A seamless extended bridge structure suitable for soft soil areas and its construction method

Abstract

A seamless extended bridge structure suitable for soft soil areas includes a main girder, abutments, sunken approach slabs, UHPC (Ultra-High-Pressure Polymer) junction slabs, reinforced pavement layer, ground beam, and precast piles. The main girder is simply supported on supports, and adjacent main girders and the main girder and reinforced pavement layer are connected by UHPC junction slabs. One side of the sunken approach slab overlaps the back of the abutment, and the other side is fixed to the ground beam, which is supported by pile foundations. The reinforced pavement layer includes an expansion / contraction buffer zone above the sunken approach slab and a fixed zone above the ground beam; the expansion / contraction buffer zone is provided with expansion / contraction space by saw cuts, and a sliding layer is provided between it and the sunken approach slab. This scheme connects the bridge deck, UHPC junction slab, and reinforced pavement layer into a single structure using a steel mesh frame. The reinforced pavement layer absorbs the thermal expansion and contraction of the bridge, and the sunken approach slab controls uneven settlement at the bridge abutments, making it particularly suitable for soft soil areas. This disclosure also provides a construction method for a seamless extended bridge with a soft soil deck suitable for soft soil areas, reducing construction difficulty and ensuring performance.

Description

Technical Field

[0001] This invention relates to the technical field of bridge and road-bridge connection construction, specifically to a seamless bridge structure with extended deck suitable for soft soil areas, and provides a construction method for such a structure. Background Technology

[0002] In recent years, simply supported bridges with multiple continuous spans have been widely used in medium and small-span bridges due to their simple structure, convenient construction, and low cost. However, these bridges have a large number of expansion joints, causing frequent vehicle bounces during driving, which not only damages the expansion joints but also reduces driving comfort. Therefore, to reduce the adverse effects of expansion joints, expansion joint-free bridges have become a research hotspot in recent years.

[0003] A seamless extended-deck bridge is a type of bridge with separate beams and a continuous deck, free of expansion joints. It retains the advantages of simple-supported beam bridges (simple stress distribution and easy construction) while also offering the smooth driving experience of continuous beam bridges. However, in the past, when this type of bridge was applied to soft soil areas, uneven settlement at the bridge abutments caused excessive bending forces on the extended deck, making it prone to damage. This meant it couldn't act as a buffer zone to absorb thermal expansion and contraction. If ordinary abutment slabs were used to control settlement, a buffer zone would need to be installed behind the slabs, which not only affected its ability to absorb thermal expansion and contraction but also resulted in excessively long road-bridge connections and significantly increased costs. Therefore, it is necessary to propose a seamless extended-deck bridge structure suitable for soft soil areas, one that is easy to construct and has controllable costs. Summary of the Invention

[0004] The purpose of this invention is to provide a seamless extended bridge deck structure suitable for soft soil areas and to propose a corresponding construction method, thereby effectively solving the problem that traditional seamless extended bridge decks cannot be applied to soft soil areas due to uneven settlement at the bridgehead.

[0005] To address the aforementioned problems, this invention provides a seamless extended bridge structure suitable for soft soil areas, comprising an abutment, a main beam, a sunken approach slab, a UHPC junction slab, a reinforced pavement layer, and a ground beam. The main beam overlaps the near-bridge side of the abutment, and a bridge deck is mounted on the main beam. One end of the sunken approach slab overlaps the near-ground side of the abutment, and the other end connects to the ground beam. The reinforced pavement layer includes an expansion and contraction buffer zone located above the sunken approach slab and a fixed zone connected to the ground beam. A sliding layer connected to the expansion and contraction buffer zone is provided on the upper side of the sunken approach slab. The UHPC junction slab is located on the abutment, with one end connected to the expansion and contraction buffer zone and the other end connected to the bridge deck, making the upper sides of the bridge deck, the UHPC junction slab, and the reinforced pavement layer flush. An asphalt concrete surface layer is poured on the upper sides of the bridge deck, the UHPC junction slab, and the reinforced pavement layer.

[0006] The above-mentioned solution connects the bridge deck, UHPC junction slab, and reinforced pavement layer into a unified structure. On the one hand, it ensures the smoothness of the junction between the bridge deck and the reinforced pavement layer, improving the driving experience. On the other hand, it allows the temperature deformation of the main beam to be directly transferred to the reinforced pavement layer. Since the expansion and contraction buffer zone of the reinforced pavement layer is connected to the sunken approach slab through a sliding layer, the expansion and contraction buffer zone can generate relative displacement with the sunken approach slab, thereby absorbing the displacement caused by the thermal expansion and contraction of the main beam. At the same time, by placing the sunken approach slab below the reinforced pavement layer, it can provide good support for the reinforced pavement layer, not only avoiding the bending problem of the reinforced pavement layer caused by uneven settlement, but also reducing the thickness of the reinforced pavement layer and saving materials.

[0007] Preferably, the bridge deck, UHPC junction slab, and reinforced pavement layer are all provided with steel mesh, and the steel mesh in the bridge deck, UHPC junction slab, and reinforced pavement layer are connected into an integrated structure, thereby avoiding the construction difficulties caused by inconsistent reinforcement between the bridge deck, UHPC junction slab, and reinforced pavement layer, and reducing the construction difficulty.

[0008] Preferably, the upper side of the reinforced pavement layer is provided with multiple saw cuts evenly distributed along the length of the reinforced pavement layer, and the saw cuts are set along the width of the reinforced pavement layer. Asphalt sealant is injected into the saw cuts to ensure that the reinforced pavement layer can effectively absorb the expansion and contraction displacement of the main beam caused by temperature rise and fall.

[0009] Preferably, a positioning groove is provided between the upper side of the abutment and the near-ground side. A first elastic sliding layer is provided at the bottom of the positioning groove. One end of the sunken approach slab extends into the positioning groove and rests on the first elastic sliding layer, allowing the sunken approach slab to move slightly relative to the abutment, thus better absorbing the displacement of the reinforced pavement layer caused by the temperature deformation of the main beam. Preferably, the first elastic sliding layer is 5-15mm thick asphalt felt.

[0010] Preferably, the bridge deck is shorter than the main beam, exposing the upper side of the end of the main beam. One end of the UHPC junction plate extends to the upper side of the end of the main beam, and the other end extends to the upper side of the abutment. A second elastic sliding layer is provided between the UHPC junction plate and the main beam, and between the UHPC junction plate and the abutment. This allows the UHPC junction plate to generate relative displacement and slight rotation with respect to the abutment, better transferring the temperature deformation of the main beam to the reinforced pavement layer. Preferably, the second elastic sliding layer is a 5mm thick waterproof self-adhesive asphalt felt.

[0011] Preferably, the material of the UHPC junction plate is ultra-high performance concrete, and the slip layer includes an emulsified asphalt layer and a geotextile. The thickness of the emulsified asphalt layer is 5-10 mm, and the geotextile is laid on the upper side of the emulsified asphalt layer with the smooth side facing down and the rough side facing up.

[0012] Preferably, the ground beam is supported by precast concrete piles at the bottom, the soil layer below the sunken slab is replaced with EPS lightweight concrete layer, both the sunken slab and the ground beam are equipped with steel reinforcement structure, the steel reinforcement structure in the sunken slab is connected to the steel reinforcement structure in the ground beam, and the sunken slab and the ground beam are integrally cast.

[0013] This invention also provides a construction method for a seamless bridge structure with an extended deck suitable for soft soil areas, comprising the following steps:

[0014] S1. Construction of the bridge span structure: The piers and abutments are constructed at the predetermined locations, and the main beams are erected between the abutments and the piers on the near side of the bridge. Then, the main bridge deck is constructed: Waterproof self-adhesive asphalt felt is installed on the upper side of the ends of the main beams and on the upper side of the abutments as a second elastic sliding layer. Then, the formwork for the bridge deck is set on the main beams. Then, steel mesh is laid at the positions of the bridge deck and the UHPC junction plate. Concrete is then poured into the formwork of the bridge deck. When the concrete of the bridge deck has solidified to the required strength, the formwork for the UHPC junction plate is set between the abutments and the main beams and / or between adjacent main beams. Then, ultra-high performance concrete is poured into the formwork of the UHPC junction plate until the ultra-high performance concrete of the UHPC junction plate has solidified to the required strength. The main bridge deck construction is then completed.

[0015] S2. Construction of the structure behind the abutment: The soil layer below the location where the sunken approach slab needs to be installed will be replaced with an EPS lightweight concrete layer using the replacement method. Replacement will be carried out in multiple layers, with each layer's thickness controlled to meet requirements. Each layer must be filled and compacted separately, and leveling and grading will be performed after each layer is completed. Precast concrete piles will be fabricated, and after measuring the ground pile positions, piles will be laid and driven until they reach the required positions. Then, asphalt felt will be installed on the near-ground side of the abutment as the first elastic sliding layer. Subsequently, the sunken approach slab and ground beam will be constructed. The specific construction process for the sunken approach slab and ground beam is as follows: Measurement... The process includes setting out, formwork installation, installation of the steel reinforcement structure of the ground beam and the sunken approach slab, binding and connecting the steel reinforcement structures of the ground beam and the sunken approach slab, followed by pouring. The pouring process is as follows: concrete mixing and transportation, concrete pouring and initial leveling, concrete vibration and leveling, concrete surface treatment, and concrete curing. After pouring, one end of the sunken approach slab is placed on the first elastic sliding layer on the near-ground side of the abutment, and the other end is integrated with the ground beam. The upper part of the ground beam has a 12cm steel reinforcement structure reserved for subsequent connection with the reinforced pavement layer, and the lower part of the ground beam is connected to the precast concrete piles.

[0016] S3. Construction of the slip layer: Construct a template with a height of 3cm and the same length and width as the sunken slab. Pour emulsified asphalt into the template to form an emulsified asphalt layer and wait for the emulsified asphalt layer to solidify. After the emulsified asphalt layer solidifies, perform surface treatment and curing. After the emulsified asphalt layer is fully cured, lay the geotextile on the emulsified asphalt layer with the smooth side down and the rough side up.

[0017] S4. Construction of reinforced pavement layer: Set up the formwork for the reinforced pavement layer above the geotextile, then install the steel mesh inside the formwork and treat it with rust prevention. One end of the steel mesh inside the formwork is connected to the steel structure reserved above the ground beam, and the other end is connected to the steel mesh of the UHPC junction plate. Then pour concrete into the formwork of the reinforced pavement layer. After the concrete of the reinforced pavement layer has solidified to the required strength, open several saw cuts with a depth of 3cm on the upper surface of the reinforced pavement layer. The saw cuts are evenly distributed along the length of the reinforced pavement layer and set along the width of the reinforced pavement layer. Asphalt grout is injected into the saw cuts.

[0018] S5. Construction of asphalt concrete surface layer: Asphalt concrete is laid on the upper side of the bridge deck, UHPC junction slab, and reinforced pavement layer to complete the construction.

[0019] Compared with existing technologies, the advantages of the above solution are:

[0020] 1. The novel extended deck seamless bridge structure proposed in this scheme overcomes the disadvantage that the traditional extended deck seamless bridge structure is not suitable for soft soil areas.

[0021] 2. This novel extended-deck seamless bridge structure employs a sunken approach slab to control uneven settlement of the bridge approach pavement, while a reinforced pavement layer located above the sunken approach slab absorbs the expansion and contraction deformation of the main bridge beam. These two elements complement each other, simplifying the stress distribution and reducing structural damage. In contrast, traditional seamless bridges connect a reinforced pavement layer behind a concrete approach slab. The concrete approach slab is prone to tensile cracking under the thermal expansion and contraction of the main bridge beam, while the reinforced pavement layer is susceptible to bending cracking under uneven settlement at the bridge approach, leading to structural damage.

[0022] 3. This new type of extended bridge deck seamless bridge structure adopts a sunken approach slab to support the reinforced pavement layer, which not only avoids increasing the length of the road-bridge connection section, but also reduces the thickness of the reinforced pavement, thereby reducing material usage and lowering construction costs and difficulties.

[0023] 4. This novel extended bridge deck seamless bridge structure completes the connection between the bridge deck and the reinforced pavement layer through the UHPC junction plate. The bridge deck, UHPC junction plate and steel mesh in the reinforced pavement layer are connected into an integrated structure, which ensures good flatness and avoids the construction difficulties caused by inconsistent reinforcement of the bridge deck, sunken approach slab and reinforced pavement layer, thus reducing the construction difficulty.

[0024] 5. This novel extended bridge deck seamless bridge structure effectively controls the overall settlement of the road-bridge connection section and improves the durability and stability of the structure by replacing the sunken approach slab with an EPS lightweight concrete layer and setting ground beams and precast concrete piles in the fixed area of ​​the reinforced pavement layer. Attached Figure Description

[0025] Figure 1 A schematic diagram of an extended bridge deck seamless bridge structure suitable for soft soil areas;

[0026] Figure 2 A schematic diagram of an abutment and reinforced pavement layer for a seamless extended bridge deck structure suitable for soft soil areas.

[0027] Figure 3 A right-side schematic diagram of a seamless extended bridge deck structure suitable for soft soil regions;

[0028] Figure 4 A top view schematic diagram of a UHPC junction slab and reinforced pavement layer for a seamless extended bridge deck structure suitable for soft soil areas;

[0029] Figure 5 A schematic diagram of a sunken approach slab and reinforced pavement layer for a seamless extended bridge structure suitable for soft soil areas;

[0030] Figure 6 A top view schematic diagram of a steel mesh frame for a seamless extended bridge deck structure suitable for soft soil areas;

[0031] Figure 7 A diagram showing the saw cut locations for a seamless extended bridge deck structure suitable for soft soil regions.

[0032] Figure 8 Detailed saw cut of a seamless extended bridge deck structure suitable for soft soil regions;

[0033] Figure 9 A top view schematic diagram of a steel mesh frame and ground beam for a seamless extended bridge structure suitable for soft soil areas;

[0034] Figure 10 A schematic diagram of a steel mesh frame and ground beam for a seamless extended bridge structure suitable for soft soil areas;

[0035] Figure 11 A construction flowchart for a seamless extended bridge deck structure suitable for soft soil areas;

[0036] Figure 12 This is a construction schematic diagram of a seamless bridge structure with an extended deck suitable for soft soil areas.

[0037] Explanation of reference numerals in the attached figures.

[0038] 1. Abutment; 11. Positioning groove; 2. Main beam; 21. Bridge deck; 3. Sunken approach slab; 31. Slip layer; 32. EPS lightweight concrete layer; 33. Reinforced concrete structure; 4. UHPC junction slab; 5. Reinforced pavement layer; 51. Expansion / contraction buffer zone; 52. Fixed zone; 53. Ground beam; 54. Saw joint; 55. Precast concrete pile; 6. Reinforcing steel mesh; 61. Longitudinal reinforcement; 62. Transverse reinforcement; 7. Pier; 71. Sliding bearing; 8. First elastic slip layer; 9. Second elastic slip layer; 10. Asphalt concrete surface layer. Detailed Implementation

[0039] To make the above-mentioned objectives, features, and advantages of the present invention more apparent and understandable, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should also be noted that all directional indications (such as up, down, left, right, front, back, inside, outside) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of the components in a specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0040] Example 1

[0041] Please see Figures 1-12 Embodiment 1 of the present invention provides a seamless extended bridge structure suitable for soft soil areas, comprising an abutment 1, a main beam 2, a sunken approach slab 3, a UHPC junction slab 4, a reinforced pavement layer 5, and a ground beam 53. The main beam 2 overlaps the bridge abutment 1 on the near-bridge side, and a bridge deck 21 is provided on the main beam 2. One end of the sunken approach slab 3 overlaps the bridge abutment 1 on the near-ground side, and the other end is connected to the ground beam 53. The reinforced pavement layer 5 includes an expansion and contraction buffer zone 51 located above the sunken approach slab 3 and a connection to the ground beam. The fixed area 52 above 53 has a sliding layer 31 connected to the expansion and contraction buffer zone 51 on its upper side; the UHPC junction plate 4 is located on the abutment 1, one end of the UHPC junction plate 4 is connected to the expansion and contraction buffer zone 51 and the other end is connected to the bridge deck 21, so that the upper sides of the bridge deck 21, the UHPC junction plate 4 and the reinforced pavement layer 5 are all flush; the upper sides of the bridge deck 21, the UHPC junction plate 4 and the reinforced pavement layer 5 are all covered with an asphalt concrete surface layer 10.

[0042] The above-mentioned scheme connects the bridge deck 21, the UHPC junction plate 4, and the reinforced pavement layer 5 into an integrated structure. This ensures the smoothness of the junction between the bridge deck and the reinforced pavement layer 5, improving the driving experience. Furthermore, it allows the temperature deformation of the main beam 2 to be directly transferred to the reinforced pavement layer 5. Since the expansion and contraction buffer zone 51 of the reinforced pavement layer 5 is connected to the sunken approach slab 3 via a sliding layer 31, the expansion and contraction buffer zone 51 can generate relative displacement with the sunken approach slab 3, thereby absorbing the displacement caused by the thermal expansion and contraction of the main beam 2. Simultaneously, by placing the sunken approach slab 3 below the reinforced pavement layer 5, it provides excellent support for the reinforced pavement layer 5, not only preventing bending of the reinforced pavement layer 5 due to uneven settlement but also reducing the thickness of the reinforced pavement layer 5 and saving materials. It should also be noted that the "near-bridge side" of the abutment 1 refers to the side closest to the bridge, and the "near-ground side" refers to the side closest to the pavement.

[0043] In this embodiment, a steel mesh 6 is provided in the bridge deck 21, the UHPC junction plate 4, and the reinforced pavement layer 5, and the steel mesh 6 in the bridge deck 21, the UHPC junction plate 4, and the reinforced pavement layer 5 are connected into an integrated structure. Specifically, the steel mesh 6 is composed of multiple longitudinal steel bars 61 and multiple transverse steel bars 62 connected in a grid-like structure. The longitudinal steel bars 61 in the bridge deck 21, the UHPC junction plate 4, and the reinforced pavement layer 5 are shared and integrated, that is, the longitudinal steel bars 61 of the steel mesh 6 extend simultaneously above the main beam 2, above the abutment 1, above the sunken approach slab 3, and above the ground beam 53. The longitudinal steel bars 61 and the transverse steel bars 62 are fixed together by welding. When concrete is poured to the position where the steel mesh 6 is located on the main beam 2, the bridge deck 21 is formed. When concrete is poured to the position where the steel mesh 6 is located above the sunken approach slab 3 and the ground beam 53, the reinforced pavement layer 5 is formed. When ultra-high performance concrete is poured to the position where the steel mesh 6 is located between the bridge deck 21 and the reinforced pavement layer 5, the UHPC junction slab 4 is formed. Using this structure avoids the construction difficulties caused by inconsistent reinforcement between the bridge deck 21, the UHPC junction slab 4, and the reinforced pavement layer 5, effectively reducing the construction difficulty.

[0044] In this embodiment, the UHPC junction plate 4 is made of ultra-high performance concrete, thus possessing better tensile and compressive strength. The slip layer 31 includes an emulsified asphalt layer and a geotextile. The thickness of the emulsified asphalt layer is 5-10 mm, and the geotextile is laid on the upper side of the emulsified asphalt layer with the smooth side facing down and the rough side facing up.

[0045] Furthermore, the upper surface of the reinforced pavement layer 5 is provided with multiple equally spaced saw cuts 54 along the length of the reinforced pavement layer 5, and the saw cuts 54 are set along the width of the reinforced pavement layer 5, thereby ensuring that the reinforced pavement layer 5 can effectively absorb the displacement effect of the main beam 2 caused by temperature deformation. In addition, the fixed area 52 of the reinforced pavement layer 5 is fixed relative to the ground by connecting to the ground beam 53, and the soil layer below the sunken approach slab 3 is replaced with an EPS lightweight concrete layer 32 to reduce the weight of the soil layer and reduce foundation settlement.

[0046] In this embodiment, a support groove is provided between the upper side of the abutment 1 and the side near the bridge. A sliding support 71 is provided at the bottom of the support groove. The lower side of the main beam 2 rests on the sliding support 71 in the support groove, so that the end of the main beam 2 can be stably installed in the support groove. The sliding support 71 allows the main beam 2 to better transmit its temperature deformation. The material of the sliding support 71 is preferably polytetrafluoroethylene, which has high strength and good wear resistance; of course, other materials with similar properties can also be used.

[0047] As an extension of the above embodiments, the above scheme also includes a pier 7 for supporting the main beam 2. The upper left and right sides of the pier 7 are respectively provided with sliding supports 71 for the main beam 2 to rest on. The ends of adjacent main beams 2 can be connected to the sliding supports 71 on the left and right sides of the pier 7, so that the bridge length can be changed as needed by adding main beams 2 and piers 7.

[0048] In this embodiment, a positioning groove 11 is provided between the upper side and the near-ground side of the abutment 1. A first elastic sliding layer 8 is provided at the bottom of the positioning groove 11. One end of the sunken approach slab 3 extends into the positioning groove 11 and is placed on the first elastic sliding layer 8, thereby allowing the sunken approach slab 3 to move slightly relative to the abutment 1, better absorbing the displacement of the reinforced pavement layer 5 caused by the temperature deformation of the main beam 2. The first elastic sliding layer 8 is preferably an asphalt felt with a thickness of 5-15mm.

[0049] In this embodiment, the bridge deck 21 is shorter than the main beam 2, so that the upper side of the end of the main beam 2 is exposed. One end of the UHPC junction plate 4 extends to the upper side of the end of the main beam 2 and the other end extends to the upper side of the abutment 1. A second elastic sliding layer 9 is provided between the UHPC junction plate 4 and the main beam 2, and between the UHPC junction plate 4 and the abutment 1, so that the UHPC junction plate 4 can generate relative displacement and slight rotation with respect to the abutment 1, thereby better transmitting the temperature deformation of the main beam 2 to the reinforced pavement layer 5. The second elastic sliding layer 9 is preferably a 5mm thick waterproof self-adhesive asphalt felt.

[0050] The ground beam 53 is supported by the precast concrete piles 55 below. Both the sunken slab 3 and the ground beam 53 are equipped with steel reinforcement structures 33. The steel reinforcement structures 33 in the sunken slab 3 and the steel reinforcement structures 33 in the ground beam 53 are tied together and connected to each other. The sunken slab 3 and the ground beam 53 are cast as a whole.

[0051] Example 2

[0052] Embodiment 2 of the present invention provides a construction method for a seamless bridge structure with an extended deck suitable for soft soil areas, comprising the following steps:

[0053] S1. Construction of the bridge span structure: Piers 7 and abutments 1 are constructed at the predetermined locations, and main beams 2 are erected between the bridge abutment 1 and pier 7 on the bridge side near the bridge. Then, the main bridge deck is constructed: 5mm thick waterproof membrane self-adhesive asphalt felt is installed on the upper side of the end of the main beam 2 and the upper side of the abutment 1 as a second elastic sliding layer 9. Then, the template of the bridge deck 21 is set on the main beam 2. Then, steel mesh 6 is laid at the position of the bridge deck 21 and the position of the UHPC junction plate 4. Then, concrete is poured into the template of the bridge deck 21. When the concrete of the bridge deck 21 has solidified to the required strength, the template of the UHPC junction plate 4 is set between the abutment 1 and the main beam 2 and / or between adjacent main beams 2. Then, ultra-high performance concrete is poured into the template of the UHPC junction plate 4 until the ultra-high performance concrete of the UHPC junction plate 4 has solidified to the required strength. The main bridge deck construction is completed.

[0054] S2. Construction of the structure behind abutment 1: The soil layer below the location where the sunken approach slab 3 needs to be installed will be replaced with an EPS lightweight concrete layer 32 using the replacement method. The replacement will be carried out in multiple layers, and the thickness of each layer will be controlled to meet the requirements. Each layer needs to be filled and compacted separately. After each layer of backfilling is completed, leveling and grading will be carried out. Concrete precast piles 55 will be fabricated, and the pile positions on the ground will be measured before the piles are laid and driven until the concrete precast piles 55 reach the required positions. Then, asphalt felt will be set as the first elastic sliding layer 8 on the near-ground side of abutment 1. Subsequently, the sunken approach slab 3 and the ground beam 53 will be fabricated. The specific construction process of the sunken approach slab 3 and the ground beam 53 is as follows: measurement and layout, formwork. The installation of the steel reinforcement structure 33 of the ground beam 53 and the steel reinforcement structure 33 of the sunken approach slab 3 is carried out. The steel reinforcement structures 33 of the ground beam 53 and the sunken approach slab 3 are tied and connected, and then the concrete is poured. The pouring process is as follows: concrete mixing and transportation, concrete pouring and initial leveling, concrete vibration and leveling, concrete surface treatment, and concrete curing. After the pouring is completed, one end of the sunken approach slab 3 is placed on the first elastic sliding layer 8 on the near-ground side of the abutment 1, and the other end is integrated with the ground beam 53. The upper part of the ground beam 53 has a 12cm steel reinforcement structure 33 reserved for subsequent connection with the reinforced pavement layer 5, and the lower part of the ground beam 53 is connected to the precast concrete pile 55.

[0055] S3. Construction of slip layer 31: Construct a template with a height of 3cm and the same length and width as the sunken slab 3. Pour emulsified asphalt into the template to form an emulsified asphalt layer and wait for the emulsified asphalt layer to solidify. After the emulsified asphalt layer solidifies, perform surface treatment and curing. After the emulsified asphalt layer is fully cured, lay the geotextile on the emulsified asphalt layer with the smooth side down and the rough side up.

[0056] S4. Construction of reinforced pavement layer 5: Set up the formwork for reinforced pavement layer 5 above the geotextile. Then install the steel mesh 6 inside the formwork for reinforced pavement layer 5 and treat it with rust prevention. One end of the steel mesh 6 inside the formwork for reinforced pavement layer 5 is connected to the steel structure 33 reserved above the ground beam 53, and the other end is connected to the steel mesh 6 of the UHPC junction plate 4. Then pour concrete into the formwork for reinforced pavement layer 5. After the concrete of reinforced pavement layer 5 has solidified to the required strength, open several saw cuts 54 with a depth of 3cm on the upper surface of reinforced pavement layer 5. The saw cuts 54 are evenly distributed along the length direction of reinforced pavement layer 5 and set along the width direction of reinforced pavement layer 5. Asphalt grout is injected into the saw cuts.

[0057] S5. Construction of Asphalt Concrete Surface Layer 10: Asphalt concrete is laid on the upper side of bridge deck 21, UHPC junction slab 4, and reinforced pavement layer 5 to complete the construction.

[0058] More specifically, in step S2, measuring the ground pile position refers to using a theodolite to lay out the pile driving points, and using a level to observe and control the pile driving positioning and verticality during the pile driving process. The precast concrete pile 55 is preferably a square pile. During lifting and transportation, the lifting points and support points designed are strictly followed. When lifting the precast concrete pile 55, the crane uses a single-point lifting method. The pile position is checked twice using the rectangular coordinate method according to the set control pile. After it is correct, the square pile is driven in. The center point of the pile tip is aligned with the reinforcement point of the pile position to start driving the pile. When the pile tip is driven in 500mm, two theodolites are used at a 90-degree angle to adjust the verticality of the first pile. During observation, the verticality deviation between the upper and lower ends should be <0.5%. Then the pile driving begins, and observation is carried out while driving. If the deviation exceeds the tolerance, it is adjusted in time.

[0059] Furthermore, it should be noted that the steel mesh 6 in steps S1 and S4 is made of longitudinal steel bars 61 with a diameter of 16cm and transverse steel bars 62 with a diameter of 12cm laid in a mesh pattern, and the steel mesh 6 needs to be coated with anti-rust liquid during laying; the depth of the saw joint 54 of the reinforced pavement layer 5 in step S4 is 3cm; the templates of the bridge deck 21, the UHPC junction plate 4, and the reinforced pavement layer 5 form a whole of equal height after the corresponding concrete is poured, thereby ensuring the flatness of the final asphalt concrete surface layer 10.

[0060] While the disclosure is as stated above, its scope of protection is not limited thereto. Those skilled in the art will be able to make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the scope of protection of the invention.

Claims

1. A construction method for a seamless extended bridge deck structure suitable for soft soil areas, the seamless extended bridge deck structure suitable for soft soil areas includes an abutment (1), a main beam (2), a sunken approach slab (3), a UHPC junction slab (4), a reinforced pavement layer (5), and a ground beam (53). The main beam (2) overlaps the bridge abutment (1) on the near-bridge side, and a bridge deck (21) is provided on the main beam (2). One end of the sunken approach slab (3) overlaps the bridge abutment (1) on the near-ground side, and the other end is connected to the ground beam (53). The reinforced pavement layer (5) includes an expansion and contraction buffer zone (51) located above the sunken approach slab (3). The upper side of the sunken approach slab (3) is provided with a sliding layer (31) connected to the expansion and contraction buffer zone (51) and a fixed area (52) connected to the ground beam (53); the UHPC junction plate (4) is provided on the abutment (1), one end of the UHPC junction plate (4) is connected to the expansion and contraction buffer zone (51) and the other end is connected to the bridge deck (21), so that the upper sides of the bridge deck (21), the UHPC junction plate (4) and the reinforced pavement layer (5) are all flush; the upper sides of the bridge deck (21), the UHPC junction plate (4) and the reinforced pavement layer (5) are all covered with an asphalt concrete surface layer (10); A positioning groove (11) is provided between the upper side of the bridge abutment (1) and the near-ground side. A first elastic sliding layer (8) is provided at the bottom of the positioning groove (11). One end of the sunken approach slab (3) extends into the positioning groove (11) and is placed on the first elastic sliding layer (8). The bridge deck (21) is shorter than the main beam (2) so that the upper side of the end of the main beam (2) is exposed. One end of the UHPC junction plate (4) extends to the upper side of the end of the main beam (2) and the other end extends to the upper side of the abutment (1). A second elastic sliding layer (9) is provided between the UHPC junction plate (4) and the main beam (2) and between the UHPC junction plate (4) and the abutment (1). The ground beam (53) is supported by precast concrete piles (55) at the bottom. The soil layer below the sunken slab (3) is replaced with EPS lightweight concrete layer (32). The sunken slab (3) and the ground beam (53) are both equipped with steel reinforcement structure (33), and the steel reinforcement structure (33) in the sunken slab (3) is connected to the steel reinforcement structure (33) in the ground beam (53). Its features are, Includes the following steps: S1. Construction of the bridge span structure: The piers (7) and abutments (1) are constructed at the preset positions, and the main beam (2) is erected between the bridge abutment (1) and the pier (7); then the main body of the bridge deck is constructed: Waterproof self-adhesive asphalt felt is installed on the upper side of the end of the main beam (2) and the upper side of the abutment (1) as a second elastic sliding layer (9), and then the template of the bridge deck (21) is set on the main beam (2), and then the UHPC junction plate ( 4) Lay the steel mesh frame (6) at the location, and then pour concrete into the template of the bridge deck (21). When the concrete of the bridge deck (21) reaches the required strength, set the template of the UHPC junction plate (4) between the abutment (1) and the main beam (2) and / or between the adjacent main beam (2). Then pour ultra-high performance concrete into the template of the UHPC junction plate (4) until the ultra-high performance concrete of the UHPC junction plate (4) reaches the required strength. The main construction of the bridge deck is completed. S2. Construction of the structure behind the abutment: The soil layer below the location where the sunken approach slab (3) needs to be set will be replaced with EPS lightweight concrete layer (32) using the replacement method. The replacement will be carried out in multiple layers and the thickness of each layer will be controlled to meet the requirements. Each layer needs to be filled and compacted separately. After each layer is backfilled, leveling and grading will be carried out. Concrete precast piles (55) will be made, and the ground pile positions will be measured and piles will be laid and driven until the concrete precast piles (55) reach the required position. Then, tar paper will be set as the first elastic sliding layer (8) on the near-ground side of the abutment (1). Subsequently, the sunken approach slab (3) and ground beam (53) will be made. The specific construction process of the sunken approach slab (3) and ground beam (53) is as follows: measurement and layout, formwork installation, ground beam (53) The steel reinforcement structure (33) of the bridge abutment (1) is installed and the steel reinforcement structure (33) of the sunken approach slab (3) is installed. The steel reinforcement structure (33) of the ground beam (53) and the sunken approach slab (3) is tied and connected. Then the concrete is poured. The pouring process is as follows: concrete mixing and transportation, concrete pouring and initial leveling, concrete vibration and leveling, concrete surface treatment, and concrete curing. After the pouring is completed, one end of the sunken approach slab (3) is placed on the first elastic sliding layer (8) on the near-ground side of the bridge abutment (1), and the other end is connected to the ground beam (53) and forms a whole. The upper part of the ground beam (53) is reserved with a 12cm steel reinforcement structure (33) for subsequent connection to the reinforced pavement layer (5). The lower part of the ground beam (53) is connected to the precast concrete pile (55). S3. Construction of the slip layer (31): Build a template with a height of 3cm and the same length and width as the sunken slab (3), pour emulsified asphalt into the template to form an emulsified asphalt layer, and wait for the emulsified asphalt layer to solidify. After the emulsified asphalt layer solidifies, perform surface treatment and curing. After the emulsified asphalt layer is fully cured, lay the geotextile on the emulsified asphalt layer with the smooth side down and the rough side up. S4. Construction of reinforced pavement layer (5): Set up the template of reinforced pavement layer (5) above the geotextile, then install the steel mesh frame (6) in the template of reinforced pavement layer (5) and perform anti-rust treatment on it. One end of the steel mesh frame (6) in the template of reinforced pavement layer (5) is connected to the steel structure (33) reserved on the upper part of the ground beam (53), and the other end is connected to the steel mesh frame (6) of the UHPC junction plate (4). Then pour concrete into the template of reinforced pavement layer (5). After the concrete of reinforced pavement layer (5) has solidified to the required strength, open a number of saw cuts (54) with a depth of 3cm on the upper surface of reinforced pavement layer (5). The saw cuts (54) are evenly distributed along the length direction of reinforced pavement layer (5) and set along the width direction of reinforced pavement layer (5). The inside of the saw cuts (54) is filled with asphalt grout. S5. Construction of the asphalt concrete surface layer (10): Asphalt concrete is laid on the upper side of the bridge deck (21), UHPC junction plate (4), and reinforced pavement layer (5) to complete the construction.

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