Construction method of multi-span hole assembly type cover plate small bridge and culvert structure

Abstract

The invention belongs to the technical field of highway bridge and culvert engineering, and discloses a multi-span hole assembly type cover plate small bridge and culvert structure construction method which is characterized in that side walls, middle walls and cover plates are transported to a construction site to be assembled after being prefabricated, so that site formwork erecting work is effectively reduced, the construction process is simplified, and the construction efficiency is improved; the connection strength and the structural stability are improved through a grouting method, and then the problem of insufficient grouting of a bedding method is further solved through a secondary grouting method; the pre-embedded steel bar groups of the adjacent cover plates are welded and connected, and by utilizing an equivalent load preloading pre-deformation method in advance, cast-in-place connection areas can bear more uniform stress distribution after being fixedly connected, the stress state in the service stage tends to be more balanced, the crack initiation risk is reduced, and the overall stability and durability of the structure are improved; rigid connection is formed between the adjacent cover plates and the middle wall, the risks of cover plate damage, slab staggering and reflection cracks caused by displacement or looseness of the abutted seam are reduced, and the structural safety and the service life of the bridge and culvert are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of highway bridge and culvert engineering, and in particular to a construction method of a multi-span assembled cover-plate small bridge and culvert structure. Background Art

[0002] Culverts, as indispensable structures, play a crucial role in highway construction. Their primary function is to ensure smooth surface traffic while enabling effective underground drainage. Culverts come in a variety of structural forms, with circular pipe culverts, box culverts, and slab culverts being common. Slab culverts are widely used due to their ease of construction and high drainage capacity. In particular, the simply supported slab can be prefabricated in a factory, significantly reducing on-site work, accelerating construction progress, and improving overall quality.

[0003] At present, in culverts with cover plate structures, except for the cover plate structure which is mostly prefabricated, the rest of the parts (such as side walls, middle walls, etc.) usually still need to be cast on site. Due to the complex process and numerous steps of cast-in-place construction, not only does it lead to a long construction period, but it also requires a large amount of formwork support, which increases construction costs and has a significant impact on the overall construction progress. In addition, in multi-span cover plate culvert structures, in order to meet the structural requirements of the cover plate being shelved and not falling beams, the middle wall is usually designed to be thicker, which not only has a certain impact on the water-passing capacity of the culvert, but also easily forms silt in front of the middle wall. At the same time, multi-span cover plate structures usually adopt a simply supported form, which is prone to reflective cracks, and the cover plate is easy to shift, which not only affects the road driving quality, but also accelerates the aging of the road surface and reduces the service life of the road surface.

[0004] Therefore, there is an urgent need for a construction method for a multi-span assembled cover small bridge culvert structure to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a construction method for a multi-span assembled cover plate small bridge culvert structure.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] The construction method of a multi-span assembled cover-plate small bridge culvert structure includes the following steps:

[0008] S1: The base is cast at the construction site using an integral cast-in-place process, and side wall positioning holes, side wall grouting holes, middle wall positioning holes, and middle wall grouting holes are opened on the base, and are arranged along the length direction of the base; the side wall positioning holes are located on both sides of the base, the middle wall positioning hole is located between the side wall positioning holes on both sides, the side wall grouting hole is connected to multiple side wall positioning holes, and the middle wall grouting hole is connected to multiple middle wall positioning holes;

[0009] S2: Prefabricate the side walls, middle wall and cover plate, and transport them to the construction site for use; a side wall positioning piece is provided at the bottom of the side wall; an upper boss extending in the width direction of the base is provided at the top of the middle wall, and a lower boss extending in the width direction of the base is provided at its bottom; a plurality of cover plate positioning steel bars are provided on both sides of the upper surface of the upper boss along the length direction of the base, and a middle wall positioning piece is provided at the bottom of the lower boss; the cover plate includes a cover plate body and an embedded steel bar assembly, a cover plate positioning hole is provided on the lower surface of the cover plate body, and the embedded steel bar assembly is provided inside the cover plate body, and partially extends out of both sides of the cover plate body along the width direction of the base;

[0010] S3: Assemble the side walls on both sides of the base, and insert and match the side wall positioning pieces with the corresponding side wall positioning holes; arrange the middle wall between the side walls on both sides, and insert and match the middle wall positioning pieces with the middle wall positioning holes;

[0011] S4: using a grouting method, grouting is performed into the side wall positioning holes and the middle wall positioning holes through the side wall grouting holes and the middle wall grouting holes to perform preliminary anchoring of the side wall and the middle wall;

[0012] S5: After the initial grouting solidifies, a secondary grouting is performed through the side wall grouting holes and the middle wall grouting holes to re-anchor the side wall and the middle wall;

[0013] S6: The cover plate positioning holes of the cover plate are plugged into the cover plate positioning steel bars, and the cover plate is placed on the upper boss and the top of the side wall to complete the positioning; a cast-in-place connection area is reserved on the upper boss between adjacent cover plates;

[0014] S7: After all the cover plates are in place, in each cast-in-place connection area, the embedded steel bar assemblies arranged opposite to each other in adjacent cover plates are welded together;

[0015] S8: Using an equivalent load pre-loading and pre-deformation method, a heavy object is piled on the upper surface of the welded cover plate to be equivalent to a vehicle load;

[0016] S9: pouring concrete in the cast-in-situ connection area to fix the adjacent cover plates and the upper bosses, and performing sufficient vibration compaction and subsequent curing after the concrete pouring;

[0017] S10: After the cast-in-situ connection area solidifies, the heavy object on the upper surface of the cover plate is removed.

[0018] Furthermore, the upper surface of the base is provided with a side wall positioning groove and a middle wall positioning groove along its length direction, the side wall positioning groove is provided with the side wall positioning hole, and the middle wall positioning groove is provided with the middle wall positioning hole.

[0019] Furthermore, the embedded steel bar assembly includes an upper main steel bar and a lower main steel bar, which are respectively arranged at the upper and lower parts of the cover plate body in relative positions, and are evenly spaced along the width direction of the base, and can both extend out of the cover plate body along the width direction of the base. The upper main steel bars and the lower main steel bars arranged relatively in positions on adjacent cover plates on each upper boss are staggered, and the relative upper main steel bars are welded one by one to form a negative bending moment zone in the cast-in-place connection area.

[0020] Furthermore, the embedded steel bar assembly also includes upper structural steel bars and lower structural steel bars, the upper structural steel bars are arranged between the upper main steel bars and the upper surface of the cover body, and the lower structural steel bars are arranged between the lower main steel bars and the lower surface of the cover body; the two are arranged at intervals along the length direction of the base, and are densely arranged near the cover positioning hole position on the cover body.

[0021] Furthermore, cast-in-place area stirrups and cast-in-place area structural steel bars are provided in the cast-in-place connection area. The cast-in-place area stirrups are vertically closed around the upper main steel bars and the lower main steel bars to form a closed stirrup frame. The cast-in-place area structural steel bars are arranged in plurality along the length direction of the base.

[0022] Furthermore, the upper surface of the cover plate is flush with the upper surface of the cast-in-place connection area.

[0023] Furthermore, the annular gap between each of the cover plate positioning holes and the cover plate positioning steel bars can be sealed by grouting.

[0024] Furthermore, a cover plate positioning groove is provided on a side of the top end of each side wall close to the middle wall along the length direction of the base.

[0025] Furthermore, the upper surface of each upper boss is configured as a rough surface; and / or

[0026] Both side end surfaces of each cover plate are configured as the rough surface.

[0027] Furthermore, a waterproof layer is provided between the cover plate and the side wall; and / or

[0028] The waterproof layer is arranged between the cover plate and the upper boss of the middle wall.

[0029] Beneficial effects of the present invention:

[0030] The present invention provides a multi-span assembled cover-plate small bridge culvert structure construction method, which prefabricates the side walls, middle walls and cover plates and transports them to the construction site for assembly, effectively reducing on-site formwork support work, simplifying the construction process and improving construction efficiency; utilizing the grouting method to effectively improve the connection strength and structural stability of the middle wall and side walls and the base, and compensating for minor deviations that may occur during the installation of components; further compensating for the problem of insufficient grouting by the grouting method through the secondary grouting method, filling minor gaps, avoiding hollowing or de-spacing at the structural connection, and improving the connection reliability and bearing capacity; welding the embedded steel bars of adjacent cover plates together, utilizing the equivalent load pre-loading pre-deformation method, and using heavy The equivalent vehicle load weight is used to load the adjacent cover plates that have been welded together in advance, and then the concrete is poured, so that the cast-in-place connection area can withstand more uniform stress distribution after being fixed, and the stress state in the service stage is more balanced, which effectively weakens the tensile stress of the post-cast zone, reduces the risk of crack initiation, and improves the overall stability and durability of the structure. A rigid connection is formed between the adjacent cover plates and the middle wall, and the adjacent cover plates are transformed from a simply supported structure to a continuous structure, which improves the overall continuity of the structure, effectively resists the differential settlement and small displacement caused by traffic loads, reduces the risk of cover plate 4 damage, misalignment and reflective cracks caused by displacement or loosening of the joints, and ensures the structural safety and service life of the bridge culvert. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a structural diagram of a multi-span assembled cover plate small bridge culvert structure of the present invention;

[0032] Figure 2 This is an exploded view of the multi-span assembled cover plate small bridge culvert structure of the present invention;

[0033] Figure 3 This is a front view of a multi-span assembled cover plate small bridge culvert structure according to the present invention;

[0034] Figure 4 It is a structural schematic diagram of the middle wall and cover plate of the present invention;

[0035] Figure 5 is a front view of the connection between the middle wall and the cover plate of the present invention;

[0036] Figure 6 It is a top view of the connection between the middle wall and the cover plate of the present invention.

[0037] In the picture:

[0038] 1. Base; 11. Side wall positioning hole; 12. Side wall positioning groove; 13. Middle wall positioning groove; 14. Middle wall positioning hole; 15. Side wall grouting hole; 16. Middle wall grouting hole;

[0039] 2. Side wall; 21. Side wall positioning piece; 22. Cover plate positioning groove;

[0040] 3. Middle wall; 31. Upper boss; 32. Cover plate positioning reinforcement; 33. Lower boss; 34. Middle wall positioning piece; 35. Middle wall main reinforcement;

[0041] 4. Cover plate; 41. Cover plate positioning hole; 42. Cover plate body; 43. Embedded steel bar assembly; 431. Upper main steel bar; 432. Upper structural steel bar; 433. Lower main steel bar; 434. Lower structural steel bar;

[0042] 5. Cast-in-place connection area; 51. Stirrups in cast-in-place area; 52. Structural reinforcement in cast-in-place area. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It will be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all structures.

[0044] In the description of the present invention, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention in specific circumstances.

[0045] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Furthermore, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0046] In the description of this embodiment, terms such as "upper," "lower," "left," and "right" are used to refer to positions or locations based on those shown in the accompanying drawings. These terms are intended solely to facilitate description and simplify operation, and are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0047] Please refer to Figures 1 to 6 As shown, this embodiment discloses a construction method for a multi-span assembled cover plate small bridge culvert structure, comprising the following steps:

[0048] S1: The base 1 is cast at the construction site using an integral cast-in-place process. Side wall positioning holes 11, side wall grouting holes 15, middle wall positioning holes 14, and middle wall grouting holes 16 are opened on the base 1 and arranged along the length of the base 1. The side wall positioning holes 11 are located on both sides of the base 1, the middle wall positioning holes 14 are located between the side wall positioning holes 11 on both sides, the side wall grouting holes 15 are connected to the multiple side wall positioning holes 11, and the middle wall grouting holes 16 are connected to the multiple middle wall positioning holes 14.

[0049] S2: Prefabricate the side walls 2, middle wall 3 and cover plate 4 and transport them to the construction site for use; a side wall positioning piece 21 is provided at the bottom of the side wall 2; an upper boss 31 extending along the width direction of the base 1 is provided at the top of the middle wall 3, and a lower boss 33 extending along the width direction of the base 1 is provided at its bottom; a plurality of cover plate positioning steel bars 32 are provided on both sides of the upper surface of the upper boss 31 along the length direction of the base 1, and a middle wall positioning piece 34 is provided at the bottom of the lower boss 33; the cover plate 4 includes a cover plate body 42 and an embedded steel bar assembly 43, a cover plate positioning hole 41 is provided on the lower surface of the cover plate body 42, and the embedded steel bar assembly 43 is arranged inside the cover plate body 42, and partially extends out of both sides of the cover plate body 42 along the width direction of the base 1;

[0050] S3: Assemble the side walls 2 on both sides of the base 1, and insert and mate the side wall positioning pieces 21 with the corresponding side wall positioning holes 11; arrange the middle wall 3 between the two side walls 2, and insert and mate the middle wall positioning pieces 34 with the middle wall positioning holes 14;

[0051] S4: Using the grouting method, grouting is injected into the side wall positioning holes 11 and the middle wall positioning holes 14 through the side wall grouting holes 15 and the middle wall grouting holes 16 to perform preliminary anchoring of the side wall 2 and the middle wall 3;

[0052] S5: After the initial grouting solidifies, a secondary grouting is performed through the side wall grouting holes 15 and the middle wall grouting holes 16 to re-anchor the side wall 2 and the middle wall 3;

[0053] S6: The cover plate positioning holes 41 of the cover plate 4 are plugged into the cover plate positioning steel bars 32, and the cover plate 4 is placed on the upper boss 31 and the top of the side wall 2 to complete the positioning; a cast-in-place connection area 5 is reserved between adjacent cover plates 4 on the upper boss 31;

[0054] S7: After all the cover plates 4 are in place, the embedded steel bar assemblies 43 arranged opposite to each other in the adjacent cover plates 4 are welded together in each cast-in-situ connection area 5;

[0055] S8: Using the equivalent load pre-loading pre-deformation method, load heavy objects on the upper surface of the welded cover plate 4 to the equivalent vehicle load;

[0056] S9: pouring concrete in the cast-in-situ connection area 5 to securely connect the adjacent cover plates 4 and the upper bosses 31. After pouring the concrete, fully vibrate and compact it, and then perform post-curing.

[0057] S10: After the cast-in-situ connection area 5 solidifies, remove the heavy objects on the upper surface of the cover plate 4.

[0058] The base 1 is cast in place as a whole, and the side walls 2, middle wall 3, and cover plate 4 are all prefabricated components. By prefabricating the side walls 2, middle wall 3, and cover plate 4 and then transporting them to the construction site for assembly, the on-site formwork support work is effectively reduced, the construction process is simplified, and construction efficiency is improved. Positioning components are provided at the corresponding connection points between the base 1 and the side walls 2 and middle wall 3 to ensure rapid alignment and precise connection of the components during installation, significantly shortening the construction period. By providing an upper boss 31 and a lower boss 33 extending along the width of the base 1 at the top and bottom ends of the middle wall 3, respectively, the contact area between the middle wall 3 and the cover plate 4, as well as between the middle wall 3 and the base 1, is increased, thereby improving the support stability of the middle wall 3. This structure of the middle wall 3 can appropriately reduce the wall thickness of the middle wall 3, thereby effectively reducing its water-blocking area in water, reducing the impact on the water-passing section, improving the drainage capacity of the culvert, and reducing costs to maintain smooth drainage. By plugging and fitting the cover plate positioning holes 41 with the cover plate positioning steel bars 32, combined with the pouring of concrete in the cast-in-place connection area 5 between adjacent cover plates 4, a rigid connection is formed between the adjacent cover plates 4 and the middle wall 3, so that the adjacent cover plates 4 are transformed from a simply supported structure to a continuous structure, thereby improving the overall continuity of the structure, effectively resisting the differential settlement and micro-displacement caused by traffic loads, reducing the risk of damage, dislocation and reflective cracks of the cover plates 4 caused by displacement or loosening at the joints, and ensuring the structural safety and service life of the bridge culvert.

[0059] By adopting the grouting method, grouting is injected from the side wall grouting holes 15 and the middle wall grouting holes 16 into the side wall positioning holes 11 and the middle wall positioning holes 14 to perform preliminary anchoring of the side walls 2 and the middle wall 3. By injecting high-fluidity slurry, the gaps between the components and the hole walls are filled, so that a dense and reliable embedded connection is formed between the side wall positioning pieces 21 and the middle wall positioning pieces 34 and the base 1. This can not only effectively improve the connection strength and structural stability, and compensate for the slight deviations that may occur during the installation of the components, but also has the advantages of simple construction, strong adaptability, and good durability, which helps to improve the overall structure's stress performance and long-term service safety. After the structure is fixed using the grouting method, the secondary grouting method is used to inject grouting again from the reserved side wall grouting holes 15 and the middle wall grouting holes 16 to further fill and compact any gaps that may exist. The secondary grouting method can further compensate for the problem of insufficient grouting in the grouting method, fill small gaps, avoid hollowing or degassing at the structural connection, and improve the connection reliability and bearing capacity.

[0060] By adopting the equivalent load pre-loading pre-deformation method, heavy objects are piled on to simulate the equivalent vehicle load, so that the cover plate 4 is subjected to stress in advance. After that, concrete is poured until the adjacent cover plates 4 are stably connected. The heavy objects are then unloaded. At this time, the cover plates 4 of the continuous structure have undergone reverse deformation, so that the cast-in-place connection area 5 can withstand a more uniform stress distribution after being fixed. Therefore, the equivalent load pre-loading pre-deformation method makes the stress state of the cast-in-place connection area 5 more balanced during the service phase after concrete pouring, effectively weakening the tensile stress in the post-cast zone, reducing the risk of crack initiation, and improving the overall stability and durability of the structure. The heavy objects can be, but are not limited to, sandbags or water bags, etc., and are not specifically limited here.

[0061] Optionally, the side wall positioning member 21 can adopt the side wall 2 positioning steel bar, which is arranged in the side wall 2 along the vertical direction and extends out of the bottom of the side wall 2; the middle wall positioning member 34 can adopt the side wall 2 positioning steel bar, which is arranged in the middle wall 3 and can extend out of the bottom of the lower boss 33 of the middle wall 3. The vertically arranged positioning steel bars help to form a continuous force channel between the component and the base 1, optimize the force transmission path of the overall structure, and improve the seismic resistance and durability of the structure.

[0062] Optionally, micro-expansive concrete can be used. Since micro-expansive concrete contains an appropriate amount of expansive components (such as calcium oxide, expansive agents, etc.), it produces a tiny volume expansion in the initial stage of hardening, which can effectively compensate for the volume shrinkage of ordinary concrete caused by drying shrinkage, temperature difference, etc., and help reduce cracks caused by constraints. It is suitable for locations prone to cracking, such as cast-in-place sections and continuous structure connection areas.

[0063] In other embodiments, the middle wall 3 also includes a middle wall main steel bar 35 arranged therein along the vertical direction, and the upper and lower ends of the middle wall main steel bar 35 respectively pass through the upper boss 31 and the lower boss 33 of the middle wall 3: wherein, the part extending from the upper boss 31 is located in the cast-in-place connection area 5 between adjacent cover plates 4, and can form a reliable rigid connection with the cover plates 4 after pouring concrete, thereby enhancing the overall stability between the adjacent cover plates 4; and the part of the main steel bar extending from the lower boss 33 can be inserted into the middle wall positioning hole 14 provided on the base 1 and realize an embedded connection, further improving the connection strength and structural stability between the middle wall 3 and the base 1.

[0064] Combine Figure 2 and Figure 3 As shown, in some embodiments, a side wall positioning groove 12 and a middle wall positioning groove 13 are provided on the upper surface of the base 1 along its length direction, a side wall positioning hole 11 is provided in the side wall positioning groove 12, and a middle wall positioning hole 14 is provided in the middle wall positioning groove 13; wherein, the side wall positioning groove 12 and the middle wall positioning groove 13 can facilitate the rapid positioning, alignment and assembly of the side walls 2 and the middle wall 3, thereby allowing the side wall positioning members 21 and the middle wall positioning members 34 to be quickly inserted into the side wall positioning holes 11 and the middle wall positioning holes 14, and realize embedded connection.

[0065] Combine Figure 5 and Figure 6 As shown, specifically, the embedded steel bar assembly 43 includes an upper main steel bar 431 and a lower main steel bar 433, which are respectively arranged at the upper and lower parts of the cover plate body 42 in relative positions, and are evenly spaced along the width direction of the base 1, and can both extend out of the cover plate body 42 along the width direction of the base 1. The upper main steel bars 431 and the lower main steel bars 433 arranged relatively on the adjacent cover plates 4 on each upper boss 31 are staggered, and the relative upper main steel bars 431 are welded one by one to form a negative bending moment zone in the cast-in-place connection area 5; wherein, the upper main steel bars 431 and the lower main steel bars The ribs 433 are respectively arranged at the upper and lower edges of the cover plate body 42 to form an effective load-bearing lever arm, which can fully exert its bending resistance; the upper main steel bars 431 and the lower main steel bars 433 both extend outward and can penetrate into the connection area of the adjacent cover plates 4, so that the original simply supported components form a continuous beam structure after casting, thereby improving the structural integrity; and the upper main steel bars 431 and the lower main steel bars 433 that are relatively positioned between the adjacent cover plates 4 on each upper boss 31 are staggered in the cast-in-place connection area 5, which is more convenient for butt welding, is beneficial to the structural continuity formed by the welding of steel bars, and improves the connection strength.

[0066] Furthermore, by welding the upper main reinforcement bars 431 one by one into a single piece within the cast-in-place connection area 5 of the cover plate 4, the adjacent cover plates 4, which are originally simply supported, are structurally formed into a continuous beam. The continuous connection of the upper main reinforcement bars 431 within the cast-in-place connection area 5 creates an effective negative moment zone when loaded at mid-span, thereby improving the structure's flexural rigidity and overall bearing capacity. In this case, the lower main reinforcement bars 433 can be welded in a staggered manner, for example, connecting every other bar. The specific number of staggered connections is not specified herein, thereby reducing construction difficulty, facilitating construction, and accelerating the construction schedule.

[0067] The embedded steel bar assembly 43 also includes an upper structural steel bar 432 and a lower structural steel bar 434. The upper structural steel bar 432 is arranged between the upper main steel bar 431 and the upper surface of the cover body 42, and the lower structural steel bar 434 is arranged between the lower main steel bar 433 and the lower surface of the cover body 42. The two are arranged at intervals along the length direction of the base 1, and are densely arranged near the cover body 42 near the cover positioning hole 41. Among them, the upper structural steel bar 432 and the lower structural steel bar 434 are close to the surface of the cover body 42, which can be controlled. It can control surface cracks caused by temperature difference, shrinkage, etc., and play a role in controlling crack distribution; since the cover plate positioning hole 41 is opened on the lower surface of the cover plate 4, its surrounding area is weak, which will cause stress concentration, especially under the stress of vehicle load, temperature difference or shrinkage, it is more likely to form micro cracks, so a plurality of upper structural steel bars 432 and a plurality of lower structural steel bars 434 are densely arranged near the cover plate positioning hole 41 on the cover plate body 42, which can effectively strengthen the opening position of the cover plate 4 and enhance the crack resistance of the opening part of the cover plate 4.

[0068] In order to enhance the connection strength of the cast-in-place connection area 5, in some embodiments, cast-in-place connection area 5 is provided with cast-in-place stirrups 51 and cast-in-place structural steel bars 52. The cast-in-place stirrups 51 are vertically closed around the upper main steel bars 431 and the lower main steel bars 433 to form a closed stirrup frame. Multiple cast-in-place structural steel bars 52 are provided along the length direction of the base 1. Among them, arranging the cast-in-place stirrups 51 around the upper main steel bars 431 and the lower steel bars is beneficial to laterally constraining the concrete and preventing shear failure or oblique cracks in the concrete due to shear force, negative bending moment or load concentration. In addition, the cast-in-place connection area 5 is a negative bending moment concentration area of the bridge deck (such as the pier top). The upper main steel bar 431 is subjected to tension and the structure is prone to cracking. The closed stirrups can limit the lateral displacement of the upper main steel bar 431, prevent it from buckling, improve the stiffness and ductility of the negative bending moment area, and delay damage. Arranging the cast-in-place structural steel bars 52 along the length direction of the base 1 helps to share secondary stresses such as early temperature shrinkage and drying shrinkage.

[0069] In some embodiments, the upper surface of the cover plate 4 is flush with the upper surface of the cast-in-place connection area 5, so that the cover plate 4 and the cast-in-place connection area 5 form a continuous and unified top surface, avoiding height misalignment, which is beneficial to the coordination of the overall stress and deformation of the structure, and can also reduce the risk of vehicle impact loads or local cracking of concrete caused by height differences.

[0070] In some embodiments, the annular gaps between each cover plate positioning hole 41 and the cover plate positioning steel bars 32 can be sealed by grouting, which can effectively enhance the synergistic effect between the positioning steel bars and the cover plate 4, avoid the risks of hollowing, cracking and water seepage caused by the annular gaps, improve the overall density and anti-seepage performance of the structure, and ensure the durability of the structure; optionally, mortar can be injected into the annular gaps for sealing, which is not specifically limited here.

[0071] In some embodiments, a cover plate positioning groove 22 is provided along the length of the base 1 on the side of the top of each side wall 2 near the center wall 3. This facilitates precise positioning and guiding of the cover plate 4 during installation, improving the stability and assembly accuracy of the cover plate 4 and preventing lateral slippage or positional displacement of the cover plate 4 during installation or service. Furthermore, the cover plate positioning groove 22 increases the contact area between the cover plate 4 and the side wall 2, optimizing the load transfer path and more effectively transferring vertical forces acting on the cover plate 4 to the side wall 2, further enhancing the overall load-bearing performance of the structure. Optionally, the top of the positioning groove is maintained at the same level as the upper surface of the cover plate 4, resulting in a smoother road surface.

[0072] In some embodiments, the upper surface of each upper boss 31 is set to a rough surface; and / or both side end surfaces of each cover plate 4 are set to a rough surface, so that the concrete is more tightly connected to the boss and / or cover plate 4.

[0073] The culvert structure is exposed to the water flow environment for a long time. Water can penetrate through the gaps between the cover plate 4 and the side walls 2 and the middle wall 3, which may corrode the internal concrete or steel bars and induce problems such as rust, carbonization, and freeze-thaw damage. To solve the above problems, a waterproof layer is placed between the cover plate 4 and the side walls 2; and / or a waterproof layer is placed between the cover plate 4 and the upper boss 31 of the middle wall 3; wherein the waterproof layer can effectively block the water seepage path, reduce the risk of moisture inside the structure, and improve the overall service life.

[0074] Optionally, the waterproof layer may be made of, but not limited to, linoleum felt, and the amount of linoleum felt may be provided according to actual conditions and is not specifically limited herein.

[0075] In some embodiments, multiple cover plates 4 can be arranged side by side along the length direction of the base 1. Construction workers can flexibly increase or decrease the number of cover plates 4 according to different culvert lengths or terrain conditions to adapt to various spans and traffic requirements, thereby enhancing the versatility and adaptability of the structure.

[0076] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. The construction method of a multi-span assembled cover small bridge culvert structure is characterized by: The following steps are involved: S1: The base (1) is cast at the construction site using an integral cast-in-place process, and side wall positioning holes (11), side wall grouting holes (15), middle wall positioning holes (14) and middle wall grouting holes (16) are provided on the base (1), and are all arranged along the length direction of the base (1); the side wall positioning holes (11) are located on both sides of the base (1), the middle wall positioning holes (14) are located between the side wall positioning holes (11) on both sides, the side wall grouting holes (15) are connected to a plurality of the side wall positioning holes (11), and the middle wall grouting holes (16) are connected to a plurality of the middle wall positioning holes (14); S2: Prefabricate the side walls (2), the middle wall (3) and the cover plate (4), and transport them to the construction site for use; the side wall (2) is provided with a side wall positioning piece (21) at the bottom; the middle wall (3) is provided with an upper boss (31) extending along the width direction of the base (1) at the top, and a lower boss (33) extending along the width direction of the base (1) at the bottom; a plurality of cover plate positioning steel bars (32) are provided on both sides of the upper surface of the upper boss (31) along the length direction of the base (1), and a middle wall positioning piece (34) is provided at the bottom of the lower boss (33); the cover plate (4) includes a cover plate body (42) and an embedded steel bar assembly (43); a cover plate positioning hole (41) is provided on the lower surface of the cover plate body (42), and the embedded steel bar assembly (43) is arranged inside the cover plate body (42), and partially extends out of both sides of the cover plate body (42) along the width direction of the base (1); S3: Assemble the side walls (2) on both sides of the base (1), and insert and match the side wall positioning pieces (21) with the corresponding side wall positioning holes (11); arrange the middle wall (3) between the side walls (2) on both sides, and insert and match the middle wall positioning pieces (34) with the middle wall positioning holes (14); S4: using the grouting method, grouting is performed into the side wall positioning hole (11) and the middle wall positioning hole (14) through the side wall grouting hole (15) and the middle wall grouting hole (16), thereby performing preliminary anchoring of the side wall (2) and the middle wall (3); S5: After the initial grouting solidifies, a secondary grouting is performed through the side wall grouting holes (15) and the middle wall grouting holes (16) to re-anchor the side wall (2) and the middle wall (3); S6: The cover plate positioning hole (41) of the cover plate (4) is plugged into and matched with the cover plate positioning steel bar (32), and the cover plate (4) is placed on the top of the upper boss (31) and the side wall (2) to complete the positioning; a cast-in-place connection area (5) is reserved on the upper boss (31) between adjacent cover plates (4); S7: After all the cover plates (4) are in place, the embedded steel bar assemblies (43) arranged opposite to each other in the adjacent cover plates (4) are welded together in each cast-in-situ connection area (5); S8: using an equivalent load pre-loading pre-deformation method, loading a heavy object on the upper surface of the welded cover plate (4) to be equivalent to a vehicle load; S9: pouring concrete in the cast-in-situ connection area (5) so that the adjacent cover plates (4) and the upper bosses (31) are fixedly connected, and after pouring the concrete, performing sufficient vibration compaction and subsequent curing; S10: After the cast-in-situ connection area (5) solidifies, the weight on the upper surface of the cover plate (4) is removed.

2. The construction method of a multi-span assembled cover plate small bridge culvert structure according to claim 1 is characterized in that: The upper surface of the base (1) is provided with a side wall positioning groove (12) and a middle wall positioning groove (13) along its length direction, the side wall positioning groove (12) is provided with the side wall positioning hole (11), and the middle wall positioning groove (13) is provided with the middle wall positioning hole (14).

3. The construction method of a multi-span assembled cover plate small bridge and culvert structure according to claim 1 is characterized in that: The embedded steel bar assembly (43) comprises an upper main steel bar (431) and a lower main steel bar (433), which are respectively arranged at the upper and lower parts of the cover plate body (42) in relative positions and are evenly spaced along the width direction of the base (1). Both can extend out of the cover plate body (42) along the width direction of the base (1). The upper main steel bars (431) and the lower main steel bars (433) arranged relatively on the adjacent cover plates (4) on each upper boss (31) are staggered, and the relative upper main steel bars (431) are welded one by one, so that the cast-in-place connection area (5) forms a negative bending moment zone.

4. The construction method of a multi-span assembled cover plate small bridge and culvert structure according to claim 3 is characterized in that: The embedded steel bar assembly (43) further includes an upper structural steel bar (432) and a lower structural steel bar (434), wherein the upper structural steel bar (432) is arranged between the upper main steel bar (431) and the upper surface of the cover plate body (42), and the lower structural steel bar (434) is arranged between the lower main steel bar (433) and the lower surface of the cover plate body (42); the two are arranged at intervals along the length direction of the base (1), and are densely arranged near the cover plate positioning hole (41) on the cover plate body (42).

5. The construction method of a multi-span assembled cover plate small bridge and culvert structure according to claim 4 is characterized in that: The cast-in-situ connection area (5) is provided with cast-in-situ area stirrups (51) and cast-in-situ area structural steel bars (52). The cast-in-situ area stirrups (51) are vertically closed around the upper main steel bars (431) and the lower main steel bars (433) to form a closed stirrup frame. A plurality of cast-in-situ area structural steel bars (52) are provided along the length direction of the base (1).

6. The construction method of a multi-span assembled cover plate small bridge and culvert structure according to any one of claims 1 to 5, characterized in that: The upper surface of the cover plate (4) is flush with the upper surface of the cast-in-situ connection area (5).

7. The construction method of a multi-span assembled cover-plate small bridge and culvert structure according to any one of claims 1 to 5, characterized in that: The annular gap between each of the cover plate positioning holes (41) and the cover plate positioning steel bars (32) can be sealed by grouting.

8. The construction method of a multi-span assembled cover-plate small bridge and culvert structure according to any one of claims 1 to 5, characterized in that: A cover plate positioning groove (22) is provided on the top of each side wall (2) on one side close to the middle wall (3) along the length direction of the base (1).

9. The construction method of a multi-span assembled cover-plate small bridge and culvert structure according to any one of claims 1 to 5, characterized in that: The upper surface of each upper boss (31) is configured as a rough surface; and / or Both side end surfaces of each cover plate (4) are configured as the rough surfaces.

10. The construction method of a multi-span assembled cover-plate small bridge and culvert structure according to any one of claims 1 to 5, characterized in that: A waterproof layer is provided between the cover plate (4) and the side wall (2); and / or The waterproof layer is disposed between the cover plate (4) and the upper boss (31) of the middle wall (3).

Images