1. Construction requirements for steel pipe piles
During the construction of high-speed railway bridges, steel pipe piles are the main part of the bridge support system, and their construction technology has a direct impact on the bridge's support capacity. Steel pipes(such as welded steel tube and seamless pipe) are the main materials used in construction. The actual selection standards of steel pipes should be determined according to the construction design requirements and clearly stated in the construction plan. The quality of steel pipe materials is mainly affected by the material, thickness, and thickness.
Although the piling pipe foundation construction only exists as a temporary facility, the process flow should not be ignored. Its construction quality has a greater impact on the quality of the bridge supports and the personal safety of the construction personnel. The selection of the steel pipe pile foundation construction method needs to be finalized according to the actual conditions of the construction site. The crawler crane clamp hydraulic vibration hammer pile sinking method is widely used on bridges with narrow width. The implementation process of this method is to make the steel pipe Complete settlement root by root.
2. Steel pipe pile foundation construction
Before the official start of construction, it is necessary to carefully survey the foundation conditions around the steel pipe piles, especially the detailed conditions of the foundation where the pier columns are located, and keep records. If the bridge cap is soaked by rainwater, it will have a great impact on the bearing capacity of the foundation. If the impact is large, special treatment of the foundation is required.
The construction personnel must mark the precise position of the piling according to the requirements of the design drawings, and use the total station to achieve precise alignment of the steel pipe and piling coordinates. After the vibrating hammer clamps the steel pipe, it relies on its own gravity to insert it into the piling position, and then Use a vibrating hammer to apply pressure to the steel pipe to cause it to sink. The sinking depth must be consistent with the design standard. According to this plan, the settlement of each steel pipe is completed.
3. Precautions for construction of steel pipe pile foundation
The technical facilities of steel pipe piles only exist as temporary facilities in the entire bridge construction project. After the construction of the cast-in-place beam supports is completed, they must be dismantled and will not have any load-bearing function after the bridge is put into use. Therefore, the steel pipe piles The construction link is often ignored during the construction of cast-in-place beam supports, resulting in deficiencies in the entire construction process and insufficient consideration of the quality and performance of construction materials. During actual construction, the following contents must be grasped.
(1) When welding steel pipe piles, the quality of the welds must be strictly inspected to ensure that there are no quality problems in the welding joints between steel pipes to avoid any impact on the bearing capacity of the steel pipe pile foundation due to welding quality problems and the impact on the steel pipe piles. Ultrasonic testing can usually be used to detect weld quality.
(2) It is necessary to analyze the actual load-bearing capacity of the steel pipe pile based on the actual application situation, and then determine whether its load-bearing capacity meets the design requirements. Select the steel pipe with the largest offset or the largest inclination for test analysis. The test results are consistent with the design requirements. The load-bearing capacity can be said to meet the design requirements only when the experimental value is higher than the design value.
During the construction of high-speed railway bridges, steel pipe piles are the main part of the bridge support system, and their construction technology has a direct impact on the bridge's support capacity. Steel pipes(such as welded steel tube and seamless pipe) are the main materials used in construction. The actual selection standards of steel pipes should be determined according to the construction design requirements and clearly stated in the construction plan. The quality of steel pipe materials is mainly affected by the material, thickness, and thickness.
Although the piling pipe foundation construction only exists as a temporary facility, the process flow should not be ignored. Its construction quality has a greater impact on the quality of the bridge supports and the personal safety of the construction personnel. The selection of the steel pipe pile foundation construction method needs to be finalized according to the actual conditions of the construction site. The crawler crane clamp hydraulic vibration hammer pile sinking method is widely used on bridges with narrow width. The implementation process of this method is to make the steel pipe Complete settlement root by root.
2. Steel pipe pile foundation construction
Before the official start of construction, it is necessary to carefully survey the foundation conditions around the steel pipe piles, especially the detailed conditions of the foundation where the pier columns are located, and keep records. If the bridge cap is soaked by rainwater, it will have a great impact on the bearing capacity of the foundation. If the impact is large, special treatment of the foundation is required.
The construction personnel must mark the precise position of the piling according to the requirements of the design drawings, and use the total station to achieve precise alignment of the steel pipe and piling coordinates. After the vibrating hammer clamps the steel pipe, it relies on its own gravity to insert it into the piling position, and then Use a vibrating hammer to apply pressure to the steel pipe to cause it to sink. The sinking depth must be consistent with the design standard. According to this plan, the settlement of each steel pipe is completed.
3. Precautions for construction of steel pipe pile foundation
The technical facilities of steel pipe piles only exist as temporary facilities in the entire bridge construction project. After the construction of the cast-in-place beam supports is completed, they must be dismantled and will not have any load-bearing function after the bridge is put into use. Therefore, the steel pipe piles The construction link is often ignored during the construction of cast-in-place beam supports, resulting in deficiencies in the entire construction process and insufficient consideration of the quality and performance of construction materials. During actual construction, the following contents must be grasped.
(1) When welding steel pipe piles, the quality of the welds must be strictly inspected to ensure that there are no quality problems in the welding joints between steel pipes to avoid any impact on the bearing capacity of the steel pipe pile foundation due to welding quality problems and the impact on the steel pipe piles. Ultrasonic testing can usually be used to detect weld quality.
(2) It is necessary to analyze the actual load-bearing capacity of the steel pipe pile based on the actual application situation, and then determine whether its load-bearing capacity meets the design requirements. Select the steel pipe with the largest offset or the largest inclination for test analysis. The test results are consistent with the design requirements. The load-bearing capacity can be said to meet the design requirements only when the experimental value is higher than the design value.
