction method. In this patent, a structure type combined by wave-shaped web steel box and prefabricated UHPC bridge deck slab is introduced. However, the bridge deck slab is only partially prefabricated structure, the cantilever part is cast-in-place, and there are many cast-in-place wet joints between prefabricated bridge deck slabs. The quality of cast-in-place part of bridge deck and the connection part of cast-in-place and prefabricated part is not easy to control, and the construction period is still long. At the same time, when prefabricated components of assembled structure are mass-produced, size errors are inevitable, and height difference at joint is prone to occur in actual assembly work. In the previous research results, whether it is cast-in-place structure or assembled structure, the elevation of UHPC bridge deck slab cannot be flexibly adjusted according to the site conditions. When installation error occurs during construction or bridge head bumping problem occurs after use, simple measures cannot be taken to relieve the problem, and the application has certain limitations. SUMMARY

[0004] In view of the above defects of the prior art, an adjustable high assembled UHPC bridge deck slab light composite beam and a bridge deck slab height adjusting method are provided. During construction and after use, the bridge deck elevation can be adjusted at any time by increasing, decreasing or replacing the height adjusting gasket, which has strong self-repairing performance and significantly improves the reliability, environmental protection, economy and flexibility of the bridge.

[0005] The technical scheme adopted by the present application to solve the above technical problems is:

[0006] The adjustable high assembly type UHPC bridge deck plate light composite beam is characterized in that:

[0007] The steel beams are arranged along the transverse direction of the bridge, and steel beam transverse plates are arranged between the steel beams.

[0008] The assembly groove is fixedly arranged on the top of each steel beam and is arranged in sections along the longitudinal direction of the bridge.

[0009] The prefabricated UHPC bridge deck plate is assembled into the entire bridge deck plate along the longitudinal direction of the bridge. The steel base is fixedly arranged on the top of the prefabricated UHPC bridge deck plate, and the bottom of the steel base is fixedly arranged in the assembly groove in a detachable connection mode, and the steel base is placed above the height adjustment gasket.

[0010] According to the above technical scheme, the height adjustment gasket has multiple thickness specifications, and the corresponding thickness and number of height adjustment gaskets are selected according to the requirements.

[0011] According to the above technical scheme, the height adjustment gasket adopts the form of a steel-rubber gasket, and a single height adjustment gasket is bonded by a bonding agent from a steel plate and a rubber sheet. The thickness of the steel plate is not less than 2 mm, and the thickness of the rubber sheet is not less than 3 mm. Multiple height adjustment gaskets are stacked in the assembly groove with the rubber surface facing up.

[0012] According to the above technical scheme, the assembly groove is segmented and corresponds to the segmentation of the prefabricated UHPC bridge deck plate. The length of the assembly groove is not greater than the width of a single prefabricated UHPC bridge deck plate, and the inner width of the assembly groove is greater than the width of the steel base in the prefabricated UHPC bridge deck plate by 4-60 mm.

[0013] According to the above technical scheme, the assembly groove is a steel structure rectangular groove, and the height adjustment gasket adopts a rectangular gasket of a corresponding size. The assembly groove is fixedly arranged on the top of each steel beam and corresponds to the web of the steel beam.

[0014] According to the technical scheme, the shear bolts are symmetrically arranged on both sides of the web of the steel base, the shear bolts are arranged along the longitudinal direction of the bridge at intervals on both sides of the web of the steel base, and the interval is not greater than 1m; the heads of the shear bolts are welded on both sides of the web of the steel base, and the fixed height is set according to requirements; a plurality of pairs of U-shaped long holes from top to bottom are symmetrically arranged on both side walls of the long direction of the assembling groove corresponding to the shear bolts, and the width of the U-shaped long hole is within 10mm greater than the rod diameter of the shear bolt; the screw rod of the shear bolt is placed in the U-shaped long hole with the steel base, and the nut is tightened on the shear bolt, so that the nut is tightly attached to the outer wall of the assembling groove.

[0015] According to the technical scheme, the steel base adopts a steel structure, and the distance between the two ends is more than 10mm from the edge of the prefabricated UHPC bridge deck.

[0016] According to the technical scheme, in the longitudinal direction of the bridge, a gap of 2-10mm is provided between the two adjacent prefabricated UHPC bridge deck panels, and the thickness of the single prefabricated UHPC bridge deck panel is not greater than 200mm; the upper surface steel mesh and the lower surface steel mesh are arranged in the prefabricated UHPC bridge deck panel, the top of the steel base is welded and fixed with the upper surface steel mesh, and the middle of the steel base is welded and fixed with the lower surface steel mesh.

[0017] The panel height adjustment method of the assembled UHPC bridge deck light composite beam bridge is characterized in that: any one of the above-mentioned adjustable assembled UHPC bridge deck light composite beams is used, and the method comprises the following steps:

[0018] S1: according to the design requirements, prefabricate each component of the adjustable assembled UHPC bridge deck light composite beam in the factory, and transport all the components to the site, and then install the steel beam fixed with the assembling groove;

[0019] S2: place the height adjustment shims in each assembling groove to meet the design slope and design elevation of the bridge deck;

[0020] S3: hoist and install the prefabricated UHPC bridge deck with the steel base one by one, so that each steel base is placed in each assembling groove;

[0021] S4: verify whether the assembled overall bridge deck is flat; if the elevations of all the prefabricated UHPC bridge decks meet the design requirements, the steel base is fixed in the assembling groove in a detachable connection mode, and the installation of the prefabricated UHPC bridge deck is completed; if there is an error between the local and the design elevation after assembly, the prefabricated UHPC bridge deck at the place is lifted by using a jack or hoisting, the number or thickness of the height adjustment shims in the corresponding assembling groove of the prefabricated UHPC bridge deck is adjusted, so that the bridge deck at the place meets the design elevation; and then the steel base is fixed in the assembling groove in a detachable connection mode;

[0022] S5: complete the construction of the bridge deck asphalt, bridge guardrail and other structures.

[0023] According to the above technical solution, step S6 is also included: When the bridge has been in use for a period of time, if there is a difference in elevation between the bridge deck and the surrounding road surface and bridge deck, calculate the adjustment height of each precast UHPC bridge panel in the local area that needs to be adjusted to make the bridge deck smooth. Loosen the fixed connection between the steel base and the assembly slot, and lift the local precast UHPC bridge panel in turn by jacking or hoisting. Adjust the number or thickness of the height adjustment shims in the corresponding assembly slot according to the calculation results to make the bridge deck smooth. Then, fix the steel base in the assembly slot in a detachable connection to complete the bridge panel height adjustment.

[0024] The present invention has the following beneficial effects:

[0025] 1. A bridge deck is assembled using several prefabricated UHPC bridge decks. A steel base is installed at the bottom of the prefabricated UHPC bridge deck, and an assembly groove and height adjustment shims are installed at the top of the steel beam. The steel base, assembly groove, and height adjustment shims form a support between the steel beam and the prefabricated UHPC bridge deck. Based on the above measures, this embodiment has the following advantages:

[0026] First, this implementation method allows for quick and easy adjustment of the bridge deck elevation at any time by adding, removing, or replacing height adjustment shims. It is adjustable in both upward and downward directions and possesses strong self-correcting capabilities. During construction, the flexible on-site control of the bridge deck elevation easily resolves the common problem of dimensional errors in prefabricated components during mass production of prefabricated structures, further improving construction efficiency. Furthermore, after the bridge has been in use for a period of time, if uneven foundation settlement causes bridge approach slab settlement, this implementation method can adjust the bridge deck elevation by adding, removing, or replacing height adjustment shims, ensuring a smooth transition. Compared to other methods for handling bridge approach slab settlement, this real-time method is faster, has minimal impact on traffic, requires no additional building materials, and is a green and economical solution.

[0027] Secondly, all components are prefabricated in the factory, with no cast-in-place structures. After each component is hoisted into place, installation can be completed on-site simply by tightening the shear bolts. This minimizes the construction period, eliminates weather restrictions, saves manpower and formwork resources, and generates no construction waste. At the same time, the quality of all components can be well controlled.

[0028] Finally, this real-time method combines steel beams with precast UHPC bridge decks to form a composite beam structure. Both utilize high-strength materials, have large spans, and are lightweight, facilitating transportation and assembly, thus saving on substructure costs. Furthermore, the UHPC bridge decks offer excellent durability, high strength, crack resistance, and low creep, preventing long-term problems such as fatigue, cracking, corrosion, and creep. Overall, the structure is significantly more economical than other bridge superstructure types under similar conditions, such as concrete beams, steel-concrete composite beams, and steel box girders.

[0029] 2. Significantly enhanced shear resistance between the steel beam and the precast UHPC bridge deck: This embodiment uses a steel base embedded in the UHPC bridge deck and reliably welded to the bridge deck reinforcement as a shear-resistant component. Shear resistance is achieved by inserting it into the assembly slot and fixing it with shear bolts. Compared with the shear resistance methods of previous technologies that used shear studs, PBL connectors, etc., the shear resistance performance is greatly improved, and the shear-resistant component has high rigidity and is not easily damaged. Attached Figure Description

[0030] Figure 1 This is a cross-sectional schematic diagram of an embodiment provided by the present invention;

[0031] Figure 2 yes Figure 1 AA section view;

[0032] Figure 3 yes Figure 1 BB section view;

[0033] Figure 4 This is a schematic diagram of the installation of a single assembly slot according to an embodiment of the present invention;

[0034] Figure 5 This is a plan view of a single assembly slot installation according to an embodiment of the present invention;

[0035] Figure 6 yes Figure 5 CC section view;

[0036] In the diagram, 1. Steel beam; 2. Steel beam diaphragm; 3. Assembly slot; 3-1. U-shaped elongated hole; 4. Height adjustment shim; 5. Precast UHPC bridge deck; 5-1. Upper surface steel mesh; 5-2. Lower surface steel mesh; 6. Steel base; 7. Shear bolt; 8. Nut; 9. Bridge deck asphalt; 10. Bridge railing. Detailed Implementation

[0037] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0038] Reference Figures 1-6 As shown, the adjustable height prefabricated UHPC bridge deck lightweight composite beam provided by the present invention includes a steel beam 1, a plurality of steel beams are arranged at intervals along the transverse direction of the bridge, and a steel beam diaphragm 2 is provided between the steel beams.

[0039] The assembly slot 3 is fixed on the top of each steel beam and is arranged in sections along the longitudinal direction of the bridge. Several height adjustment shims 4 are provided in the assembly slot. The plane dimensions of the height adjustment shims match the slot opening dimensions of the assembly slot (the length and width of the shims are slightly smaller than the length and width of the slot opening).

[0040] The prefabricated UHPC bridge deck 5 is assembled from several prefabricated UHPC bridge decks along the longitudinal direction of the bridge to form the entire bridge deck (i.e., a single prefabricated UHPC bridge deck spans across both sides of the bridge). Several steel bases 6 are spaced apart at the bottom of each prefabricated UHPC bridge deck. The placement of the steel bases matches the placement of the assembly slots, and the bottom width of the steel bases matches the slot opening size. The top of the steel bases is fixed inside the prefabricated UHPC bridge deck (the upper end of the steel base is pre-embedded inside the prefabricated UHPC bridge deck), and the bottom of the steel bases is fixed in the assembly slots in a detachable connection manner. The steel bases are placed directly above the height adjustment shims.

[0041] This embodiment uses several prefabricated UHPC bridge panels to form an assembled bridge panel. A steel base is installed at the bottom of the prefabricated UHPC bridge panel, and an assembly groove and height adjustment shims are installed at the top of the steel beam. The steel base, assembly groove, and height adjustment shims form a support between the steel beam and the prefabricated UHPC bridge panel. Based on the above measures, this embodiment has the following advantages:

[0042] First, this implementation method allows for quick and easy adjustment of the bridge deck elevation at any time by adding, removing, or replacing height adjustment shims. It is adjustable in both upward and downward directions and possesses strong self-correcting capabilities. During construction, the flexible on-site control of the bridge deck elevation easily resolves the common problem of dimensional errors in prefabricated components during mass production of prefabricated structures, further improving construction efficiency. Furthermore, after the bridge has been in use for a period of time, if uneven foundation settlement causes bridge approach slab settlement, this implementation method can adjust the bridge deck elevation by adding, removing, or replacing height adjustment shims, ensuring a smooth transition. Compared to other methods for handling bridge approach slab settlement, this real-time method is faster, has minimal impact on traffic, requires no additional building materials, and is a green and economical solution.

[0043] Secondly, all components are prefabricated in the factory, with no cast-in-place structures. After each component is hoisted into place, installation can be completed on-site simply by tightening the shear bolts. This minimizes the construction period, eliminates weather restrictions, saves manpower and formwork resources, and generates no construction waste. At the same time, the quality of all components can be well controlled.

[0044] Finally, this real-time method combines steel beams with precast UHPC bridge decks to form a composite beam structure. Both utilize high-strength materials, have large spans, and are lightweight, facilitating transportation and assembly, thus saving on substructure costs. Furthermore, the UHPC bridge decks offer excellent durability, high strength, crack resistance, and low creep, preventing long-term problems such as fatigue, cracking, corrosion, and creep. Overall, the structure is significantly more economical than other bridge superstructure types under similar conditions, such as concrete beams, steel-concrete composite beams, and steel box girders.

[0045] In some embodiments, the height adjustment shims are available in various thicknesses, and the appropriate thickness and quantity of height adjustment shims are selected according to requirements. By designing several thickness sizes of height adjustment shims, and depending on the different specifications and quantities of the height adjustment shims selected, all possible total height requirements of the shims can be achieved.

[0046] Preferably, the height adjustment shim is in the form of a steel-rubber shim, and a single height adjustment shim is made of a steel plate and a rubber sheet bonded together with an adhesive; the thickness of the steel plate is not less than 2mm, and the thickness of the rubber sheet is not less than 3mm.

[0047] Preferably, multiple height adjustment shims are stacked and placed in the assembly slot with the rubber side facing up.

[0048] In some of the above embodiments, the assembly groove segments correspond to the prefabricated UHPC bridge panel segments, the length of the assembly groove is not greater than the width of a single prefabricated UHPC bridge panel, and the inner width of the assembly groove is 4 to 60 mm larger than the width of the steel base in the prefabricated UHPC bridge panel.

[0049] Preferably, the assembly slot is a rectangular steel structure slot, and the height adjustment shims are rectangular shims of the corresponding size; the assembly slot is fixed on the top of each steel beam and corresponds to the web of the steel beam.

[0050] In some of the above embodiments, shear bolts 7 are symmetrically arranged on both sides of the web of the steel base. The shear bolts are spaced apart along the longitudinal direction of the bridge on both sides of the web of the steel base, with a spacing of no more than 1m. The heads of the shear bolts are welded to both sides of the web of the steel base, and the fixing height is set according to requirements. On the two side walls along the length of the assembly slot, corresponding to the shear bolts, several pairs of U-shaped elongated holes are symmetrically arranged from top to bottom. The width of the U-shaped elongated holes is within 10mm larger than the diameter of the shear bolt. The bolts of the shear bolts are placed in the U-shaped elongated holes along with the steel base, and nuts 8 are tightened on the shear bolts so that the nuts are tightly attached to the outer wall of the assembly slot. The positioning and spacing of the shear bolts along the longitudinal direction of the bridge are consistent with the positioning and spacing of the U-shaped elongated holes in the assembly slot. The steel base is installed in the assembly slot through the shear bolts and the U-shaped elongated holes.

[0051] This embodiment significantly enhances the shear resistance between the steel beam and the precast UHPC bridge deck. The steel base embedded in the UHPC bridge deck and reliably welded to the bridge deck reinforcement serves as the shear-resistant component. Shear resistance is achieved by inserting it into the assembly slot and fixing it with shear bolts. Compared with the shear resistance methods of previous technologies that used shear studs, PBL connectors, etc., this method greatly improves the shear resistance performance and the shear-resistant component has high rigidity and is not easily damaged.

[0052] Preferably, the shear bolt performance grade is not lower than 4.8 and the size is not less than M24.

[0053] In some of the above embodiments, both the steel base and the steel beam adopt a steel profile structure. The width of the bottom horizontal section of the steel base is smaller than the width of the assembly groove. The two ends of the steel base are at least 10mm away from the edge of the prefabricated UHPC bridge deck panel.

[0054] In some of the above embodiments, a gap of 2-10mm is provided between two adjacent precast UHPC bridge decks in the longitudinal direction of the bridge, and the thickness of a single precast UHPC bridge deck is no more than 200mm; an upper surface steel mesh 5-1 and a lower surface steel mesh 5-2 are provided inside the precast UHPC bridge deck, the top of the steel base is welded and fixed to the upper surface steel mesh, and the middle part of the steel base is welded and fixed to the lower surface steel mesh.

[0055] This invention also provides a method for adjusting the height of a lightweight composite beam bridge using prefabricated UHPC bridge deck, employing any of the adjustable prefabricated UHPC bridge deck lightweight composite beams described above, comprising the following steps:

[0056] S1: According to the design requirements, prefabricate the various components of the adjustable height prefabricated UHPC bridge deck lightweight composite beam in the factory. Specifically, weld the assembly slots to the upper surface of the steel beam, and fix the shear bolts to the steel base of the prefabricated UHPC bridge deck; calculate the number of height adjustment shims required in each assembly slot and the thickness of each shim according to the bridge deck elevation, and manufacture the height adjustment shims; transport all components to the site, and then install the steel beam with the assembly slots fixed thereon.

[0057] S2: Place calculated height adjustment shims in each assembly slot to meet the bridge deck design slope and design elevation;

[0058] S3: The prefabricated UHPC bridge deck with steel base is hoisted and installed one by one, so that each steel base is placed in each assembly slot, and the shear bolts welded to the web of the steel base are inserted into the corresponding U-shaped long hole of the assembly slot.

[0059] S4: Verify whether the overall bridge deck is flat after assembly and whether there are any manufacturing or installation errors; if the elevation of each prefabricated UHPC bridge panel meets the design requirements, fix the steel base in the assembly slot in a detachable connection manner (i.e., in this embodiment, tighten the shear bolts of each panel outside the assembly slot) to complete the installation of the prefabricated UHPC bridge panel; if there is a local error between the assembled and the design elevation, use jacks to lift or hoist the prefabricated UHPC bridge panel at that location, and adjust the number or thickness of the height adjustment shims in the corresponding assembly slot to make the bridge deck at that location meet the design elevation; then fix the steel base in the assembly slot in a detachable connection manner.

[0060] S5: Complete the construction of structures such as bridge deck asphalt 9 and bridge railing 10.

[0061] Furthermore, step S6 is also included: When the bridge has been in use for a period of time, if uneven settlement causes a difference in elevation between the bridge deck and the surrounding road surface and bridge deck, resulting in problems such as bridge approach slab slabs, the adjustment height of each precast UHPC bridge panel needs to be adjusted to make the bridge deck smooth. The fixed connection between the steel base and the assembly slot is loosened (i.e., in this embodiment, the shear bolts of each steel base are loosened). The local precast UHPC bridge panel is lifted sequentially by jacking or hoisting. The number or thickness of the height adjustment shims in the corresponding assembly slot is adjusted according to the calculation results to make the bridge deck smooth. Then, the steel base is fixed in the assembly slot in a detachable connection manner (i.e., in this embodiment, the shear bolts of each panel are tightened again outside the assembly slot) to complete the bridge panel height adjustment.

[0062] In view of the above-described embodiments, a preferred embodiment is provided as follows:

[0063] The bridge is 20m wide with a span of 1×42m. The superstructure uses adjustable-height prefabricated UHPC lightweight composite beams, including 6 steel beams. The design vehicle load rating is City-B, and the design safety level is Level 1. The abutments are gravity abutments, and the foundation is a pile foundation. The prefabricated bridge deck uses ultra-high performance concrete (UHPC120), HRB600 grade steel reinforcement, and Q355C steel. The installation method of the adjustable-height prefabricated UHPC lightweight composite beams mainly includes the following steps:

[0064] Step 1: The factory completes the fabrication of steel beams and corresponding steel beam diaphragms, prefabricated UHPC bridge decks with steel bases, assembly slots, height adjustment shims, and shear bolts. Simultaneously, the assembly slots are welded to the upper surface of the steel beams, and the shear bolts are welded to the steel bases of the prefabricated UHPC bridge decks. Based on the bridge deck elevation, the number of height adjustment shims required in each assembly slot and the thickness of each shim are calculated, and the height adjustment shims are fabricated. Details are as follows:

[0065] The steel beams are made of H-beams, with a beam height of 2m, a flange width of 650mm, a thickness of 40mm, and a web thickness of 20mm. The steel beams are spaced 3.5m apart in the transverse direction along the bridge. The corresponding steel beam diaphragms are 12mm thick and spaced 4m apart in the longitudinal direction along the bridge.

[0066] The bridge deck of the precast UHPC bridge with steel bases uses UHPC120 ultra-high performance concrete precast slabs. The entire bridge deck is assembled from multiple precast UHPC bridge deck slabs with steel bases along the longitudinal direction of the bridge. Each slab is 160mm thick, 20m long (the same as the bridge width), and 2.49m wide. The upper surface of the slab is reinforced with HRB600 steel bars of 12mm diameter and 50mm spacing along the length and 12mm diameter and 100mm spacing along the width, forming an upper surface steel mesh. The lower surface of the slab is reinforced with HRB600 steel bars of 25mm diameter and 150mm spacing along the length and 12mm diameter and 100mm spacing along the width, forming a lower surface steel mesh. There is a 10mm gap between adjacent slabs.

[0067] The steel base portion of the precast UHPC bridge deck with steel base is made of I40a I-beams. The upper end is embedded in the precast UHPC bridge deck and welded to the steel mesh on the upper and lower surfaces of the deck. The lower end is placed on the height adjustment shims in the assembly slot. Each precast UHPC bridge deck has a steel base corresponding to the web of each steel beam. Each steel base is 142mm wide and 2460mm long, with both ends 15mm away from the edge of the precast UHPC bridge deck.

[0068] The assembly trough is a rectangular steel structure with a wall thickness and bottom plate thickness of 10mm. It is welded to the upper surface of the steel beam corresponding to the web of the steel beam and is divided into multiple sections along the longitudinal direction of the steel beam. The sections and their positioning correspond one-to-one with the steel bases in the prefabricated UHPC bridge deck. Each section of the assembly trough is 2490mm long, equal to the width of the prefabricated UHPC bridge deck, and has an inner width of 162mm. Several pairs of long holes from top to bottom are symmetrically arranged on the two side walls along the longitudinal direction of the assembly trough at a certain interval, with a spacing of 0.5m and a hole width of 36mm.

[0069] The height adjustment shims are steel-rubber shims; the shims are 2465mm long and 152mm wide; each height adjustment shim is made of steel plate and rubber sheet bonded together with adhesive. According to the bridge deck design elevation, the steel plate is 3mm thick and the rubber sheet is 5mm thick. Five height adjustment shims are stacked and placed in each assembly slot.

[0070] The shear bolts are ordinary C-grade M30 bolts with a performance grade of 4.8. The bolt heads are welded to the left and right sides of the steel base web of the precast UHPC bridge deck and are symmetrically arranged along both sides. The shear bolts are positioned longitudinally along the bridge and the spacing is consistent with the positioning and spacing of the long holes in the assembly slot.

[0071] Transport all prefabricated components to the site and install the steel beams;

[0072] Step 2: Place height adjustment shims in each assembly slot, with the rubber side facing up.

[0073] Step 3: Hoist and install the prefabricated UHPC bridge deck with steel base one by one, place each steel base in the assembly slot, and at the same time, insert the shear bolts welded to the web of the steel base into the corresponding long holes of the assembly slot.

[0074] Step 4: Verify whether the overall bridge deck is flat after assembly and whether there are any manufacturing or installation errors;

[0075] Upon verification, it was found that the elevation of some precast UHPC bridge panels had an error of 2-3mm. The precast UHPC bridge panels in this area were lifted by hoisting or jacking. One height adjustment shim was removed from the assembly slot at this location, and its thickness was adjusted or the height adjustment shim was replaced to make the panel meet the bridge deck elevation requirements. The precast UHPC bridge panels with steel bases were then repositioned. After the elevation of all precast UHPC bridge panels met the requirements, the shear bolts of each panel were tightened outside the assembly slot to complete the installation of the precast UHPC bridge panels.

[0076] Step 5: Complete the construction of the bridge deck asphalt, bridge railings and other structures.

[0077] After a period of use, uneven settlement of the foundation caused a height difference between the bridge deck and the road surface behind the abutment, with the bridge deck elevation being higher than the road surface elevation behind the abutment. This resulted in problems such as vehicle slab settlement at the bridge approach. The method for adjusting the bridge deck height using the adjustable-height prefabricated UHPC lightweight composite beam of this invention is as follows:

[0078] Calculations show that to ensure a smooth transition from the bridge deck to the road surface, the elevation of the precast UHPC bridge panel at the junction with the road surface needs to be lowered by 7-10mm. Loosen the shear bolts of each panel, and use jacks or hoisting to lift the corresponding precast UHPC bridge panels one by one. Remove 1-3 height adjustment shims from the assembly slot at that location, adjust their thickness or replace the shims to ensure the panel meets the elevation requirements. Replace the precast UHPC bridge panel with the steel base, verify that the bridge deck is smooth from the road surface at that location, and then tighten the shear bolts of each panel outside the assembly slot to complete the bridge panel height adjustment.

[0079] The above are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, any equivalent changes made in accordance with the claims of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A height-adjustable prefabricated UHPC bridge deck lightweight composite beam, characterized in that: include Steel beams, several steel beams are arranged at intervals along the transverse direction of the bridge, and steel beam diaphragms are provided between the steel beams; The assembly slots are fixed on the top of each steel beam and are arranged in sections along the longitudinal direction of the bridge. Several height adjustment shims are provided in the assembly slots, and the planar dimensions of the height adjustment shims match the slot opening dimensions of the assembly slots. The prefabricated UHPC bridge deck is assembled from several prefabricated UHPC bridge decks along the longitudinal direction of the bridge to form the entire bridge deck. Several steel bases are spaced apart at the bottom of each prefabricated UHPC bridge deck. The placement of the steel bases matches the placement of the assembly slots, and the bottom width of the steel bases matches the opening size of the assembly slots. The top of the steel bases is fixed inside the prefabricated UHPC bridge deck, and the bottom of the steel bases is fixed inside the assembly slots in a detachable connection manner. The steel bases are placed directly above the height adjustment shims. The height adjustment shims are available in various thicknesses; select the appropriate thickness and quantity of height adjustment shims according to your needs. The height adjustment shims are made of steel-rubber shims. A single height adjustment shim is made of a steel plate and a rubber sheet bonded together with an adhesive. The steel plate is not less than 2mm thick and the rubber sheet is not less than 3mm thick. Multiple height adjustment shims are stacked in the assembly slot with the rubber side facing up. The assembly slots are segmented to correspond to the precast UHPC bridge deck segments. The length of the assembly slot is no greater than the width of a single precast UHPC bridge deck. The inner width of the assembly slot is 4 to 60 mm larger than the width of the steel base in the precast UHPC bridge deck. The assembly slot is a rectangular steel structure slot, and the height adjustment shims are rectangular shims of the corresponding size; the assembly slot is fixed on the top of each steel beam and corresponds to the web of the steel beam; Shear bolts are symmetrically arranged on both sides of the web of the steel base. The shear bolts are spaced apart along the longitudinal direction of the bridge on both sides of the web of the steel base, with a spacing of no more than 1m. The heads of the shear bolts are welded to both sides of the web of the steel base, and the fixing height is set according to the requirements. On the two side walls of the assembly slot along the length direction, corresponding to the shear bolts, several pairs of U-shaped long holes are symmetrically arranged from top to bottom. The width of the U-shaped long holes is no more than 10mm larger than the diameter of the shear bolt. The bolts of the shear bolts are placed in the U-shaped long holes along with the steel base, and the nuts are tightened on the shear bolts so that the nuts are tightly attached to the outer wall of the assembly slot. In the longitudinal direction of the bridge, there is a gap of 2 to 10 mm between two adjacent precast UHPC bridge panels, and the thickness of a single precast UHPC bridge panel is no more than 200 mm; there are upper and lower surface steel meshes inside the precast UHPC bridge panel, the top of the steel base is welded and fixed to the upper surface steel mesh, and the middle of the steel base is welded and fixed to the lower surface steel mesh.

2. The adjustable-height prefabricated UHPC bridge deck lightweight composite beam according to claim 1, characterized in that: The steel base adopts a steel profile structure, with both ends at least 10mm away from the edge of the precast UHPC bridge panel.

3. A method for adjusting the panel height of a lightweight composite beam bridge using prefabricated UHPC bridge deck, characterized in that: The lightweight composite beam with adjustable height prefabricated UHPC bridge deck as described in any one of claims 1-2 includes the following steps: S1: According to the design requirements, prefabricate the various components of the adjustable height prefabricated UHPC bridge deck lightweight composite beam in the factory, transport all components to the site, and then install the steel beams with fixed assembly slots. S2: Place height adjustment shims in each assembly slot to meet the design slope and design elevation of the bridge deck; S3: The prefabricated UHPC bridge panels with steel bases are hoisted and installed one by one, so that each steel base is placed in its respective assembly slot; S4: Verify whether the overall bridge deck is flat after assembly; if the elevation of each precast UHPC bridge panel meets the design requirements, fix the steel base in the assembly slot in a detachable manner to complete the installation of the precast UHPC bridge panel; if there is a local error between the assembled and the design elevation, use jacks or hoisting to lift the precast UHPC bridge panel at that point, and adjust the number or thickness of the height adjustment shims in the corresponding assembly slot to make the bridge deck at that point meet the design elevation; then fix the steel base in the assembly slot in a detachable manner. S5: Complete the construction of bridge deck asphalt, bridge railings and other structural components.

4. The method for adjusting the panel height of a lightweight composite beam bridge using prefabricated UHPC bridge deck as described in claim 3, characterized in that: The process also includes step S6: If, after a period of use, there is a difference in elevation between the bridge deck and the surrounding road surface and bridge deck, calculate the height adjustment of each precast UHPC bridge panel in the local area that needs to be adjusted to make the bridge deck smooth. Loosen the fixed connection between the steel base and the assembly slot, and lift the local precast UHPC bridge panel in sequence by using jacks or hoisting. Adjust the number or thickness of the height adjustment shims in the corresponding assembly slot according to the calculation results to make the bridge deck smooth. Then, fix the steel base in the assembly slot in a detachable connection to complete the bridge panel height adjustment.

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