Construction method of anti-typhoon sea wave sea-crossing steel trestle and platform adjacent to residential building

Abstract

The invention relates to a construction method of an anti-typhoon sea wave sea-crossing steel trestle and platform adjacent to a residential building. The construction method comprises the steps that firstly, deep fusion application of BIM and VR is conducted; step 2, surveying and setting out; step 3, embedding steel bars and pouring strip-shaped concrete; fourthly, the steel pipe piles are transported and lengthened; fifthly, steel pipe piles are driven; sixthly, parallel connection and diagonal bridging construction is conducted; seventhly, bearing beams are installed; eighthly, longitudinal beams are installed; ninthly, the distribution beams are installed; tenthly, bridge deck slabs and guardrails are installed; and 11, an intelligent monitoring and early warning system.

Description

Technical Field

[0001] The invention relates to the field of offshore construction and highway bridges, and in particular to a construction method for a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings. Background Art

[0002] The topography at the bottom of the steel pipe pile foundation during the construction of steel trestles and steel platforms is complex. The covering layer at piles 1-1 to 2-1 is 0m to 3m, the covering layer at piles 2-14 to 3-1 is 3m to 1m, and piles 3-4 to 5-7 have no covering layer or a thin covering layer, resulting in the pile foundation being basically on the reef, making the construction of steel pipe piles extremely difficult.

[0003] Due to the complex geological conditions in coastal areas, the uneven distribution of reefs leads to instability in the pile sinking process, increasing the difficulty of construction.

[0004] Typhoon winds and waves have a significant impact on the steel trestle, affecting the overall stability of the steel trestle structure and operational safety during construction.

[0005] A typhoon is a strong form of tropical cyclone, with winds in the center reaching level 12 or above, and extremely high wind speeds. The winds generated pose a huge threat to steel trestles. The waves brought by typhoons are often very large. These huge waves not only have a huge impact force, but may also carry a large amount of silt and floating objects, causing further damage to the steel trestles. Typhoons usually last from a few hours to a few days, which means that steel trestles need to withstand the impact of strong winds and huge waves for a long time, increasing the risk of damage.

[0006] For the complex topography at the bottom of the steel pipe pile foundation, the traditional construction method is to use the direct pile foundation method or the drilling and implantation method for construction on the surface without cover or thin cover. However, these construction methods have some defects and shortcomings, such as: it is difficult to adapt to the complex and changeable geological conditions at the seaside. For example, in the area without cover or thin cover, the lateral friction resistance of the steel pipe pile is small, and it is easy to tilt or shift under the action of external forces such as wind and waves. Traditional construction methods often require a large amount of manpower and mechanical equipment, and the construction period is long, and it is easily affected by natural factors such as weather and sea conditions.

[0007] Typhoons and waves have a great impact on steel trestles, affecting the overall stability of the steel trestles structure. The traditional construction method is to install Bailey sheets after the construction of steel pipe piles to form the load-bearing structure of the trestles. The bridge deck is laid on the Bailey sheets to form a bridge deck for vehicles and personnel to pass. The bridge deck material is generally steel plates or reinforced concrete slabs, which are laid according to design requirements. However, these construction methods have some defects and shortcomings, such as: the steel trestles may not fully estimate the load requirements under extreme conditions such as typhoons during design, and they are often subjected to the impact of wave loads, resulting in insufficient bearing capacity of the structure when encountering strong winds and huge waves; the steel trestles resist impact loads through steel pipe piles, but due to the complex terrain and geological conditions, there may be insufficient bearing capacity, or even instability. Summary of the invention

[0008] The present invention aims to overcome the defects of the prior art and provide a construction method for a typhoon-resistant and wave-resistant sea-crossing steel trestle and platform adjacent to residential buildings, so as to solve the difficulties in steel pipe pile construction in areas with complex topography, the great impact of typhoons and waves during construction, the easy occurrence of abnormal situations such as overturning, and the problems affecting surrounding residential buildings.

[0009] In order to solve the above-mentioned technical problems, the present invention is achieved as follows:

[0010] A construction method for a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings, characterized in that it comprises the following steps:

[0011] Step 1: Deep integration and application of BIM (Building Information Modeling) technology and VR (Virtual Reality) technology;

[0012] Step 2: Measurement and setting out;

[0013] Step 3: Planting reinforcement and pouring strip concrete; Construction process: Construction preparation → Measurement and positioning → Planting reinforcement → Installation of pipe steel piles → Ebb tide, pouring strip foundation;

[0014] Step 4: Transportation and extension of steel pipe piles;

[0015] Step 5: Driving of steel pipe piles;

[0016] Step 6: Flat joint and scissor support construction;

[0017] Step 7: Installation of load-bearing beams;

[0018] Step 8: Installation of longitudinal beams;

[0019] Step 9: Distribution beam installation;

[0020] Step 10: Installation of bridge deck and guardrail;

[0021] Step 11: Intelligent monitoring and early warning system.

[0022] The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step one specifically includes: constructing a high-precision three-dimensional BIM model, which includes the geometric dimensions and structural layout of the steel trestle and the steel platform, and integrates detailed information such as material properties, construction sequence, and key node connections; introducing VR technology to construct a realistic virtual construction environment to improve the skill level of construction personnel, identify potential safety hazards in a risk-free environment, and enhance safety awareness;

[0023] Step 2 specifically includes: the surveyors calculate the coordinates and elevation of each steel pipe pile according to the trestle design drawings, set up monitoring stations at the control points on the river bank according to the calculation results, and conduct real-time monitoring and measurement during the construction of the steel pipe piles to ensure that each steel pipe pile is accurately positioned;

[0024] Step three specifically includes: According to the construction drawings, the bottom of the steel pipe piles in the area without covering layer or thin covering layer are reinforced by planting steel bars and pouring strip concrete. When constructing this process, the low tide time must be calculated. When the tide is low, the bottom of the steel pipe piles is lower than the sea level, and construction should be carried out during the low tide period.

[0025] The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step four specifically includes:

[0026] ①Steel pipe pile transportation

[0027] After the steel pipe piles are processed in the processing yard, they are transported to the construction site by trailers; railings or other obstacles are set up on both sides of the trailer to protect the steel pipe piles, and cables are used to tighten them to prevent them from falling; the piles should be stacked with multiple pads, and the pads should be placed evenly, and the top surfaces of the pads should be on the same plane; the steel pipe piles should be kept stable during stacking, transportation and lifting to avoid deformation of the steel pipe piles;

[0028] ②Steel pipe pile extension

[0029] The trailer transports the pile to the crawler crane, lifts the pile with the crawler crane hook, puts it into the pile driving frame and holds it tightly, and uses a special clamp to lift the steel pipe pile; the steel pipe pile is extended by full butt welding, and the weld is required to be full; when extending the steel pipe pile, the crawler crane lifts the steel pipe pile to be connected into place, and the construction workers take a small boat to carry out welding construction.

[0030] The method for constructing a typhoon-resistant and wave-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step five specifically includes: installing the guide frame for driving the steel pipe piles in place according to the center plane coordinates of the steel pipe piles calculated before construction, and after the steel pipe piles are positioned, using a crawler crane and a vibratory hammer to carry out construction.

[0031] The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step six specifically includes: after the steel pipe piles are driven, the flat joint and scissor brace construction begins; the flat joint and scissor brace are welded and connected by channel steel; first, the channel steel is hoisted to the top of the pile by a crawler crane, and then it is slowly hoisted to the designed position by manual command for welding, and the welding quality must be guaranteed during the construction process to ensure the use function of the flat joint and scissor brace;

[0032] Starting from the first section, the bridge deck height of the second section is 5.5m-8.2m, the bridge deck height of the third section is 8.2m-9.46m, the bridge deck height of the fourth section is 9.46m-12.22m, and the bridge deck height of the fifth section is 12.22m-14m.

[0033] The construction method of a typhoon-resistant and wave-resistant cross-sea steel trestle and platform adjacent to residential buildings is characterized in that step seven specifically includes: after confirming that the pile top elevation is correct through review, the I-beam load-bearing beam is lifted by a crane to the top of the steel pipe pile (in the slot), the beam is placed at the center of the steel pipe pile according to the design and adjusted to the level, and welded after passing the inspection.

[0034] The construction method of a typhoon-resistant and wave-resistant cross-sea steel trestle and platform adjacent to residential buildings is characterized in that step eight specifically includes: before erection, the Bailey beam or I-beam is processed in advance to a corresponding length according to the drawings; before erection, the surveyor uses a total station to restore the pile axis according to the design drawings and marks it on the head top plate; the installer installs the Bailey frame or I-beam according to the measured axis, and the longitudinal center axis coincides with the axis of the steel pipe pile.

[0035] The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step nine specifically includes: 1. After the Bailey beams of the main trestle and the branch trestle are installed for one span, I22a I-beams are laid on the Bailey beams with a spacing of 75 cm as transverse distribution beams. After the laying is completed, the Bailey beams and the distribution beams are connected by fixing iron clamps, and one is set every 2.0 meters according to the panel width, and connected by steel plate welding;

[0036] 2. After the Bailey beam of the piling platform is installed for one span, I22a is installed on the Bailey beam with a spacing of 30cm; one is set every 2.0 meters according to the width of the panel and welded with connecting steel plates.

[0037] The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings is characterized in that step ten specifically includes: 1. After the I-beam distribution beam of the main trestle is installed, a special bridge deck with a length of 6.0m×width of 2.0m×height of 0.15m is laid, and the special bridge deck is welded on the I-beam, and the bridge deck is connected to the steel plate for welding, with a weld length of 15cm and a width of 10cm to prevent the steel plate from curling back due to heavy vehicles;

[0038] 2. Pile driving platform: After the I-beam distribution beam is paved, the full length 6.0m × width 2.0m × height 0.01m patterned steel plate is used as the bridge deck, and the bridge deck is welded to the I-beam;

[0039] 3. Use channel steel as the bridge deck near the revetment; add cables or struts at the first and third stone steps to connect the pier and the steel trestle; add cables or struts at the fourth and fifth joints;

[0040] Cable pulling method: find reefs to drill holes, plant steel bars, and use steel cables to connect the trestle to the reefs according to the actual situation on site;

[0041] Support rod method: when the soil is shallow and there is no pulling point near the edge, support is used. The support material is steel or pipe. The model is determined according to the actual length. The excavator is used to tilt the soil and the upper end is welded to the side of the trestle.

[0042] Installation of handrails: After the panel is laid, welding of safety handrails on both sides shall be carried out in time; 1.2m high handrails are set on both sides of the bridge deck, handrail columns are made of I14 I-beams with a spacing of 2m, and handrails are arranged in three rows of A48×3mm steel pipes; handrails of the trestle are painted with yellow and black magnetic paint for warning; for the safety of vehicles and pedestrians, an 18cm high skirting board is set on the inner side of the handrail along the longitudinal direction of the bridge, and the material is a 3mm thick steel plate.

[0043] The beneficial effects of the present invention are as follows: It can be seen from the above technical solution that the present application provides a construction method for a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings, which has the following advantages:

[0044] Through the deep integration and application of BIM (Building Information Modeling) technology and VR (Virtual Reality) technology: a solid foundation is provided for the subsequent construction plan formulation, material procurement, resource allocation, etc. At the same time, by utilizing the visualization characteristics of BIM, complex construction plans are presented to all parties of the project, including owners, supervisors, construction personnel, etc., in the form of animation or virtual reality, making the construction plan more intuitive and easy to understand, and facilitating communication and decision-making.

[0045] VR technology is introduced to build a realistic virtual construction environment. It helps to improve the skill level of construction workers, identify potential safety hazards in a risk-free environment, and enhance safety awareness. By simulating various possible emergencies (such as wind and waves at sea, equipment failures, injuries, etc.), construction workers can conduct actual combat drills in a virtual environment and learn correct response measures and escape routes. It significantly improves the emergency response capabilities and self-protection awareness of construction workers. It provides strong support for safety education and emergency drills for offshore construction.

[0046] 3. During the construction process, BIM and VR technologies integrate a real-time monitoring system to compare and analyze the actual data of the construction site with the BIM model, and promptly detect deviations and issue warnings. At the same time, VR technology is used for remote monitoring and guidance, so that project managers can quickly understand the on-site situation and make accurate decisions and adjustments. In addition, according to changes in the construction progress, the BIM model can also be dynamically updated to ensure the flexibility and adaptability of the construction plan.

[0047] 4. The construction method of planting reinforcement and pouring strip concrete is adopted to make the structure have a higher load-bearing capacity. The steel pipe pile itself has excellent mechanical properties and load-bearing capacity, and the pouring of strip concrete further enhances the rigidity and strength of the pile body, so that the whole structure can withstand greater loads.

[0048] 5. The construction process of planting reinforcement and strip concrete pouring is relatively simple and quick, which can greatly shorten the construction period. In cross-sea construction, time is often a key factor, so this construction method helps to improve work efficiency and reduce construction time. At the same time, this method has strong environmental adaptability and can maintain the stability and safety of the structure in harsh marine environments.

[0049] 6. By setting up pull points or support points on both sides, the foundation structure of the embedded reinforcement and strip concrete pouring can be further reinforced to improve its overall rigidity. This reinforcement method can effectively resist horizontal loads such as wind and water flow, and prevent the structure from horizontal displacement or tilting.

[0050] 7. After the reinforcement and strip concrete are poured, although the structure has a certain bearing capacity, there is still a risk of collapse in some extreme cases (such as strong storms, earthquakes, etc.). By setting up pulling points or support points on both sides, this risk can be reduced and the safety during the construction process can be improved. At the same time, it has the advantages of ensuring the safety of construction workers, speeding up the construction progress, reducing the difficulty of construction, reducing long-term deformation, and extending the service life.

[0051] 8. The crawler crane is used for construction, which has good stability and carrying capacity, and can cope with various complex terrains and heavy lifting requirements. The crawler crane can move and operate flexibly on narrow or uneven ground, and has strong adaptability. At the same time, the crawler crane is equipped with complete safety protection devices, such as torque limiters, height limiters, etc., which can ensure safety during the construction process.

[0052] 9. The DZ-60 vibratory hammer uses the principle of high-frequency vibration, which can quickly drive steel pipe piles into the ground and improve construction efficiency. Compared with the traditional impact piling method, the vibration hammer produces less noise and vibration, and has less impact on the surrounding environment and residential buildings. The two work together to greatly improve construction efficiency. Through the precise control of the vibration hammer, the driving depth and verticality of the steel pipe piles can be ensured, while also reducing construction costs and improving economic benefits.

[0053] 10. By optimizing the design stage, the height of the bridge deck is raised to avoid the impact of waves. The use of channel steel as the bridge deck increases the penetration rate of waves, ensures the stability of the structure, and greatly reduces the impact of loads. Cables or struts are added at the first and third joints of the stone steps to connect the pier and the steel trestle. Cables or struts are added at the fourth and fifth joints to enhance the steel trestle's ability to resist overturning and backwash.

[0054] 11. The intelligent monitoring and early warning system integrates a variety of advanced technologies, including satellite positioning measurement, total station, sensors, wireless communication technology, remote video monitoring, etc., to achieve comprehensive and accurate monitoring and management of the entire construction process. Real-time collection and transmission of various data on the construction site, including displacement, stress, environmental parameters, etc., provide a scientific basis for construction decision-making, achieve comprehensive monitoring and management of the entire construction process, and improve construction quality and safety.

[0055] 12. Reduce the impact of construction on nearby residential buildings by adopting relevant measures such as selecting low-noise equipment, reducing noise, installing sound insulation facilities, and controlling water pollution, light pollution, and traffic impact. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments:

[0057] Figure 1 It is a schematic diagram of the process of the present invention;

[0058] Figure 2 This is a schematic diagram of the extension of steel pipe piles on site;

[0059] Figure 3 This is a schematic diagram of the connection between the flat joint, scissor brace and steel pipe pile;

[0060] Figure 4 This is a schematic diagram of the installation of the load-bearing beam;

[0061] Figure 5 Schematic diagram for installation of Bailey beam and distribution beam;

[0062] Figure 6 This is the plan view of the bridge deck;

[0063] Figure 7 This is a schematic diagram of the steel trestle plan layout;

[0064] Figure 8 This is a schematic diagram of the steel trestle facade layout;

[0065] Fig. 9 This is a cross-section diagram of the first section of the steel trestle;

[0066] Fig.10 This is a schematic diagram of the longitudinal section of the first section of the steel trestle;

[0067] Fig.11 This is a schematic diagram of the second and fourth cross-sections of the steel trestle;

[0068] Fig.12 This is a schematic diagram of the second and fourth longitudinal sections of the steel trestle;

[0069] Fig.13 This is a cross-section diagram of the third section of the steel trestle;

[0070] Fig.14 This is a schematic diagram of the longitudinal section of the third section of the steel trestle;

[0071] Fig.15 This is a cross-section diagram of the fifth section of the steel trestle;

[0072] Fig.16 This is a schematic diagram of the longitudinal section of the fifth section of the steel trestle;

[0073] Fig.17 This is a schematic diagram of the starting point guide for the first section of the steel trestle;

[0074] Fig.18 This is a schematic diagram of the guidance of the fifth terminal of the steel trestle;

[0075] Fig.19 This is the Bailey beam layout for the steel platform;

[0076] Fig. 20 Assign beam layout plans to steel platforms;

[0077] Fig.21 This is the standard section layout drawing of the steel platform. DETAILED DESCRIPTION

[0078] The technical solutions of the embodiments of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field without creative work based on the embodiments in the embodiments of the present application are within the scope of protection requested by the present application.

[0079] like Figure 1 , 7, 8, and 21 show: A construction method for a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings, comprising the following steps:

[0080] Step 1: Deep integration and application of BIM (Building Information Modeling) technology and VR (Virtual Reality) technology;

[0081] ① Before the construction started, the project team used BIM technology to conduct detailed preliminary planning. By collecting information such as marine environmental data, geological exploration reports, design specifications and project requirements, a high-precision three-dimensional BIM model was constructed. This model includes the geometric dimensions and structural layout of the steel trestle and steel platform, and integrates detailed information such as material properties, construction sequence, and key node connections. The completion of three-dimensional modeling provides a solid foundation for subsequent construction plan formulation, material procurement, and resource allocation.

[0082] ② Based on the established 3D BIM model, the project team compares and optimizes multiple plans. By simulating the construction process, material consumption, construction schedule, etc. under different construction plans, the optimal solution is found. At the same time, using the visualization characteristics of BIM, the complex construction plan is presented to all parties of the project, including the owner, supervisor, construction personnel, etc. in the form of animation or virtual reality, making the construction plan more intuitive and easy to understand, and facilitating communication and decision-making.

[0083] ③ VR environment construction and simulation operation

[0084] On the basis of BIM model, VR technology is further introduced to build a realistic virtual construction environment. After wearing VR equipment, construction workers can enter the virtual steel trestle and steel platform construction site "immersively". In the virtual environment, construction workers can perform simulated assembly, welding, hoisting and other operations to familiarize themselves with the construction process and operation points in advance. This simulated operation not only helps to improve the skill level of construction workers, but also can identify potential safety hazards in a risk-free environment and enhance safety awareness.

[0085] ④ Safety education and emergency drills: By simulating various possible emergency situations (such as wind and waves at sea, equipment failure, personnel injuries, etc.), construction workers can conduct actual combat drills in a virtual environment and learn the correct response measures and escape routes. This immersive safety education method can significantly improve the emergency response capabilities and self-protection awareness of construction workers, providing strong support for safety education and emergency drills for offshore construction.

[0086] ⑤Construction monitoring and dynamic adjustment

[0087] During the construction process, BIM and VR technologies integrate a real-time monitoring system to compare and analyze the actual data of the construction site with the BIM model, and promptly detect deviations and issue warnings. At the same time, VR technology is used for remote monitoring and guidance, so that project managers can quickly understand the on-site situation and make accurate decisions and adjustments. In addition, according to changes in the construction progress, the BIM model can also be dynamically updated to ensure the flexibility and adaptability of the construction plan.

[0088] Step 2: Measurement and setting out;

[0089] According to the design drawings of the trestle, the surveyors calculated the coordinates and elevation of each steel pipe pile, set up monitoring stations at the control points on the river bank according to the calculation results, carried out real-time monitoring and measurement during the construction of the steel pipe piles, ensured the accurate positioning of each steel pipe pile, and kept good construction measurement records. The surveyors should strictly control the distance between the center line of the trestle and the center of the bridge position according to the design drawings to prevent the axis deviation from affecting the use function of the steel trestle.

[0090] Step 3: Planting reinforcement and pouring strip concrete;

[0091] According to the construction drawings, the bottom of the steel pipe piles in the area without cover or thin cover are reinforced by planting steel bars and pouring strip concrete. The low tide time must be calculated during the construction of this process. When the tide is low, the bottom of the steel pipe piles is lower than the sea level, and the construction should be carried out during the low tide period.

[0092] Construction process: Construction preparation → Measurement and positioning → Rebar planting → Steel pipe pile installation → Ebb tide, pouring strip foundation.

[0093] ① Use the necessary machinery, equipment, materials and electricity for construction, including using the excavator head to chisel the bottom flat.

[0094] ②Measurement and positioning: Based on the given guide wire points, the total station is used to measure and set the pile positions during construction.

[0095] ③Rebar embedding: Use an electric drill to drill holes with a depth of 30cm and a diameter of 25mm. Drill 8 holes at each pile position, evenly distributed along the outer circle of the steel pipe pile. Use rebar embedding glue to embed the rebar, with the steel bars inserted 30cm into the rock and 30cm exposed.

[0096] ④ Installation of steel pipe piles: After the anchor bar strength meets the requirements, use a crawler crane to transport the steel pipe piles to the designed position and weld them firmly to the anchor bar.

[0097] ⑤ When the tide recedes, cast the strip foundation: After the steel pipe piles are installed, install a 1.2m wide and 0.4m high (the main trestle is 6m long, and the length of the piling platform is determined according to the horizontal width of the bridge deck) formwork and cast the C30 concrete strip foundation.

[0098] ⑥ Find pulling or supporting points on both sides of each pier to reinforce the foundation.

[0099] Calculation of steel pipe pile embedment points:

[0100] The steel pipe pile embedding point adopts the formula 4.3.2 of the port engineering pile foundation specification

[0101] t=ηT

[0102] Where:

[0103] t: Depth of bending embedding point from the beach surface

[0104] η: coefficient, 1.8-2.2, value 2.0

[0105] T: Relative stiffness characteristic value of the pile, calculated by formula in Appendix D3.3-3

[0106]

[0107] m: According to Appendix Table D.3.1, the value is 3750KN / m 4

[0108] b o :Use formula D.3.2-2

[0109] b o =Kf×(1.5d+0.5)=0.9×(1.5×0.426+0.5)=1.0m

[0110] Kf: round pile or pipe pile, the value is 0.9m.

[0111] d: Pile diameter or the width of the pile perpendicular to the direction of horizontal external force, with a value of 0.426

[0112] Substitute the above values ​​into formula D3.3-3 and we get T = 1.67m

[0113] For piles that bear horizontal forces or moments, the depth of burial should meet the conditions of elastic long piles and should not be less than 4T>L≥2.5

[0114] Table 4.3.1 Classification criteria for elastic long piles, medium-long piles and rigid piles

[0115]

[0116] Note: t ——the depth of the pile into the soil (m);

[0117] T——Relative stiffness characteristic value of the pile (m), calculated according to Appendix D.

[0118] That is, the minimum depth of soil is l = 1.67 × 2.5 = 4.2m.

[0119] The minimum penetration depth of A426 and A506 steel pipe piles is 4.2m.

[0120] The construction method of planting reinforcement and strip concrete pouring makes the structure have a higher load-bearing capacity. The steel pipe pile itself has excellent mechanical properties and load-bearing capacity, and the pouring of strip concrete further enhances the rigidity and strength of the pile body, allowing the entire structure to withstand greater loads. The construction process of planting reinforcement and strip concrete pouring is relatively simple and fast, which can greatly shorten the construction period. In cross-sea construction, time is often a key factor, so this construction method helps to improve work efficiency and reduce construction time. At the same time, this method has strong environmental adaptability and can maintain the stability and safety of the structure in harsh marine environments.

[0121] By setting pull points or support points on both sides, the foundation structure of the embedded reinforcement and strip concrete pouring can be further reinforced to improve its overall rigidity. This reinforcement method can effectively resist horizontal loads, such as wind, water flow, etc., to prevent the structure from horizontal displacement or tilting. After the embedded reinforcement and strip concrete pouring, although the structure has a certain bearing capacity, there is still a risk of collapse in certain extreme cases (such as severe storms, earthquakes, etc.). By setting pull points or support points on both sides, this risk can be reduced and the safety during the construction process can be improved. At the same time, it has the advantages of ensuring the safety of construction workers, speeding up the construction progress, reducing the difficulty of construction, reducing long-term deformation, and extending the service life.

[0122] Step 4: Transportation and extension of steel pipe piles;

[0123] ①Steel pipe pile transportation

[0124] After the steel pipe piles are processed in the processing yard, they are transported to the construction site by trailers. Railings or other obstacles are set up on both sides of the trailer to protect the steel pipe piles, and cables are used to tighten them to prevent them from falling; the piles should be stacked with multiple pads, and the pads should be placed evenly, and the top surfaces of the pads should be on the same plane; the steel pipe piles should be kept stable during stacking, transportation and lifting to avoid deformation of the steel pipe piles.

[0125] ②Steel pipe pile extension, such as Figure 2 As shown:

[0126] The trailer transports the pile to the crawler crane, lifts the pile with the crawler crane hook, puts it into the pile driving frame and holds it tightly, and lifts the steel pipe pile with a special clamp. The steel pipe pile extension adopts butt welding, and the weld is required to be full. When the steel pipe pile is extended, the crawler crane lifts the steel pipe pile to be connected into place, and the construction workers take a small boat to carry out welding construction.

[0127] During the construction process, the following process is followed when extending:

[0128] a. Interface cleaning: Before the steel pipe piles are connected, some processing work should be done, mainly cutting the area damaged by the vibrating hammer clamps during the installation process, with the cutting length not less than 50cm; then clean the rust, iron oxide and oil stains within 30mm on both sides of the steel pipe pile interface to reveal the metallic luster of the steel.

[0129] b. Welding: The two steel pipe joints are butt welded and the welding is manual. According to the welding process requirements, the welding direction sequence, welding current and weld size should be controlled. The depth of each weld metal or the maximum width of the weld should not exceed the width of the weld surface. The same weld should be welded continuously and completed in one go. Then the reinforcement steel plate (6 pieces of 20cm×40cm steel plates for each joint) should be welded.

[0130] c. Weld cleaning and treatment: After welding is completed, clean the slag and metal splashes on the weld surface, and the welder will check the appearance quality of the weld by himself; if it does not meet the requirements, it should be repaired or polished. The repaired weld should be smooth and round, and will not affect the appearance quality requirements of the original weld.

[0131] d. Welding environment: humidity should not be higher than 80%; temperature should not be lower than 0℃.

[0132] The allowable deviation of the pipe joint shape and the allowable deviation of the adjacent pipe joints shall comply with the provisions of the following table:

[0133] Permissible deviation of pipe joint dimensions

[0134] project Allowable deviation (mm) perimeter ±0.5% of the circumference, and not more than 10 Pipe end ovality 0.5%D, and not more than 5 Pipe end flatness 2 Pipe end plane tilt Less than 0.5%D and not more than 4

[0135] Adjacent pipe joints allowable deviation

[0136] project Allowable deviation (mm) illustrate Pipe diameter ≤3 Expressed as the difference in the circumference of the pipe segment, the secondary difference ≤ 3π (mm) Height difference of butt plate ＜1

[0137] The allowable deviation of weld appearance shall comply with the following table:

[0138] Permissible deviation of weld appearance

[0139]

[0140]

[0141] Step 5: Driving of steel pipe piles;

[0142] According to the center plane coordinates of the steel pipe pile calculated before construction, the guide frame for steel pipe pile driving is installed in place. After the steel pipe pile is positioned, the crawler crane and DZ-60 vibratory hammer are used for construction. According to the center plane coordinates of the steel pipe pile calculated before construction, rough positioning is performed. Use crawler crane and DZ-60 vibratory hammer for construction.

[0143] Crawler Crane Wheel Pressure

[0144] According to the relevant provisions of the Crane Design Specifications (GB / T 3811-2008), the total load of the crawler crane on the side or on the overturning line of the chassis end supporting the minimum load should not be less than 15% of the total gravity of the crane. However, the weight of the hoisted object in this scheme is quite different from the deadweight of the crane itself, so the total load for side lifting or forward tilting is taken as 70%.

[0145] When lifting on the side

[0146]

[0147] When hoisting in front

[0148] When the crane is lifting the load directly in front of it, according to the most unfavorable working condition, the load of the crane crawler acting on the bridge deck is distributed in a triangle along the length of the crawler;

[0149]

[0150] During the pile foundation construction process, noise barriers or sound barriers are set up around the construction site to block and reduce the spread of noise.

[0151] After the steel pipe pile enters the riverbed under its own gravity and the vibrating hammer, the plane position of the steel pipe pile is re-measured and set. When the requirements are met, the vibrating hammer is started to vibrate the steel pipe pile into the riverbed. During the vibration process, the management personnel observe the verticality of the pipe pile in the longitudinal and transverse directions through the total station and the hammer ball, and command the crawler crane to swing forward and backward and left and right through the intercom to adjust the verticality of the steel pipe pile. When the steel pipe pile enters the riverbed 2 to 3 meters, and its plane position and verticality basically do not change, the hook can be loosened to allow the steel pipe pile to continue to vibrate into the strongly weathered rock under the action of the vibrating hammer. The judgment standard is that the penetration of the heavy steel pipe pile during the injection process is 0cm / min or the steel pipe pile jumps up and down to judge the rock. At the same time, it is necessary to combine the geological survey map to assist in confirming whether the rock has been reached.

[0152] Each steel pipe pile should be sunk in one go without any pause or long intervals, so as to avoid the soil around the pile recovering and causing difficulty in further sinking. During the sinking process, the measuring instrument should monitor the verticality at any time. During the sinking process, the measurement and monitoring should be carried out, and the sinking records should be kept. The verticality of the steel pipe pile is mainly controlled by the vibrating hammer fixture and the guide frame. The verticality control is mainly prevention, supplemented by correction. The observation density should be appropriately increased to understand the sinking status at any time. If the steel pipe pile is found to have a tilting trend when sinking, take appropriate measures to adjust the verticality in time.

[0153] Things to note during pile sinking construction:

[0154] ①During the construction of steel pipe piles, the pile top elevation should be strictly controlled, and the verticality of the steel pipe piles should meet the requirement of <1%.

[0155] ②The steel pipe piles are positioned using a total station.

[0156] ③ When the pile is first inserted into the soil, it sinks by its own weight. Check the position in time. If a large tilt occurs in the initial stage of pile sinking (1m to 2m), correct it in time or pull it out and re-insert it.

[0157] ④ The plane position deviation of steel pipe piles shall be controlled in accordance with the relevant provisions of the Technical Specifications for Highway Bridge and Culvert Construction (JTG / T F50-2011). The specific provisions are shown in the following table:

[0158] Steel pipe pile control matters

[0159]

[0160] ⑤ The piles that have been sunk should be installed and connected in time according to the design requirements to shorten the bearing time of single piles as much as possible.

[0161] ⑥ During the construction of the steel trestle, ensure that safety signs for water construction are in place.

[0162] The crawler crane construction has good stability and carrying capacity, and can cope with various complex terrains and heavy lifting requirements. The crawler crane can move and operate flexibly on narrow or uneven ground, and has strong adaptability. At the same time, the crawler crane is equipped with complete safety protection devices, such as torque limiters, height limiters, etc., to ensure safety during the construction process. The DZ-60 vibratory hammer adopts the principle of high-frequency vibration, which can quickly drive steel pipe piles into the ground and improve construction efficiency. Compared with the traditional impact piling method, the vibratory hammer produces less noise and vibration, and has less impact on the surrounding environment. The coordinated operation of the two can greatly improve the construction efficiency. Through the precise control of the vibratory hammer, the driving depth and verticality of the steel pipe piles can be ensured, while also reducing construction costs and improving economic benefits.

[0163] Step 6: Flat joint and scissor support construction; Figure 3 , 9 -18 shows:

[0164] After the steel pipe piles are driven, the construction of flat joints and scissor braces begins. Flat joints and scissor braces are welded and connected with 20 channel steel. First, the channel steel is hoisted to the top of the pile by a crawler crane, and then it is slowly hoisted to the designed position for welding under manual control. The welding quality must be guaranteed during the construction process to ensure the use function of the flat joints and scissor braces.

[0165] Starting from the first section, the bridge deck height of the second section is 5.5m-8.2m, the bridge deck height of the third section is 8.2m-9.46m, the bridge deck height of the fourth section is 9.46m-12.22m, and the bridge deck height of the fifth section is 12.22m-14m.

[0166] By optimizing during the design phase, the height of the bridge deck can be raised to avoid the impact of waves.

[0167] Step 7: Installation of load-bearing beams; Figure 4 As shown:

[0168] After verifying and confirming that the pile top elevation is correct, the I-beam load-bearing beam is lowered to the top of the steel pipe pile (inside the slot) by a crane. The beam is placed in the center of the steel pipe pile according to the design and adjusted to the level. It is welded after inspection and approval.

[0169] Step 8: Installation of longitudinal beams;

[0170] Before erection, the Bailey beam or I-beam is processed in advance according to the drawings. Before erection, the surveyor uses a total station to restore the pile axis according to the design drawings and marks it on the top plate of the head. The installer installs the Bailey frame or I-beam according to the measured axis, and the longitudinal center axis coincides with the axis of the steel pipe pile.

[0171] Step 9: Distribution beam installation; Figure 5 , 19 , as shown in 20:

[0172] ① After the installation of one span of Bailey beams of the main trestle and the branch trestle is completed, I22a I-beams are laid on the Bailey beams with a spacing of 75cm as transverse distribution beams. After laying, the Bailey beams and distribution beams are connected with fixed clamps, one for every 2.0 meters according to the width of the panel, and connected by steel plates for welding.

[0173] ②After the Bailey beam of the piling platform is installed for one span, I22a is installed on the Bailey beam with a spacing of 30cm. One is set every 2.0 meters according to the width of the panel and welded with connecting steel plates.

[0174] Step 10: Installation of bridge deck and guardrails; Figure 6 As shown:

[0175] After the installation of the I-beam distribution beam of the main trestle bridge is completed, a special bridge deck with a length of 6.0m, a width of 2.0m and a height of 0.15m is laid. The special bridge deck is welded to the I-beam and the bridge deck is connected to the steel plate for welding. The weld length is 15cm and the width is 10cm to prevent the steel plate from curling back due to the passage of heavy vehicles.

[0176] ②Piling platform: After the I-beam distribution beam is paved, the full length 6.0m × width 2.0m × height 0.01m patterned steel plate is laid as the bridge deck, and the bridge deck is welded to the I-beam.

[0177] ③Use channel steel as the bridge deck near the revetment. Add cables or struts at the first and third stone steps to connect the wharf and the steel trestle. Add cables or struts at the fourth and fifth joints.

[0178] Cable pulling method: find reefs to drill holes, plant steel bars, and use steel cables to connect the trestle to the reefs according to the actual situation on site;

[0179] Support rod method: When the soil is shallow and there is no pulling point near the edge, support is used. The support material is steel or pipe. The model is determined according to the actual length. Use an excavator to tilt it into the soil and weld the upper end to the side of the trestle.

[0180] Railing installation: After the panel is laid, the safety guardrails on both sides must be welded in time. 1.2m high guardrails are set on both sides of the bridge deck. The guardrail columns are made of I14 I-beams with a spacing of 2m. The railings are arranged in three rows of A48×3mm steel pipes. The trestle railings are painted with yellow and black magnetic paint for warning. For the safety of vehicles and pedestrians, an 18cm high skirting board is set on the inner side of the railing along the longitudinal direction of the bridge. The material is a 3mm thick steel plate.

[0181] The use of inverted channel steel as the bridge deck increases the penetration rate of waves, ensures structural stability, and greatly reduces the impact of loads. Cables or struts are added at the first and third joints of the stone steps to connect the pier and the steel trestle. Cables or struts are added at the fourth and fifth joints to enhance the steel trestle's ability to resist overturning and backwash.

[0182] Step 11: Intelligent monitoring and early warning system.

[0183] (1) Sensor installation: The installation of displacement sensors and stress sensors is carried out simultaneously during the construction of the steel trestle and steel platform.

[0184] Upper chord of steel trestle: Install strain sensors at the maximum stress position to monitor its stress state.

[0185] Lower chord of steel trestle: Sensors are also installed at the maximum stress position to monitor its stress conditions.

[0186] Steel trestle web member: The web member is an important part connecting the upper chord and the lower chord, and sensors are installed at its key positions.

[0187] Steel trestle beams (including upper beams and lower beams): The beams are subject to large bending moments and shear forces, and sensors should be installed at key locations such as the mid-span and supports of the beams.

[0188] Cantilever beam of steel trestle: The cantilever beam part needs special attention because its cantilever structure is prone to generate large stress. Sensors should be installed at the free end and root of the cantilever beam.

[0189] Node parts of steel trestle: The nodes of steel trestle are the key parts of structural connection and also the places where stress is concentrated. Sensors should be installed at the nodes to monitor their stress conditions.

[0190] Steel trestle foundation: Steel pipe piles or other foundation structures are the key to the stability of the steel trestle. Displacement sensors should be installed on the foundation to monitor their displacement.

[0191] Platform support structure:

[0192] The platform support structure includes columns, beams, etc. These parts bear the entire load of the platform. Sensors need to be installed at their key positions to monitor their stress, displacement and other parameters.

[0193] Platform panel: For large-area platform panels, sensors are installed at the mid-span, edges and other locations to monitor their deformation and stress conditions.

[0194] Connection parts: The connection parts between the platform and the supporting structure are where stress is concentrated and where damage is prone to occur. Sensors are installed at these parts for monitoring.

[0195] (2) Installation of environmental parameter sensors: In order to monitor the environmental parameters (such as temperature, humidity, wind speed, etc.) during the construction process, environmental parameter sensors are installed near the steel trestle and steel platform.

[0196] (3) Remote monitoring and management: Through high-definition network cameras, network hard disk recorders and other equipment, the construction site can be monitored around the clock without blind spots.

[0197] (4) Data transmission and storage: Use mobile communications, satellite communications, or wireless LAN technologies to transmit the collected data to a data center or monitoring center. Ensure the stability and reliability of the wireless communication network to avoid data loss due to signal interruption. Set up a dedicated data center or server to store and process the collected data.

[0198] (5) Build a digital and visual management platform to display real-time images and data of the construction site on the screen to facilitate remote monitoring and management by management personnel.

[0199] (6) Establishment of early warning mechanism: According to construction requirements and safety regulations, set reasonable early warning thresholds. When the monitoring data exceeds the early warning threshold, the system automatically sends out an early warning signal and notifies relevant personnel through SMS, email, etc.

[0200] The measures of the present invention for reducing the impact of construction on nearby residential buildings are as follows:

[0201] (1) Noise pollution Use low-noise equipment: Before construction, use low-noise construction equipment as much as possible to reduce noise sources. Reasonable arrangement of construction time: Avoid high-noise operations during residents' rest time (such as at night and during lunch breaks), and try to arrange noisy operations during the day. Set up sound insulation facilities: Set up sound insulation barriers or sound barriers around the construction site to block and reduce the spread of noise.

[0202] (2) Water pollution

[0203] Offshore construction may generate pollutants such as wastewater, waste oil and solid waste. If not handled properly, it may cause pollution to nearby sea areas and residents' water.

[0204] Strict sewage management: Establish a strict sewage management system to ensure that construction wastewater, waste oil and solid waste are properly handled and not discharged at will. Set up anti-pollution facilities: Set up anti-pollution facilities around the construction site, such as oil collection pools, wastewater treatment pools, etc., to collect and treat pollutants generated during the construction process. Strengthen monitoring: Regularly monitor the water quality in the construction area to ensure that the water quality meets environmental protection requirements.

[0205] (3) Light pollution: Lighting equipment used during nighttime construction may generate light pollution, affecting the nighttime rest and sleep of nearby residents.

[0206] Solution: Arrange lighting equipment reasonably: avoid directly shining lighting equipment into residential areas, and reduce light pollution by adjusting lighting angles and setting up sunshades.

[0207] Use low-brightness lighting equipment: When carrying out construction at night, use low-brightness, low-glare lighting equipment to reduce the impact on residents.

[0208] (4) Traffic impact:

[0209] During construction, the entry and exit of large construction vehicles and equipment may put pressure on nearby traffic, causing traffic congestion and safety hazards. Optimize traffic organization: formulate a reasonable traffic organization plan to ensure that the entry and exit of construction vehicles and equipment does not affect the normal operation of nearby traffic. Set up traffic signs: set up obvious traffic signs and warning signs around the construction site to remind passing vehicles and pedestrians to pay attention to the safety of the construction area. Strengthen traffic management: dispatch more traffic management personnel to guide and manage the traffic around the construction site to ensure safe and smooth traffic.

[0210] The above are only embodiments provided for the present application and are not intended to limit the present application. Although the present application is described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A construction method for a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings, characterized in that It includes the following steps: Step 1: Deep integration and application of BIM (Building Information Modeling) technology and VR (Virtual Reality) technology; Step 2: Measurement and setting out; Step 3: Planting reinforcement and pouring strip concrete; Construction process: Construction preparation → Measurement and positioning → Planting reinforcement → Installation of pipe steel piles → Ebb tide, pouring strip foundation; Step 4: Transportation and extension of steel pipe piles; Step 5: Driving of steel pipe piles; Step 6: Flat joint and scissor support construction; Step 7: Installation of load-bearing beams; Step 8: Installation of longitudinal beams; Step 9: Distribution beam installation; Step 10: Installation of bridge deck and guardrail; Step 11: Intelligent monitoring and early warning system.

2. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1 is characterized in that: Step 1 specifically includes: building a high-precision three-dimensional BIM model, which includes the geometric dimensions and structural layout of the steel trestle and steel platform, and integrates detailed information such as material properties, construction sequence, and key node connections; introducing VR technology to build a realistic virtual construction environment to improve the skills of construction workers, identify potential safety hazards in a risk-free environment, and enhance safety awareness; Step 2 specifically includes: the surveyors calculate the coordinates and elevation of each steel pipe pile according to the trestle design drawings, set up monitoring stations at the control points on the river bank according to the calculation results, and conduct real-time monitoring and measurement during the construction of the steel pipe piles to ensure that each steel pipe pile is accurately positioned; Step three specifically includes: According to the construction drawings, the bottom of the steel pipe piles in the area without covering layer or thin covering layer are reinforced by planting steel bars and pouring strip concrete. When constructing this process, the low tide time must be calculated. When the tide is low, the bottom of the steel pipe piles is lower than the sea level, and construction should be carried out during the low tide period.

3. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1 is characterized in that: Step 4 specifically includes: ①Steel pipe pile transportation After the steel pipe piles are processed in the processing yard, they are transported to the construction site by trailers; railings or other obstacles are set up on both sides of the trailer to protect the steel pipe piles, and cables are used to tighten them to prevent them from falling; the piles should be stacked with multiple pads, and the pads should be placed evenly, and the top surfaces of the pads should be on the same plane; the steel pipe piles should be kept stable during stacking, transportation and lifting to avoid deformation of the steel pipe piles; ②Steel pipe pile extension The trailer transports the pile to the crawler crane, lifts the pile with the crawler crane hook, puts it into the pile driving frame and holds it tightly, and uses a special clamp to lift the steel pipe pile; the steel pipe pile is extended by full butt welding, and the weld is required to be full; when extending the steel pipe pile, the crawler crane lifts the steel pipe pile to be connected into place, and the construction workers take a small boat to carry out welding construction.

4. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1 is characterized in that: Step five specifically includes: installing the guide frame for driving the steel pipe pile in place according to the center plane coordinates of the steel pipe pile calculated before construction; after the steel pipe pile is positioned, using a crawler crane and a vibratory hammer for construction.

5. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1 is characterized in that: Step six specifically includes: after the steel pipe piles are driven, the construction of flat joints and scissor braces begins; the flat joints and scissor braces are connected by welding with channel steel; first, the channel steel is hoisted to the top of the pile by a crawler crane, and then it is slowly hoisted to the designed position for welding under manual command. During the construction process, the welding quality must be guaranteed to ensure the use function of the flat joints and scissor braces; Starting from the first section, the bridge deck height of the second section is 5.5m-8.2m, the bridge deck height of the third section is 8.2m-9.46m, the bridge deck height of the fourth section is 9.46m-12.22m, and the bridge deck height of the fifth section is 12.22m-14m.

6. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1, characterized in that: Step seven specifically includes: after verifying and confirming that the pile top elevation is correct, the I-beam load-bearing beam is hoisted to the top of the steel pipe pile (inside the slot) by a crane, the beam is placed in the center of the steel pipe pile according to the design and adjusted to the level, and welded after passing the inspection.

7. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1, characterized in that: Step eight specifically includes: before erection, the Bailey beam or I-beam is processed in advance to the corresponding length according to the drawings; before erection, the surveyor uses a total station to restore the pile axis according to the design drawings and marks it on the top plate of the head; the installer installs the Bailey frame or I-beam according to the measured axis, and the longitudinal center axis coincides with the axis of the steel pipe pile.

8. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1, characterized in that: Step nine specifically includes:

1. After the Bailey beams of the main trestle and the branch trestle are installed for one span, I22a I-beams are laid on the Bailey beams with a spacing of 75 cm as transverse distribution beams. After the laying is completed, the Bailey beams and the distribution beams are connected by fixed clamps, and one is set every 2.0 meters according to the width of the panel, and connected by steel plates for welding; 2. After the Bailey beam of the piling platform is installed for one span, I22a is installed on the Bailey beam with a spacing of 30cm; one is set every 2.0 meters according to the width of the panel and welded with connecting steel plates.

9. The construction method of a typhoon-resistant sea-crossing steel trestle and platform adjacent to residential buildings according to claim 1, characterized in that: Step 10 specifically includes:

1. After the installation of the I-beam distribution beam of the main trestle bridge is completed, a special bridge deck with a length of 6.0m×width of 2.0m×height of 0.15m is laid. The special bridge deck is welded on the I-beam and welded with bridge deck connecting steel plates. The weld length is 15cm and the width is 10cm to prevent the steel plate from curling back due to heavy vehicles.

2. Pile driving platform: After the I-beam distribution beam is paved, the full length 6.0m × width 2.0m × height 0.01m patterned steel plate is used as the bridge deck, and the bridge deck is welded to the I-beam; 3. Use channel steel as the bridge deck near the revetment; add cables or struts at the first and third stone steps to connect the pier and the steel trestle; add cables or struts at the fourth and fifth joints; Cable pulling method: find reefs to drill holes, plant steel bars, and use steel cables to connect the trestle to the reefs according to the actual situation on site; Support rod method: when the soil is shallow and there is no pulling point near the edge, support is used. The support material is steel or pipe. The model is determined according to the actual length. The excavator is used to tilt the soil and the upper end is welded to the side of the trestle. Installation of handrails: After the panel is laid, welding of safety handrails on both sides shall be carried out in time; 1.2m high handrails are set on both sides of the bridge deck, handrail columns are made of I14 I-beams with a spacing of 2m, and handrails are arranged in three rows of A48×3mm steel pipes; handrails of the trestle are painted with yellow and black magnetic paint for warning; for the safety of vehicles and pedestrians, an 18cm high skirting board is set on the inner side of the handrail along the longitudinal direction of the bridge, and the material is a 3mm thick steel plate.

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