Bridge large cantilevered sidewalk overhang structure

Abstract

This utility model relates to the field of bridge engineering technology, and in particular to a cantilevered pedestrian walkway structure for bridges. The cantilevered pedestrian walkway structure provided in this utility model embodiment includes: multiple support systems spaced apart along the extension direction of the bridge; each support system includes: a support mechanism, one end of which is connected to the bridge, and the other end extending outwards to form a support portion; a crossbeam, which is disposed on the support portion of the support mechanism, with one end of the crossbeam adjacent to the bridge and connected to the bridge; and a paving system laid on the multiple crossbeams to form a cantilevered pedestrian walkway with a cantilever length of 1.0 meter or more. The cantilevered pedestrian walkway structure provided in this utility model embodiment can significantly widen the cantilever of existing bridge pedestrian walkways, breaking through the traditional 50-centimeter cantilever length limitation, and providing an effective technical solution for the renovation of existing bridge pedestrian walkways.

Description

Technical Field

[0001] This utility model relates to the field of bridge engineering technology, and in particular to a cantilevered pedestrian walkway structure for bridges with large cantilever arms. Background Technology

[0002] With the acceleration of urbanization and the increase in population density, urban traffic pressure is increasing, placing higher demands on the capacity of existing bridges. In bridge traffic organization, the width design of sidewalks, as dedicated passageways for pedestrians, directly affects the safety and comfort of pedestrians.

[0003] However, many existing bridges in my country were built in earlier times with relatively low design standards, resulting in generally insufficient sidewalk widths. Surveys show that many urban bridges built in the 1980s and 1990s have sidewalks with a clear width of less than 1.0 meter, far below current standards. Under current conditions, this insufficient sidewalk width leads to serious traffic problems: during peak hours, pedestrian congestion and low traffic efficiency occur; during emergency evacuations, evacuation routes are insufficient, posing safety hazards; and narrow sidewalks also negatively impact the overall image of the city and residents' travel experience.

[0004] To address the issue of insufficient pedestrian walkway width on existing bridges, the engineering community has proposed various technical solutions. Reconstructing the bridge itself is the most thorough solution, but it involves enormous investment, a long construction period, and severe disruption to urban traffic, making it economically and socially unacceptable. Therefore, widening the pedestrian walkways on existing bridges has become a more realistic and economical option.

[0005] Currently, the main technical method for widening existing bridge sidewalks is to increase the cantilever length of the sidewalk cantilever beam. The traditional method involves adding cantilever sections to the existing cantilever beam, thus expanding the sidewalk width by increasing the cantilever length. However, this method has significant technical limitations:

[0006] First, the structural form of traditional cantilever beams limits their cantilever capacity. When a conventional reinforced concrete cantilever beam bears a cantilever load, the bending moment at the root increases with the square of the cantilever length. When the cantilever length exceeds a certain limit, the stress on the root section will exceed the material's bearing capacity. Practice shows that traditional cantilever beam widening methods can only increase the cantilever length of sidewalk cantilever beams to a maximum of 50 centimeters, which is far from sufficient to meet the actual needs of widening sidewalks.

[0007] Secondly, widening traditional cantilever beams requires significant modifications to the existing beams, including increasing the beam cross-section and strengthening the reinforcement. This process is highly complex, has a significant impact on the original bridge structure, and can easily lead to structural safety issues. Furthermore, the on-site pouring of concrete cantilever beams requires formwork, pouring, and curing processes, resulting in a long construction period and severe disruption to traffic both above and below the bridge. Utility Model Content

[0008] This utility model provides a bridge cantilever pedestrian walkway cantilever structure, which can significantly widen the cantilever of existing bridge pedestrian walkways, breaking through the traditional 50 cm cantilever length limitation, and providing an effective technical solution for the renovation of existing bridge pedestrian walkways.

[0009] This utility model embodiment provides a cantilevered pedestrian walkway structure for a bridge, comprising: multiple support systems spaced apart along the extension direction of the bridge; each support system includes: a support mechanism, one end of which is connected to the bridge and the other end extending outward from the bridge to form a support portion; a crossbeam disposed on the support portion of the support mechanism, with one end of the crossbeam adjacent to the bridge and connected to the bridge; and a paving system laid on the multiple crossbeams to form a cantilevered pedestrian walkway with a cantilever length of 1.0 meter or more.

[0010] In one possible implementation, the support structure includes: a support steel plate, one end of which is connected to the bridge and the other end extends outward to form a support section; and an anchoring stiffening steel plate, which is connected to the support steel plate and connected to the superstructure of the bridge.

[0011] In one possible implementation, the anchoring stiffening steel plate includes: a first plate body disposed at the end of the supporting steel plate and connected to the web of the superstructure via a first fastener; and a second plate body connected to the first plate body, disposed above the supporting steel plate and connected to the wing plate of the superstructure via a second fastener.

[0012] In one possible implementation, the first and second fasteners are anchored using rebar anchoring technology, with an anchoring depth of 12 centimeters or more.

[0013] In one possible implementation, the supporting steel plate and the anchoring stiffening steel plate are connected by penetration welding.

[0014] In one possible implementation, the crossbeam includes: an I-beam mounted on a support; and a cantilever stiffening plate mounted on the end of the I-beam adjacent to the bridge, the cantilever stiffening plate being connected to the bridge's guardrail foundation via a third fastener.

[0015] In one possible implementation, the I-beam and the cantilever stiffening plate are connected by full penetration welding.

[0016] In one possible implementation, the distance between two adjacent support systems is within 1.5 meters.

[0017] In one possible implementation, the paving system includes: multiple channel steels laid on and fixedly connected to the crossbeams, the channel steels being arranged along the extension direction of the bridge; and paving slabs laid on the multiple channel steels.

[0018] In one possible implementation, the paving plate is a patterned steel plate with a thickness of 5 mm or more.

[0019] The cantilevered pedestrian walkway structure for bridges provided by this utility model provides a stable anchoring foundation by reliably connecting one end of the support mechanism to the bridge, while the other end extends outward from the bridge to form a support section. This provides a support point for the crossbeams away from the main bridge structure, allowing the cantilever structure to extend outward over a greater distance. The crossbeams are set on the support section, with one end adjacent to the bridge connected to it, forming a double-constrained force system. This double constraint significantly improves the crossbeams' anti-overturning and load-bearing capacity, enabling them to withstand the large bending and overturning moments generated by the large cantilever. The pavement system is laid on multiple crossbeams to form a continuous pedestrian walkway. Through multi-point support, the pedestrian load is evenly distributed and transferred to each support system, avoiding concentrated stress at a single point, and ultimately safely transferring the load to the original bridge structure.

[0020] The core advantage of this three-stage force transmission structure lies in its transformation of the traditional cantilever structure's stress distribution mode. Traditional cantilever beams employ a root-fixed cantilever beam stress distribution mode, where the load at the cantilever end is entirely borne by the root. The bending moment at the root increases with the square of the cantilever length, severely limiting the cantilever's capacity. In contrast, the support mechanism of this invention provides intermediate support points to the crossbeam by extending outwards. The crossbeam's connection to the bridge end near the bridge creates additional constraints, transforming the crossbeam from a simple cantilever beam into a complex stress-bearing structure with intermediate support and end constraints. This significantly reduces the bending moment and deformation at the cantilever end, enabling it to withstand greater cantilever lengths. The spaced arrangement of multiple support systems further optimizes the load transfer path, resulting in relatively smaller loads on each support system and improving the overall structural safety and reliability. This allows for a substantial widening of the cantilever of existing bridge pedestrian walkways, breaking through the traditional 50cm cantilever length limitation and providing an effective technical solution for the renovation of existing bridge pedestrian walkways. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of a cantilevered pedestrian walkway structure for a bridge provided by this utility model.

[0023] Figure 2 This is a top view structural diagram of a bridge and support system provided by this utility model.

[0024] Figure 3 This is a three-dimensional structural diagram of an I-beam and paving system provided by this utility model.

[0025] Figure 4 This is a three-dimensional structural diagram of a bridge and support system provided by this utility model.

[0026] Figure 5 This is a schematic diagram of a planar structure of a supporting steel plate provided by this utility model.

[0027] Figure 6 This is a structural schematic diagram of an anchoring and stiffening steel plate provided by this utility model.

[0028] Figure 7 This is a schematic diagram of the structure of a second plate and a supporting steel plate provided by this utility model.

[0029] Figure 8 This is a schematic diagram of the structure of a first plate and a supporting steel plate provided by this utility model.

[0030] Figure 9 This is a structural schematic diagram of an I-beam and a cantilever stiffening steel plate provided by this utility model.

[0031] Figure label:

[0032] 1. Support system; 11. Support mechanism; 111. Supporting steel plate; 112. Anchoring stiffening steel plate; 1121. First plate; 1122. Second plate; 113. First fastener; 114. Second fastener; 12. Crossbeam; 121. I-beam; 122. Cantilever stiffening steel plate; 123. Third fastener;

[0033] 2. Paving system; 21. Channel steel; 22. Paving slab;

[0034] 3. Web plate; 4. Wing plate; 5. Guardrail foundation; 6. Pedestrian guardrail; 7. Bridge guardrail. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0036] The following is combined with Figure 1-9 This utility model provides a bridge cantilever pedestrian walkway structure, comprising multiple support systems 1 and pavement systems 2, wherein:

[0037] Multiple support systems 1 are spaced apart along the extension direction of the bridge. Each support system 1 includes: a support mechanism 11, one end of which is connected to the bridge and the other end extends outward from the bridge to form a support part; and a crossbeam 12, which is disposed on the support part of the support mechanism 11 and is connected to the bridge at one end adjacent to the bridge.

[0038] Paving system 2 is laid on multiple crossbeams 12 to form a cantilevered pedestrian pavement with a cantilever length of more than 1.0 meter.

[0039] In this invention, multiple support systems 1 are arranged at intervals along the extension direction of the bridge. Each support system 1 includes a three-level force transmission structure consisting of a support mechanism 11, a crossbeam 12, and a pavement system 2. This achieves a large cantilever pedestrian walkway structure with a cantilever length of over 1.0 meter, effectively solving the technical problem of insufficient clear width of existing bridge pedestrian walkways. One end of the support mechanism 11 is connected to the bridge to provide a reliable anchoring foundation, while the other end extends outward from the bridge to form a support section, providing a stable support platform for the crossbeam 12. The crossbeam 12 is set on the support section and connected to the bridge, forming a double constraint system to ensure the overall stability of the cantilever structure. The pavement system 2 is laid on multiple crossbeams 12, evenly distributing and transferring pedestrian loads to each support system 1, and ultimately to the original bridge structure.

[0040] Specifically, the spaced arrangement of multiple support systems 1 disperses the load of the cantilevered sidewalk through multiple points, avoiding stress concentration caused by concentrated force at a single point. One end of the support structure 11 is anchored to the bridge, fully utilizing the original bridge structure's load-bearing capacity, while the other end extends outward from the bridge to form a support section, providing necessary support points for the cantilever structure. The crossbeam 12, as the main load-bearing component, connects to the bridge at its adjacent end, forming a dual constraint between the support structure 11 and the bridge connection, greatly improving the overturning resistance of the cantilever structure. The paving system 2 is laid on multiple crossbeams 12, forming a complete sidewalk surface through continuous paving, with a cantilever length exceeding 1.0 meter, meeting the actual needs of sidewalk widening.

[0041] In related technologies, the widening of existing bridge pedestrian walkways mainly involves increasing the cantilever length of the cantilever beams. However, this method can only increase the cantilever length of the pedestrian walkway beams by a maximum of 50 centimeters, resulting in a very limited widening effect and failing to solve the problem of insufficient clear width of the pedestrian walkway. Furthermore, traditional cantilever beam widening methods require significant modifications to the existing cantilever beams, leading to high construction difficulty, high costs, and potential impacts on the overall structural safety of the bridge.

[0042] In this embodiment of the invention, a three-level force transmission system consisting of support mechanism 11, crossbeam 12, and pavement system 2 enables a large cantilever span of over 1.0 meter, more than doubling the cantilever capacity compared to the 0.5-meter cantilever of existing technologies. The dispersed arrangement of multiple support systems 1 avoids significant alterations to the original bridge structure, requiring only anchorage connections at specific locations, facilitating construction and minimizing impact on the original structure. The three-level force transmission structure ensures a clear and defined load transfer path, with each level having a specific load-bearing function, resulting in a safe and reliable overall structure that meets the load-bearing requirements of a large cantilever span.

[0043] In some embodiments, the support mechanism 11 includes: a support steel plate 111, one end of which is connected to the bridge and the other end extends outward to form a support portion; and an anchoring stiffening steel plate 112, which is connected to the support steel plate 111 and is connected to the superstructure of the bridge.

[0044] In this invention, a support mechanism 11 is formed by combining a supporting steel plate 111 and an anchoring stiffening steel plate 112, effectively transferring the cantilever load to the original bridge structure. One end of the supporting steel plate 111 is connected to the bridge, and the other end extends outward to form a support section, providing a stable support platform for the crossbeam 12. The anchoring stiffening steel plate 112 is connected to the supporting steel plate 111 and to the bridge superstructure, forming a reliable connection between the supporting steel plate 111 and the original bridge structure, ensuring that the cantilever load can be safely transferred to the main structure of the original bridge.

[0045] Specifically, the supporting steel plate 111, as the main load-bearing component of the supporting mechanism 11, has one end connected to the bridge, allowing the cantilever load to be directly transferred to the original bridge structure. The other end extends outward to form a support section, providing an accurate support position and sufficient support area for the subsequent installation of the crossbeam 12. The anchoring stiffening steel plate 112 solves the technical problem of connecting the supporting steel plate 111 to the bridge superstructure. Through its connection with the supporting steel plate 111, the anchoring stiffening steel plate 112 can further distribute the load transferred by the supporting steel plate 111 to different parts of the bridge superstructure, avoiding local stress concentration and improving the reliability and durability of the connection.

[0046] In one specific embodiment, in the widening of the sidewalk of a prestressed concrete continuous beam bridge, the supporting steel plate 111 is made of Q345 steel, with a thickness of 12 mm and a length of 1.5 meters, capable of withstanding bending moment and shear force under the design load. The anchoring stiffening steel plate 112 is divided into two parts, which are connected to the web plate 3 and the flange plate 4 of the bridge respectively. Through reasonable size design and connection method, the load of the supporting steel plate 111 can be evenly transferred to the main load-bearing parts of the bridge. In this embodiment, the supporting mechanism 11 exhibits good load-bearing performance and stability during use, meeting the technical requirements of large cantilever cantilever.

[0047] In related technologies, traditional cantilever structure supports often use simple steel beams or concrete cantilever beams, with a single connection method to the original structure, often connecting at only one location. This can easily lead to stress concentration at the connection points, affecting the safety and durability of the structure. At the same time, simple support structures are difficult to adapt to the stress requirements of large cantilevers, and are prone to insufficient load-bearing capacity or excessive deformation under large cantilever lengths.

[0048] In this embodiment of the invention, the combined design of the supporting steel plate 111 and the anchoring stiffening steel plate 112 forms a more rational stress-bearing system. The supporting steel plate 111 mainly bears the bending moment load, while the anchoring stiffening steel plate 112 is responsible for transferring the load to the original bridge structure. The two have clear division of labor and work together effectively. The connection between the anchoring stiffening steel plate 112 and the bridge superstructure adopts a multi-point connection method, which can distribute the load and avoid the stress concentration problem of single-point connection. This combined construction method not only improves the load-bearing capacity of the supporting mechanism 11, but also enhances the reliability of the connection with the original bridge structure, providing an important technical guarantee for realizing large cantilever cantilever.

[0049] In some embodiments, the anchoring stiffening steel plate 112 includes: a first plate body 1121 disposed at the end of the supporting steel plate 111 and connected to the web plate 3 of the upper structure via a first fastener 113; and a second plate body 1122 connected to the first plate body 1121, disposed above the supporting steel plate 111 and connected to the wing plate 4 of the upper structure via a second fastener 114.

[0050] In this invention, by designing the anchoring stiffening steel plate 112 as a combined structure comprising a first plate 1121 and a second plate 1122, separate connections are achieved with the web 3 and wing 4 of the bridge superstructure, forming a reliable connection system with multi-point anchoring. The first plate 1121 is located at the end of the supporting steel plate 111 and is connected to the web 3 of the superstructure via a first fastener 113, primarily bearing the vertical and horizontal loads transmitted by the supporting steel plate 111. The second plate 1122 is connected to the first plate 1121 and is located above the supporting steel plate 111, connected to the wing 4 of the superstructure via a second fastener 114, primarily bearing the overturning moment of the supporting steel plate 111. The two plates work together to achieve reasonable load distribution and effective transmission.

[0051] Specifically, the design of the first plate 1121, located at the end of the supporting steel plate 111, allows it to directly bear various loads transmitted by the supporting steel plate 111, including vertical forces generated by pedestrian loads and horizontal forces generated by wind loads. Through the connection of the first fastener 113 to the web plate 3, the first plate 1121 can directly transfer these loads to the main load-bearing part of the bridge superstructure—the web plate 3—fully utilizing the load-bearing capacity of the main bridge structure. The connection between the second plate 1122 and the first plate 1121 forms the integral structure of the anchored stiffening steel plate 112. The second plate 1122, positioned above the supporting steel plate 111, effectively resists the overturning moment generated by the supporting steel plate 111 under cantilever loads. Through the connection of the second fastener 114 to the flange plate 4, the second plate 1122 converts the overturning moment into pressure and tension on the flange plate 4, utilizing the tensile and compressive strength of the flange plate 4 to balance the overturning moment.

[0052] In one specific embodiment, in a cantilevered widening project for a box girder bridge's pedestrian walkway, the first plate 1121, measuring 600 mm × 400 mm × 15 mm, is connected to the box girder web 3 via two M20 ordinary anchor bolts. The connection position is precisely calculated to ensure effective load transfer. The second plate 1122, measuring 800 mm × 400 mm × 15 mm, is connected to the box girder flange 4 via six M20 chemical anchor bolts. The connection position avoids prestressed steel strands, ensuring the integrity of the original structure. In this embodiment, the combined connection of the first plate 1121 and the second plate 1122 enables each support system 1 to withstand a design load of 50 kN, meeting the safety requirements for pedestrian walkway use.

[0053] In related technologies, the connection between the cantilever structure and the original bridge structure often adopts a single connection method, such as connecting only at the web 3 position or only at the flange 4 position. This single-point connection method is prone to insufficient connection strength when subjected to large loads, especially in resisting overturning moments, which is of limited effectiveness and can easily lead to connection failure or local damage to the original structure.

[0054] In this embodiment of the invention, the dual connection method, in which the first plate 1121 and the second plate 1122 are respectively connected to the web plate 3 and the flange plate 4, forms a multi-point constraint system in space, which can effectively resist loads from all directions. The connection between the first plate 1121 and the web plate 3 mainly resists vertical and horizontal loads, while the connection between the second plate 1122 and the flange plate 4 mainly resists overturning moments. The two work together to form a complete force-bearing system. This multi-point connection method not only improves the safety and reliability of the connection but also allows the load to be distributed more evenly to different parts of the original bridge structure, avoiding local stress concentration and protecting the integrity and safety of the original bridge structure.

[0055] In some embodiments, the first fastener 113 and the second fastener 114 are anchored using rebar anchoring technology, with an anchoring depth of 12 cm or more.

[0056] In this invention, the first fastener 113 and the second fastener 114 are anchored using rebar anchoring technology, with an anchoring depth of at least 12 centimeters, achieving a high-strength connection between the fasteners and the bridge superstructure. The rebar anchoring technology, through a process of drilling holes in the bridge concrete, injecting structural adhesive, and inserting rebars or bolts, enables the fasteners to form a reliable chemical and mechanical bond with the original concrete structure. The anchoring depth of at least 12 centimeters ensures that the fasteners can penetrate deep into the effective anchoring area of ​​the concrete, obtaining sufficient anchoring force to resist various loads transmitted by the cantilever structure.

[0057] Specifically, the working principle of rebar anchoring technology is to form a chemical bond between the rebar and the concrete hole wall through high-strength structural adhesive, while the ribs on the surface of the rebar form a mechanical interlock with the structural adhesive. These two actions together provide anchoring force. The first fastener 113 and the second fastener 114 are anchored using rebar anchoring technology, enabling the anchoring stiffening steel plate 112 to form a reliable connection with the bridge superstructure. The requirement of an anchoring depth of at least 12 cm ensures that the fastener can penetrate the weak layer of the concrete surface and enter the internal high-strength concrete area. Within the 12 cm anchoring depth range, the structural adhesive can bond with the surface of a sufficiently long rebar, while there is also sufficient concrete wrapping thickness to provide bond strength. Together, these factors enable the fastener to withstand the tensile, compressive, and shear forces transmitted by the cantilever structure.

[0058] In a specific embodiment, in the pedestrian walkway cantilever renovation project of a prestressed concrete T-beam bridge, both the first fastener 113 and the second fastener 114 used 20 mm diameter HRB400 steel bars, anchored with epoxy resin structural adhesive, with an anchoring depth of 15 cm. During construction, firstly, 22 mm diameter holes with a depth of 18 cm were drilled in the web 3 and flange 4 using an electric hammer. Then, the dust in the holes was cleaned, structural adhesive was injected, the steel bars were inserted, and they were kept under curing for 24 hours. After pull-out testing, the tensile strength of each anchored bar reached 80 kN, meeting the design requirements. In this embodiment, the anchored connection exhibited good load-bearing performance and durability during use, ensuring the safety and reliability of the cantilever structure.

[0059] In some embodiments, the supporting steel plate 111 and the anchoring stiffening steel plate 112 are connected by penetration welding.

[0060] In this invention, a high-strength rigid connection between the supporting steel plate 111 and the anchoring stiffening steel plate 112 is achieved by using a full penetration welding connection. Full penetration welding refers to a welding method where the weld completely penetrates the thickness of the base material. The weld metal achieves a metallurgical bond with the base material, and the connection strength reaches the same level as the base material strength. This ensures that the load transmitted by the supporting steel plate 111 can be completely and reliably transferred to the anchoring stiffening steel plate 112, preventing the connection from becoming a weak point in the entire force transmission path.

[0061] Specifically, the working principle of a full penetration weld is to completely melt the connection between the supporting steel plate 111 and the anchoring stiffening steel plate 112 using the heat of an electric arc, forming a molten pool. After cooling, the weld metal and the base material achieve metallurgical bonding, forming an integral structure. During the stress process of the cantilever structure, the pedestrian load is first transferred to the crossbeam 12, then to the supporting steel plate 111, which then transfers these loads to the anchoring stiffening steel plate 112, and finally to the original bridge structure. The full penetration weld ensures that the supporting steel plate 111 and the anchoring stiffening steel plate 112 form a continuous material at the connection point, preventing stress abrupt changes or concentrations during load transfer, thus ensuring the continuity and uniformity of force transmission. Simultaneously, the full penetration weld has excellent fatigue resistance and can withstand various dynamic loads generated during the bridge's use.

[0062] In one specific embodiment, in a cantilevered pedestrian walkway project of a reinforced concrete box girder bridge, the supporting steel plate 111 is 14 mm thick, and the anchoring stiffening steel plate 112 is 16 mm thick. The two are connected by a V-groove full penetration weld. Before welding, the connection area is precisely machined to ensure that the groove dimensions and angles meet the requirements. The welding process uses CO2 gas shielded welding, with multiple layers and multiple passes to ensure complete weld penetration. After welding, ultrasonic testing is performed, and the internal quality of the weld reaches the first-class standard, with no cracks, porosity, or other defects. In this embodiment, the full penetration weld connection exhibits good load-bearing performance under the design load, with uniform stress distribution at the connection area and no stress concentration.

[0063] In some embodiments, the crossbeam 12 includes: an I-beam 121 disposed on the support; and a cantilever stiffening plate 122 disposed at the end of the I-beam 121 adjacent to the bridge, wherein the cantilever stiffening plate 122 is connected to the bridge railing foundation 5 by a third fastener 123.

[0064] In this invention, the crossbeam 12 structure, composed of an I-beam 121 and a cantilever stiffening plate 122, effectively bears and transfers the cantilever load. The I-beam 121, as the main load-bearing component, has excellent bending resistance and a large section modulus due to its I-shaped cross-section, enabling it to effectively withstand the bending moment load generated by the cantilever structure. The cantilever stiffening plate 122 is located at the end of the I-beam 121 adjacent to the bridge end and is connected to the bridge railing foundation 5 via a third fastener 123, providing additional support points for the crossbeam 12 and forming a double constraint system, significantly improving the load-bearing capacity and overturning resistance of the crossbeam 12.

[0065] Specifically, the I-shaped cross-section design of I-beam 121 gives it a large moment of inertia and section modulus, resulting in a reasonable stress distribution and full utilization of the steel's strength when subjected to bending moment loads. I-beam 121, mounted on the support structure, transfers the pedestrian load from the pavement system 2 to the support mechanism 11 through bending deformation. The span of I-beam 121 is its cantilever length; with cantilever lengths exceeding 1.0 meter, I-beam 121 needs to withstand significant bending moments. The design of the cantilever stiffening plate 122, positioned near the bridge end of I-beam 121, provides intermediate support, transforming the original cantilever beam structure into a partially continuous beam structure. This significantly reduces the bending moment at the base of I-beam 121 and improves load-bearing efficiency. Connected to the guardrail foundation 5 via the third fastener 123, the cantilever stiffening plate 122 directly transfers part of the load to the guardrail foundation 5, and then to the main bridge structure, forming a multi-path load transfer mechanism.

[0066] In some embodiments, the I-beam 121 and the cantilever stiffening plate 122 are connected by penetration welding.

[0067] In this invention, a high-strength integral connection between the I-beam 121 and the cantilever stiffening plate 122 is achieved by using a full penetration weld. The full penetration weld allows the I-beam 121 and the cantilever stiffening plate 122 to form a metallurgical bond at the connection point. The two components can deform collaboratively under stress, sharing the load and preventing relative slippage or rotation at the connection point. This ensures the integrity and rigidity of the beam 12 structure, providing crucial support for the stable operation of the cantilever structure.

[0068] Specifically, the implementation of the full penetration weld connection enables the H-beam 121 and the cantilever stiffening plate 122 to form a rigid connection. When the beam 12 bears a cantilever load, the deformation of the H-beam 121 can be completely transferred to the cantilever stiffening plate 122, and the two deform together to form an integrated force-bearing system. Under the action of the cantilever load, the H-beam 121 mainly bears bending moment and shear force, while the cantilever stiffening plate 122 mainly bears axial force. Through the full penetration weld connection, the bending moment of the H-beam 121 can be effectively transferred to the cantilever stiffening plate 122, and the axial support force of the cantilever stiffening plate 122 can also be effectively applied to the H-beam 121. The forces of the two cooperate with each other to form an efficient force transmission mechanism. At the same time, the full penetration weld connection has good fatigue resistance and can withstand the alternating loads and vibrations of the bridge during use.

[0069] In some embodiments, the distance between two adjacent support systems 1 is within 1.5 meters.

[0070] In this invention, by controlling the spacing between two adjacent support systems 1 to within 1.5 meters, a reasonable distribution of the cantilever load among multiple support systems 1 is achieved, ensuring the uniformity of stress and the coordination of deformation of the pavement system 2. The spacing of less than 1.5 meters is based on a comprehensive consideration of the characteristics of pedestrian load distribution and the load-bearing capacity of the pavement system 2, ensuring both the effectiveness of load transfer and controlling the deflection deformation of the pavement system 2, while also taking into account the economy and operability of construction.

[0071] Specifically, the spacing of the support system 1 directly affects the stress state of the pavement system 2. When the spacing is too large, the span between the support points of the pavement system 2 increases, and the bending moment and deflection when bearing pedestrian loads will increase significantly, which may lead to insufficient load-bearing capacity or excessive deformation of the pavement system 2. A spacing of less than 1.5 meters ensures that when the pavement system 2 bears pedestrian loads at any location, the load can be transferred to the adjacent support system 1 through a shorter transmission path, avoiding the adverse stress caused by long span transmission. At the same time, the dense arrangement of the support system 1 results in a relatively small load on each support system 1, which is conducive to the standardization and modularization of the support system 1 design. With a spacing of 1.5 meters, even under the most unfavorable load arrangement, the deflection of the pavement system 2 can be controlled within the allowable range, ensuring the comfort of the sidewalk.

[0072] In some embodiments, the paving system 2 includes: multiple channel steels 21, laid on the crossbeam 12 and fixedly connected to the crossbeam 12, the channel steels 21 being arranged along the extension direction of the bridge; and paving slabs 22, laid on the multiple channel steels 21.

[0073] In this invention, a cantilevered pedestrian walkway is constructed by using multiple channel steels 21 and paving slabs 22 to form a paving system 2. The multiple channel steels 21 are laid on and fixedly connected to the crossbeams 12, arranged along the bridge's extension direction, forming the load-bearing framework of the paving system 2, effectively distributing pedestrian loads to each crossbeam 12. The paving slabs 22 are laid on the multiple channel steels 21, forming a continuous and flat pedestrian walkway, providing safe and comfortable passage conditions for pedestrians. The combination of channel steels 21 and paving slabs 22 facilitates construction, installation, and subsequent maintenance and replacement.

[0074] Specifically, the U-shaped cross-section of the channel steel 21 provides excellent bending resistance. Multiple channel steels 21 are arranged side-by-side along the bridge's extension direction, forming the main load-bearing components of the pavement system 2. The fixed connection between the channel steel 21 and the crossbeam 12 allows pedestrian loads to be transferred to the crossbeam 12 via the channel steel 21, then to the support system 1 via the crossbeam 12, and finally to the original bridge structure. The arrangement of the channel steels 21 along the bridge's extension direction ensures that the span of the channel steel 21 is equal to the spacing of the support system 1. Within a span of 1.5 meters, the channel steel 21 can effectively withstand the bending moment generated by pedestrian loads. The pavement slab 22 is laid on the channel steel 21, transforming the distributed pedestrian load into a concentrated load transferred to the channel steel 21. The continuous laying of the pavement slab 22 forms a complete pedestrian pavement, meeting the functional requirements for pedestrian passage.

[0075] In a specific embodiment, in a cantilevered pedestrian walkway project of a prestressed concrete box girder bridge, the pavement system 2 uses C-shaped channel steel 21 with specifications of C200×70×20×2.5 mm and a spacing of 300 mm, which is fixedly connected to the I-beam 121 crossbeam 12 by welding. The pavement slab 22 uses 6 mm thick checkered steel plate with dimensions of 1200 mm × 300 mm, and is connected to the channel steel 21 by bolts. Under a design load of 3.5 kN / m² for pedestrian traffic, the maximum bending moment of the channel steel 21 is 2.1 kNm, and the maximum deflection is 3 mm, both meeting the design requirements. This pavement system 2 exhibits good load-bearing capacity and durability during use, and the surface of the pavement slab 22 is smooth, providing comfortable pedestrian passage.

[0076] In related technologies, the paving of cantilevered sidewalks mostly uses cast-in-place concrete or precast concrete slabs. Cast-in-place concrete requires complex procedures such as formwork, pouring, and curing, resulting in a long construction period, and construction on existing bridges has a significant impact on traffic. Although precast concrete slabs are relatively simple to construct, they are heavy, placing high demands on the load-bearing capacity of the cantilever structure, and are difficult to maintain and replace later.

[0077] In this embodiment of the invention, the combined structure of channel steel 21 and pavement slab 22 offers advantages such as light weight, high strength, and convenient construction. Channel steel 21, as a standard steel product, boasts stable and reliable quality and is easy and quick to install on-site. The modular design of pavement slab 22 makes installation and replacement very convenient, facilitating later maintenance. Compared to concrete structures, the steel structure pavement system 2 is significantly lighter, reducing the load-bearing capacity requirements of the cantilever structure and facilitating the achievement of the large cantilever design goal. Simultaneously, the steel structure possesses excellent seismic performance, capable of adapting to bridge deformation under earthquake loads and ensuring structural safety. The arrangement of channel steel 21 along the bridge's extension direction also facilitates adaptation to bridge temperature deformation, avoiding the adverse effects of temperature stress on the pavement system 2.

[0078] In some embodiments, the paving plate 22 is a patterned steel plate with a thickness of 5 mm or more.

[0079] In this invention, by using patterned steel plate as the paving material 22 and setting a thickness of 5 mm or more, the anti-slip safety and load-bearing reliability of the cantilevered pedestrian pavement are achieved. The raised patterns on the surface of the patterned steel plate increase the friction coefficient of the pavement, providing pedestrians with good anti-slip performance, especially in wet and slippery conditions such as rain and snow, effectively preventing pedestrians from slipping. The thickness of 5 mm or more ensures that the paving plate 22 has sufficient load-bearing capacity and deformation resistance, capable of withstanding pedestrian loads and other accidental loads, while also possessing good durability.

[0080] Specifically, the patterns on the surface of patterned steel plates are typically diamond-shaped, striped, or circular raised patterns. These raised patterns increase the surface roughness of the steel plate, improving friction with shoe soles and effectively preventing pedestrians from slipping. The pattern design also facilitates the rapid drainage of water from the road surface, keeping it dry. The 5mm thickness is based on an analysis of pedestrian load characteristics, considering normal pedestrian loads, concentrated crowd loads, and potential accidental loads such as those from bicycles and electric vehicles. At a thickness of 5mm, the section modulus of the patterned steel plate can withstand the bending moment generated by localized concentrated loads, keeping deformation within allowable limits. Simultaneously, the 5mm thickness provides sufficient rigidity, avoiding the localized dents or vibrations that are common with thinner plates.

[0081] In some embodiments, a pedestrian guardrail 6 is also included, disposed at the outer edge of the paving system 2.

[0082] In this invention, a pedestrian guardrail 6 is installed at the outer edge of the paving system 2, achieving the safety protection function of the cantilevered pedestrian walkway. The pedestrian guardrail 6, located at the outer edge, provides physical isolation and a sense of psychological security for pedestrians, effectively preventing accidental falls. Simultaneously, the pedestrian guardrail 6 provides lateral restraint to the cantilever structure, enhancing its overall stability. The choice of steel material ensures that the guardrail has sufficient strength and good durability.

[0083] Specifically, the pedestrian guardrail 6 is positioned at the outer edge of the pavement system 2, providing protection for the outer boundary of the entire cantilevered pedestrian walkway and forming a clear safety boundary. When pedestrians walk on the cantilevered pedestrian walkway, the pedestrian guardrail 6 can prevent pedestrians from falling off the bridge due to accidents, which is especially important when the bridge is high. The height of the pedestrian guardrail 6 is typically designed to be 1.1-1.2 meters, meeting the standard requirements for pedestrian railings and effectively preventing accidental falls by adults. The installation of the pedestrian guardrail 6 also provides tactile guidance for visually impaired and other special groups, helping them to identify the boundaries of the pedestrian walkway. From a structural perspective, the connection between the pedestrian guardrail 6 and the pavement system 2 provides lateral restraint at the outer edge of the cantilever structure. Under horizontal loads such as wind loads, the pedestrian guardrail 6 can work in conjunction with the cantilever structure to improve the overall lateral resistance of the structure.

[0084] In some embodiments, a bridge railing 7 is also included, which is disposed on the railing base 5 of the bridge.

[0085] In this invention, by installing a bridge railing 7 on the bridge railing foundation 5, safe isolation and protection are achieved between the cantilevered pedestrian walkway and the roadway. The bridge railing 7, installed on the bridge railing foundation 5, utilizes the existing structure and location of the foundation 5, providing vehicle collision protection for the cantilevered pedestrian walkway. This effectively prevents vehicles from accidentally entering the pedestrian walkway or colliding with the cantilever structure. Simultaneously, the installation of the bridge railing 7 also improves the safety protection system of the entire pedestrian walkway system, forming a complete safety barrier.

[0086] Specifically, the design of bridge railing 7, installed on bridge railing foundation 5, fully utilizes the existing bridge railing foundation 5 facilities, avoiding the complex engineering of re-setting the foundation. The railing foundation 5 typically possesses good structural strength and stability, providing reliable support for the bridge railing 7. The main function of bridge railing 7 is to prevent vehicles from running off the roadway and into the pedestrian area, especially preventing vehicles from impacting the cantilever structure and protecting its safety. The design of bridge railing 7 needs to consider energy absorption and transmission during vehicle impacts. Through reasonable structural design and material selection, the railing can withstand a certain level of vehicle impact without severe deformation or damage. Simultaneously, the connection between bridge railing 7 and the original bridge railing system forms a continuous protective line, eliminating protective gaps and improving the overall protective effect.

[0087] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0088] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A cantilevered pedestrian walkway structure for bridges, characterized in that, include: Multiple support systems (1) are provided at intervals along the extension direction of the bridge, and each support system (1) includes: A support mechanism (11) is provided, one end of which is connected to the bridge and the other end extends outward from the bridge to form a support section. A crossbeam (12) is provided on the support part of the support mechanism (11), and one end of the crossbeam (12) adjacent to the bridge is connected to the bridge. Paving system (2), which is laid on multiple beams (12) to form a cantilevered pedestrian pavement with a cantilever length of more than 1.0 meter.

2. The bridge cantilever pedestrian walkway cantilever structure according to claim 1, characterized in that, The support mechanism (11) includes: A supporting steel plate (111) is provided, one end of which is connected to the bridge and the other end extends outward to form the supporting part. An anchoring stiffening steel plate (112) is connected to the supporting steel plate (111), and the anchoring stiffening steel plate (112) is connected to the superstructure of the bridge.

3. The bridge cantilever pedestrian walkway cantilever structure according to claim 2, characterized in that, The anchoring stiffening steel plate (112) includes: The first plate (1121) is disposed at the end of the supporting steel plate (111) and is connected to the web plate (3) of the upper structure by the first fastener (113). The second plate (1122) is connected to the first plate (1121). The second plate (1122) is disposed above the supporting steel plate (111) and is connected to the wing plate (4) of the upper structure by the second fastener (114).

4. The bridge cantilever pedestrian walkway cantilever structure according to claim 3, characterized in that, The first fastener (113) and the second fastener (114) are anchored using rebar anchoring technology, with an anchoring depth of more than 12 centimeters.

5. The bridge cantilever pedestrian walkway cantilever structure according to claim 2, characterized in that, The supporting steel plate (111) and the anchoring stiffening steel plate (112) are connected by penetration welding.

6. The bridge cantilever pedestrian walkway cantilever structure according to claim 1, characterized in that, The crossbeam (12) includes: I-beam (121) is provided on the support part; A cantilever stiffening steel plate (122) is provided at the end of the I-beam (121) near the bridge. The cantilever stiffening steel plate (122) is connected to the guardrail foundation (5) of the bridge by a third fastener (123).

7. The bridge cantilever pedestrian walkway cantilever structure according to claim 6, characterized in that, The I-beam (121) and the cantilever stiffening plate (122) are connected by penetration welding.

8. The bridge cantilever pedestrian walkway cantilever structure according to any one of claims 1-7, characterized in that, The distance between two adjacent support systems (1) is within 1.5 meters.

9. The bridge cantilever pedestrian walkway cantilever structure according to claim 1, characterized in that, The paving system (2) includes: Multiple channel steels (21) are laid on the crossbeam (12) and fixedly connected to the crossbeam (12). The channel steels (21) are arranged along the extension direction of the bridge. Paving slab (22) is laid on the multiple channel steels (21).

10. The bridge cantilever pedestrian walkway cantilever structure according to claim 9, characterized in that, The paving plate (22) is a patterned steel plate with a thickness of 5 mm or more.

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