Precast Unreinforced UHPC Bridge Deck and Rapid Assembly Method

Abstract

This invention discloses a prefabricated bridge deck with unreinforced UHPC and a rapid assembly method. The bridge deck uses UHPC as the main material, with a constraint shell serving as the UHPC forming template. The constraint shell is connected to the UHPC via connecting studs and small-diameter steel sleeves. The constraint shell is formed by sheet metal cutting, bending, and welding, and a partition or welded steel sleeve is placed inside the shell. The steel sleeve with the installation perforation is vertically fixed to the bottom surface or partition extending from the enclosure plate. Ultra-high performance concrete is poured to form the prefabricated bridge deck with the constraint shell. This prefabricated bridge deck is prefabricated in the factory, fully utilizing the material properties of UHPC, optimizing the UHPC panel structure, eliminating the need for on-site steam curing, and solving problems such as difficult quality control, easy cracking, and unstable performance of traditional UHPC bridge decks due to reinforcement affecting fiber distribution during on-site construction.

Description

Technical Field

[0001] This invention relates to a prefabricated, unreinforced UHPC bridge deck and its rapid assembly, belonging to the field of bridge engineering. Background Technology

[0002] Traditionally, epoxy asphalt paving is used for steel bridge decks, which involves directly laying asphalt on the steel bridge deck. This type of paving structure has a high level of local stress under the action of vehicle wheels, and the orthotropic steel bridge deck of the steel box girder is prone to local cracking, resulting in a short service life.

[0003] UHPC (Ultra-High-Pressure Polymer) material possesses extremely high compressive strength and excellent durability. To fully utilize the mechanical properties of UHPC, some have proposed adding a UHPC pavement layer on top of the steel bridge deck. The common practice is to first weld stud connections onto the top surface of the steel box girder, then tie reinforcing bars and pour the UHPC, finally subjecting it to on-site steam curing. While this method can significantly reduce localized stress levels compared to traditional epoxy asphalt pavement, on-site UHPC pouring results in a long construction period, lower construction efficiency, and high on-site steam curing costs. Furthermore, the arrangement of reinforcing bars and studs within the UHPC pavement slab can interfere with the diffusion path of the steel fibers, leading to poor fiber dispersion and uneven distribution, which in turn affects the mechanical properties of the UHPC bridge deck pavement layer. In addition, this on-site pouring, densely reinforced UHPC pavement is also relatively expensive.

[0004] Therefore, it is necessary to develop new prefabricated unreinforced UHPC bridge decks with constrained shells and their rapid assembly technology. Summary of the Invention

[0005] Objective: This invention provides a prefabricated bridge deck with unreinforced UHPC (Ultra-High-Pressure Polymer) panels. The bridge deck uses UHPC as the main material, with a constraint shell serving as the UHPC forming template. The constraint shell is connected to the UHPC via connecting studs and small-diameter steel sleeves. The constraint shell is standardized and modular, eliminating the need for traditional steel reinforcement. This prefabricated bridge deck is prefabricated in the factory, fully utilizing the material properties of UHPC, optimizing the UHPC panel structure, and eliminating the need for on-site steam curing. It solves problems such as difficulty in controlling on-site construction quality, easy cracking, and unstable performance of UHPC panels due to reinforcement affecting fiber distribution, common in traditional UHPC bridge decks. This invention also provides a rapid assembly technology with high assembly accuracy, solving the problems of complex construction processes and low construction efficiency associated with traditional on-site casting methods.

[0006] The technical solution adopted by this invention to solve its technical problem is as follows:

[0007] The prefabricated, unreinforced UHPC bridge deck is a steel-concrete structure, characterized by...

[0008] The constraint shell is formed by cutting, bending and welding sheet metal, and a partition or welded steel sleeve is placed inside the shell. The constraint shell has at least a circumferentially enclosed frame structure. The enclosing plate is formed by welding high-strength steel plate. The forming stage provides constraint for the forming of ultra-high performance concrete. The installation stage provides constraint when the internal ultra-high performance concrete is subjected to compression and tension. At least a mounting hole is provided inside the constraint shell. The steel sleeve where the mounting hole is located is fixed vertically to the bottom surface or partition extending from the enclosing plate.

[0009] Ultra-high performance concrete is poured together with the constraint shell to form a precast bridge deck, and the upper and lower surfaces of the integrally formed bridge deck have flat planes.

[0010] The steel fibers are arranged regularly in the direction of the bridge, and the two ends of the steel fibers are welded to the side of the constraint shell.

[0011] The longitudinally and laterally arranged partitions divide the interior of the confined shell into multiple independent casting spaces, and place cross-shaped support frames within these independent casting spaces.

[0012] The bottom surface is located on the lower surface of the constraint shell, and the mounting hole penetrates the bottom plate.

[0013] It also includes studs installed on the base plate or partition.

[0014] The mounting hole is a stepped hole, providing space to accommodate the nut.

[0015] The confined shell forms a closed cavity enclosed by the top and bottom plates, which is filled with ultra-high performance concrete by grouting.

[0016] A rapid assembly method for prefabricated unreinforced UHPC bridge decks, characterized by extensive use of the prefabricated unreinforced UHPC bridge decks described in any one of claims 1 to 7, and the following steps:

[0017] S1. Draw lines on the steel bridge installation surface according to the size of the precast bridge deck. The lines include lines along the bridge direction and lines in the transverse direction. After drawing the lines, a square installation area is formed. Within this installation area, the installation points of the connecting studs are determined and drawn using a special template. The connecting studs are then welded to the corresponding installation points.

[0018] S2, Install the T-shaped connecting steel plate along the marked line.

[0019] S3. Apply adhesive mortar or other adhesives or bonding materials to the installation area. Place the precast bridge deck from top to bottom in the installation area so that the connecting studs correspond one-to-one with the steel sleeves. Tighten with fastening nuts and then install the next precast bridge deck. After all the precast bridge decks are installed, weld at the joints and cut off the exposed parts of the embedded steel lifting rings on the bridge deck.

[0020] S4, and finally asphalt paving is carried out on the bridge surface to form an asphalt road.

[0021] A rapid assembly method for prefabricated unreinforced UHPC bridge decks, characterized by extensive use of the prefabricated unreinforced UHPC bridge decks described in any one of claims 1 to 7, and the following steps:

[0022] S1. Draw lines on the steel bridge installation surface according to the dimensions of the unreinforced UHPC bridge deck. The lines include lines in the longitudinal and transverse directions of the bridge. After drawing the lines, a square installation area is formed. Within this installation area, the installation points of the connecting studs are determined and drawn. The connecting studs are then welded to the corresponding installation points.

[0023] S2 Then install the T-shaped connecting steel plate along the marked line.

[0024] S3 applies adhesive mortar or other bonding agents / materials to the installation area, then reverses and snaps the precast bridge deck panels together along the connecting studs. Each connecting stud corresponds to a steel sleeve, and the studs are tightened with nuts. The next precast bridge deck panel is then installed. After all precast bridge deck panels are installed, welding is performed at the joints.

[0025] S4, asphalt paving is being carried out on the bridge surface.

[0026] Beneficial effects:

[0027] (1) This invention uses steel-UHPC structure as bridge deck of steel bridge, giving full play to the high durability of UHPC and solving the problems of insufficient durability of traditional concrete beam structure and high cost of pure UHPC beam structure.

[0028] (2) The present invention adopts the method of prefabricating components in the factory, which ensures good product consistency and quality, fully utilizes the material characteristics of UHPC, optimizes the UHPC panel structure, eliminates the on-site steam curing process, and solves the problems of difficult quality control and easy cracking of traditional UHPC bridge panels during on-site construction.

[0029] (3) Modular design: This invention does not require the configuration of traditional steel bars. It is prefabricated in the factory, which makes full use of the material characteristics of UHPC and eliminates the traditional steel bar reinforcement method. It solves the problem that the configuration of steel bars affects the fiber distribution and causes the UHPC panel performance to be unstable. At the same time, it improves construction efficiency and construction accuracy.

[0030] (4) The present invention uses the unreinforced UHPC bridge deck with a constrained shell as the compression zone of the beam structure, which fully utilizes the high strength of UHPC and solves the problem of easy cracking of the bottom plate of traditional prestressed concrete beams.

[0031] (5) The present invention improves the stability, fit and construction speed of the overall bridge deck structure by welding threaded connecting studs on the bridge deck and connecting the various structures as a whole by threaded connecting stud bolts.

[0032] (6) The present invention solves the problem of cracks that may occur between side materials after long-term use of UHPC by welding T-shaped plates to fix and splice the unreinforced ultra-high performance concrete precast slabs with constrained shells, thus improving the construction quality.

[0033] (7) The present invention adopts prefabricated construction, which has high assembly accuracy and solves the problems of complex construction process and low construction efficiency of traditional on-site pouring method. Attached Figure Description

[0034] Figure 1 This is a perspective view of the bridge deck in Embodiment 1.

[0035] Figure 2 for Figure 1 Another perspective diagram.

[0036] Figure 3 for Figure 2 Draw an abbreviated diagram of concrete.

[0037] Figure 4 This is style one of the constraint shells in Example 2.

[0038] Figure 5 This is style two of the constraint shell in Example 2.

[0039] Figure 6 This is a 3D view of the T-shaped connecting steel plates.

[0040] Figure 7 This is style one of the constraint shells in Example 3.

[0041] Figure 8 This is style two of the constraint shell in Example 3.

[0042] Figure 9 This is a schematic diagram of the first step in the assembly and construction process.

[0043] Figure 10 This is a schematic diagram of the second step in the assembly process.

[0044] Figure 11 This is a schematic diagram of step three in the assembly process.

[0045] Figure 12 This is a schematic diagram of step four in the assembly process.

[0046] Figure 13 This is a schematic diagram of exposed nodes in a typical design.

[0047] Figure 14 This is a schematic diagram after asphalt paving.

[0048] Figure 15 The installation node is hidden in the installation structure view.

[0049] In the picture:

[0050] Constraint housing 10, bottom surface 11, steel sleeve 111, bolt 112, side surface 12, concave-convex structure 13, steel lifting ring 14.

[0051] Ultra-high performance concrete 00

[0052] Bridge deck 20, marking line 21, bridge deck mounting unit 22, connecting stud 221, anchor head 2211, cross expansion joint 2212, T-shaped connecting steel plate 30, bolt hole 31.

[0053] Asphalt pavement 40. Detailed Implementation

[0054] Example 1

[0055] This invention discloses a prefabricated unreinforced UHPC bridge deck and its rapid assembly technology.

[0056] The bridge deck is an unreinforced UHPC bridge deck, which is a precast integral slab composed of a steel confinement shell 10 and ultra-high performance concrete 00. The confinement shell has at least two sides and may also have a bottom surface, where the sides confine the internal ultra-high performance concrete. In this embodiment, the confinement shell 10 is a channel-shaped structure with an open top, consisting of a bottom surface 11 and four side surfaces 12. This embodiment only illustrates a square channel-shaped structure. With appropriate deformation, it can also be a rectangular channel-shaped structure.

[0057] In this invention, constraint refers to the constraint that the shell exerts on the internal ultra-high performance concrete, especially when the bridge deck is subjected to compressive or tensile stress. This constraint has a positive effect on improving the mechanical properties of the bridge deck.

[0058] On the bottom surface of the constraint shell 10, specifically, a steel sleeve 111 and a stud 112 are welded, meaning the bottom surface 11 provides a mounting carrier for the steel sleeve and stud. The steel sleeve 111 is a sleeve vertically welded to the bottom plate of the constraint shell. This steel sleeve has a vertically penetrating through-hole that passes through the constraint shell in both the vertical and horizontal directions, providing a through-channel for plug-in connections. The stud 112 is vertically welded to the bottom plate of the constraint shell and is a solid structure used to enhance the bonding strength between the ultra-high performance concrete (UHPC) and the shell, preventing peeling. In this embodiment, the studs and steel sleeves are arranged intersectingly and dispersedly.

[0059] In this embodiment, the bottom surface 11 serves as the mounting surface. The bottom surface has a distinct stamped concave-convex structure 13. The presence of this concave-convex structure 13 provides clearance space for the T-shaped connecting steel plate 30 during the installation and construction phase, and the bottom surface 11 can ensure a sufficiently large mating contact surface with the steel bridge deck.

[0060] During installation, adhesive mortar or adhesive is used to assist in bonding between the bottom surface and the steel bridge deck, which also has the effects of corrosion prevention and seepage prevention.

[0061] Ultra-high performance concrete is poured into a confined shell 10 with welded studs and steel sleeves, and steel lifting rings 14 are pre-embedded in the ultra-high performance concrete. After steam curing, the ultra-high performance concrete solidifies in the confined shell to form a steel-reinforced UHPC bridge deck.

[0062] In this embodiment, the strength of the ultra-high performance concrete is 120-150 MPa, and the steel fiber content is 2%-4%.

[0063] Furthermore, the constrained shell and the precast ultra-high performance concrete bridge deck are assembled and constructed using a modular rapid assembly method. The steel sleeve and ultra-high performance concrete structure are reinforced with bolts, and the arrangement meets the requirements of local area bearing capacity and overall area crack resistance design.

[0064] The dimensions of the aforementioned unreinforced UHPC bridge deck are set according to design requirements, such as a 5m x 5m large panel.

[0065] The steel bridge deck can be in the form of a steel box girder, steel T-beam, etc. This embodiment uses a steel box girder bridge as an example, for reference... Figures 9 to 12Lines are marked on the steel bridge. Specifically, lines 21 are drawn on the mounting surface of the steel bridge deck according to the dimensions of the unreinforced UHPC bridge deck, forming several grid-shaped installation areas. Each installation area corresponds to an unreinforced UHPC bridge deck installation unit 22. Threaded connecting studs 221 are welded to each installation unit. These studs are vertically positioned at the welding location. "Threaded" means that the upper half of the connecting stud 221 is threaded. The connecting stud corresponds to a steel sleeve on the bridge deck. During installation, the connecting stud passes through the steel sleeve from bottom to top and is tightened with a fastening nut, forming a single unit. In other words, the unreinforced UHPC bridge deck is mechanically fixed to the steel bridge by bolts.

[0066] Furthermore, Figure 13 and Figure 14 The diagram illustrates another surface-mounted structure in which the locking nut is visible after installation. In this embodiment, the upper end of the connecting stud 221 engages with the locking nut.

[0067] Figure 15 A concealed installation structure is presented, in which the length of the steel sleeve is less than the thickness of the bridge deck, meaning the steel sleeve is recessed within the bridge deck, forming a blind-hole slot for quick insertion and mating with the connecting studs. Specifically, the top of the connecting stud is formed into a conical or frustum-shaped anchor head 2211, and a cross-shaped expansion joint 2212 is cut. This cross-shaped expansion joint makes the anchor head elastic and provides one-way locking performance, specifically, it can be locked into the aforementioned steel sleeve, as described above. Figure 15 .

[0068] T-shaped connecting steel plates 30 are installed at the splice joints between two unreinforced UHPC bridge decks. These T-shaped connecting steel plates are steel components with a T-shaped cross-section and a wall thickness of 1 mm or 2 mm. (Refer to...) Figure 6 It has a vertical part and a horizontal part. The vertical part is used to fill the gap between two adjacent bridge decks and to make the splice joint seamless through welding during installation, which can effectively prevent water seepage and corrosion. Bolt holes 31 are provided on the horizontal part. The T-shaped connecting steel plate passes through the bolt holes and the corresponding connecting studs 221 are inserted. Under the action of the T-shaped connecting steel plate, the splice joint gap is treated.

[0069] Prefabrication process of assembled unreinforced UHPC bridge deck:

[0070] Step 1: Stamp or weld the required constraint shell, and weld the steel sleeve and studs into the constraint shell. After welding, drill holes in the base plate where the steel sleeve is located to form a through hole running vertically.

[0071] Step 2: Ultra-high performance concrete (UHPC) is poured into a confined shell with welded small-diameter steel sleeves and studs, and steel lifting rings are pre-embedded. It is then sent into a steam curing kiln for steam curing until the UHPC hardens, forming a precast UHPC paving panel without steel reinforcement (2); In this embodiment, galvanized steel fiber is mixed into the UHPC.

[0072] The purpose of the aforementioned embedded steel lifting rings is to provide lifting points for hoisting. Other alternative methods can also be used in the design, which will not be elaborated here.

[0073] The specific construction process is as follows:

[0074] refer to Figures 9 to 12 The series of steps shown introduces a forward installation method: the steps of this rapid assembly method are as follows:

[0075] S1. Draw lines 21 on the steel bridge mounting surface according to the size of the precast bridge deck. The lines include lines along the bridge direction and lines across the bridge direction. After drawing the lines, a square mounting area (mounting unit) is formed. Within the mounting area, the mounting points of the connecting studs are determined and drawn using a special template. The connecting studs 221 are welded to the corresponding mounting points using a special welding gun.

[0076] S2. Install the T-shaped connecting steel plates along the marked lines. Specifically, each T-shaped connecting steel plate spans two unreinforced UHPC bridge decks, thus forming a corresponding boundary around each installation area.

[0077] S3. Apply bonding mortar or other adhesive to the installation area on the steel bridge deck. Install the precast bridge deck panel along the connecting studs 221, ensuring that each connecting stud corresponds to a steel sleeve. Tighten with fastening nuts. After tightening, the installation of one unreinforced UHPC bridge deck panel is complete, and the installation of the next panel begins. After all unreinforced UHPC bridge deck panels are installed, weld at the joints and cut off any exposed portions of the embedded steel lifting rings on the bridge deck panels.

[0078] S4, After the above-mentioned splice joints are welded, the unreinforced UHPC bridge deck and the T-shaped connecting steel plate form a single unit. Figure 13 Finally, asphalt was laid on the bridge surface to form a 40-meter asphalt pavement. Figure 14 .

[0079] As another implementation method, a reverse installation method.

[0080] S1 marks lines on the steel bridge mounting surface according to the dimensions of the unreinforced UHPC bridge deck. The lines are drawn in the longitudinal and transverse directions of the bridge. After the lines are drawn, a square mounting area is formed. Within this mounting area, the mounting points of the connecting studs are determined and marked using a special template. The connecting studs are then welded to the corresponding mounting points using a special welding gun.

[0081] S2 then installs the T-shaped connecting steel plates along the marked lines. Specifically, each T-shaped connecting steel plate spans two unreinforced UHPC bridge decks, forming a corresponding boundary around each installation area.

[0082] S3 applies adhesive mortar or other bonding agents / materials to the installation area on the steel bridge deck. Then, the unreinforced UHPC bridge deck panels are reverse-clamped and installed along the connecting studs, with the bottom plate of the constraint shell facing upwards, onto the steel bridge. A small amount of adhesive mortar is sprayed before clamping, ensuring a one-to-one correspondence between the connecting studs and steel sleeves. The panels are then tightened with nuts. After tightening, one unreinforced UHPC bridge deck panel is installed, and the installation of the next panel begins. Once all unreinforced UHPC bridge deck panels are installed, welding is performed at the joints.

[0083] S4. After the welding at the joints is completed, the unreinforced UHPC bridge deck and the T-shaped connecting steel plate become one unit. Finally, asphalt paving can be carried out on the bridge deck.

[0084] This assembly process eliminates the need for on-site UHPC pouring and steam curing, fully leveraging the advantages of UHPC materials and reducing construction difficulty and material usage.

[0085] At the joint of the unreinforced UHPC bridge deck, the connecting studs pass through both the unreinforced UHPC bridge deck and the T-shaped connecting steel plate. Here, the T-shaped connecting steel plate plays a role in positioning and correcting the joint, making the joint neat and uniform.

[0086] The UHPC bridge deck without reinforcement is mechanically fastened to the steel bridge, and the T-shaped connecting steel plate is welded to the side of the constraint shell as a whole, eliminating the traditional casting connection method. The connection strength and splicing quality are higher, and it can withstand not only the positive bending moment of the bridge but also the negative bending moment. It can also prevent problems such as cracking in the later stage, and give full play to the advantages of UHPC's high durability.

[0087] In this technology, UHPC is prefabricated in a constrained shell and steam-cured in the factory, resulting in good product consistency and resistance to cracking.

[0088] This invention avoids the complex on-site casting process in traditional beam construction, fully leverages the high durability of UHPC, solves the problems of low construction efficiency and poor structural accuracy in traditional steel-UHPC bridge structures, and addresses the issue of side cracking of UHPC slabs in the later stages of traditional casting processes. It simplifies the process, improves efficiency, and increases structural reliability.

[0089] Example 2

[0090] refer to Figure 4 and Figure 5 In this embodiment, the precast bridge deck has been modified. In this embodiment, the constraint shell 10' is rectangular, and longitudinal and transverse partitions 11' are placed and welded inside the constraint shell. The partitions divide the internal space of the constraint shell into several grid-shaped spaces 12', with a cross support frame 13' placed at each space. These cross support frames and partitions improve the overall strength of the precast bridge deck, especially after filling with ultra-high performance concrete, resulting in enhanced overall tensile and compressive strength. While the spaces in the example figure appear dense, in reality, due to the large overall size of the precast wall panel (several meters in length and width), the size of each space can be as large as tens of centimeters; therefore, the presence of the cross support frame is particularly necessary.

[0091] The aforementioned cross support frame can be fixed to the partition or constraint shell by welding.

[0092] In this embodiment, the steel sleeve 111' is set at the intersection of the longitudinal and transverse partitions, which is of positive significance for ensuring installation strength.

[0093] In this embodiment, the constraint shell does not have a bottom surface; that is, there is no bottom surface. In other words, the installation of the steel sleeve in this embodiment is not based on a bottom surface, but on the partition plate.

[0094] Example 3

[0095] A novel precast bridge deck, reference Figure 7 and Figure 8 The bridge deck features pre-welded steel fibers 14' arranged in the same direction on its partitions. These fibers are horizontally inserted through each space, and their ends are fixed to the partitions or the sidewalls of the constraint shell by laser spot welding. After pouring ultra-high performance concrete, the concrete and steel fibers mix to form a precast bridge deck that is more impact- and tensile resistant. This structure allows for the easy fabrication of larger bridge decks, such as those exceeding 10 meters in length.

[0096] in Figure 7 It is an improvement based on Example 1.

[0097] Figure 8 It is an improvement based on Example 2, and the cross support frame is omitted.

[0098] The extra-long bridge deck, under the combined constraint of the confined shell and the internal concrete and steel fibers, has comprehensive properties that make it less prone to cracking and resistant to pressure and tension.

[0099] To ensure clarity of expression, Figure 7 and Figure 8The figure only shows a sparse representation of steel fibers; in reality, the density of steel fibers is much greater than that shown in the figure.

[0100] Ideally, the spacing between steel fibers should be maintained between 10-30 mm. Too sparse a spacing is not conducive to improving tensile strength, while too dense a spacing is not conducive to the filling of ultra-high performance concrete.

[0101] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements to the present invention by those skilled in the art should fall within the protection scope defined by the claims of the present invention.

Claims

1. The prefabricated, unreinforced UHPC bridge deck is an integral panel prefabricated from a restraint shell and ultra-high performance concrete filling, forming a steel-concrete structure. The restraint shell is formed by sheet metal cutting, bending, and welding. Its characteristic is that... The constraint shell is a groove-shaped structure consisting of a bottom surface and four sides, with an open top. The bottom surface, serving as the mounting surface, has a stamped concave-convex structure, and steel sleeves and studs are welded to the bottom surface. The constraint shell has at least a circumferentially enclosing frame structure. The enclosing plate is welded from high-strength steel plates, providing constraint during the forming stage for the ultra-high performance concrete and providing constraint during the installation stage when the internal ultra-high performance concrete is subjected to compression and tension. At least one mounting perforation is provided inside the constraint shell, and the steel sleeve containing the mounting perforation is vertically fixed to the bottom surface extending from the enclosing plate. It penetrates through the base plate; the studs are vertically welded to the base plate, and the ultra-high performance concrete is poured to form an assembled unreinforced UHPC precast bridge deck with the constraint shell, and the strength of the ultra-high performance concrete is 120-150MPa. The upper and lower surfaces of the integrally formed assembled unreinforced UHPC precast bridge deck have flat planes; the two ends of the steel fibers are fixed to the side wall of the constraint shell by laser spot welding, and the spacing between the steel fibers is maintained between 10-30 mm. The steel fibers are arranged in the same direction, and the length of the assembled unreinforced UHPC precast bridge deck exceeds 10 meters.

2. A rapid assembly method for prefabricated unreinforced UHPC bridge decks, characterized in that, Extensive use of prefabricated, unreinforced UHPC bridge deck panels. These prefabricated, unreinforced UHPC bridge deck panels are integral panels prefabricated from a constraint shell and filled with ultra-high performance concrete, forming a reinforced concrete structure. The constraint shell is formed by sheet metal cutting, bending, and welding. This constraint shell is a channel-shaped structure consisting of a bottom surface and four sides, with an open top. The bottom surface, serving as the mounting surface, has a stamped concave-convex structure, and steel sleeves and studs are welded to the bottom surface. The constraint shell has at least a circumferentially enclosing frame structure. The enclosing panels are welded from high-strength steel plates. During the forming stage, it provides constraint for the forming of the ultra-high performance concrete; during the installation stage, it provides constraint when the internal ultra-high performance concrete is subjected to compression and tension. At least within the constraint shell... The section is equipped with mounting holes, and the steel sleeve containing these mounting holes is vertically fixed to the bottom surface extending from the enclosure plate and penetrates the bottom plate; the studs are vertically welded to the bottom plate, and ultra-high performance concrete is poured to form an assembled unreinforced UHPC precast bridge deck with the constraint shell, and the strength of the ultra-high performance concrete is 120-150MPa. The upper and lower surfaces of this integrally formed assembled unreinforced UHPC precast bridge deck have flat planes; the two ends of the steel fibers are fixed to the side wall of the constraint shell by laser spot welding, and the spacing between the steel fibers is maintained between 10-30 mm. The steel fibers are arranged in the same direction. The length of this assembled unreinforced UHPC precast bridge deck exceeds 10 meters, and the following steps are performed: S1. According to the dimensions of the prefabricated unreinforced UHPC bridge deck, lines are drawn on the steel bridge mounting surface. The lines are drawn in the longitudinal and transverse directions of the bridge. After the lines are drawn, multiple square installation areas are formed. Within the installation area, the installation points of the connecting studs are determined and drawn using a special template. The connecting studs are welded to the corresponding installation points on the steel bridge mounting surface. The connecting studs are vertically located at the welding position, and the upper half of the connecting studs is a threaded section. S2. Install the T-shaped connecting steel plate along the marked line. The T-shaped connecting steel plate has a vertical part and a horizontal part. The vertical part is used to fill the gap between two adjacent bridge decks and the splice is seamlessly treated by welding during installation. Bolt holes are provided on the horizontal part, and the corresponding connecting studs are inserted into the T-shaped connecting steel plate through the bolt holes. S3. Apply bonding mortar or other adhesives or bonding materials to the installation area. Place the prefabricated unreinforced UHPC bridge panel from top to bottom in the installation area, ensuring that the connecting studs correspond one-to-one with the steel sleeves, and ensuring that the steel fibers are regularly arranged in the direction of the bridge. During installation, the connecting studs pass through the steel sleeves from bottom to top and are tightened with fastening nuts before installing the next prefabricated unreinforced UHPC bridge panel. After all prefabricated unreinforced UHPC bridge panels are installed, weld at the joints and cut off the exposed parts of the embedded steel lifting rings on the prefabricated unreinforced UHPC bridge panels. S4, and finally asphalt paving is carried out on the bridge surface to form an asphalt road.

3. A rapid assembly method for prefabricated unreinforced UHPC bridge decks, characterized in that, Extensive use of prefabricated, unreinforced UHPC bridge deck panels. These prefabricated, unreinforced UHPC bridge deck panels are integral panels prefabricated from a constraint shell and filled with ultra-high performance concrete, forming a reinforced concrete structure. The constraint shell is formed by sheet metal cutting, bending, and welding. This constraint shell is a channel-shaped structure consisting of a bottom surface and four sides, with an open top. The bottom surface, serving as the mounting surface, has a stamped concave-convex structure, and steel sleeves and studs are welded to the bottom surface. The constraint shell has at least a circumferentially enclosing frame structure. The enclosing panels are welded from high-strength steel plates. During the forming stage, it provides constraint for the forming of the ultra-high performance concrete; during the installation stage, it provides constraint when the internal ultra-high performance concrete is subjected to compression and tension. At least within the constraint shell... The section is equipped with mounting holes, and the steel sleeve containing these mounting holes is vertically fixed to the bottom surface extending from the enclosure plate and penetrates the bottom plate; the studs are vertically welded to the bottom plate, and ultra-high performance concrete is poured to form an assembled unreinforced UHPC precast bridge deck with the constraint shell, and the strength of the ultra-high performance concrete is 120-150MPa. The upper and lower surfaces of this integrally formed assembled unreinforced UHPC precast bridge deck have flat planes; the two ends of the steel fibers are fixed to the side wall of the constraint shell by laser spot welding, and the spacing between the steel fibers is maintained between 10-30 mm. The steel fibers are arranged in the same direction. The length of this assembled unreinforced UHPC precast bridge deck exceeds 10 meters, and the following steps are performed: S1. Draw lines on the steel bridge installation surface according to the dimensions of the prefabricated unreinforced UHPC bridge deck. The lines include lines along the bridge direction and lines in the transverse direction. After drawing the lines, multiple square installation areas are formed. Within the installation area, the installation points of the connecting studs are determined and drawn, and the connecting studs are welded to the corresponding installation points. S2. Then, the T-shaped connecting steel plate is installed along the marked line. The T-shaped connecting steel plate has a vertical part and a horizontal part. The vertical part is used to fill the gap between two adjacent bridge decks and the splice is seamlessly treated by welding during installation. Bolt holes are provided on the horizontal part, and the corresponding connecting studs are inserted into the T-shaped connecting steel plate through the bolt holes. S3. Apply bonding mortar or other adhesive to the installation area. Then, install the prefabricated unreinforced UHPC bridge deck panels in reverse, along the connecting studs. Ensure each connecting stud corresponds to a steel sleeve, and that the steel fibers are regularly arranged in the direction of the bridge. Tighten with nuts. Then proceed with the installation of the next prefabricated unreinforced UHPC bridge deck panel. After all prefabricated unreinforced UHPC bridge deck panels are installed, weld at the joints. S4, asphalt paving is being carried out on the bridge surface.

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