Views:5 Author:Site Editor Publish Time: 2021-12-28 Origin:Site
The purpose of steel pipe pile construction is to transfer the load of the upper building to the deep soil layer with strong bearing capacity or to compact the soft soil layer to improve the bearing capacity and compactness of the foundation soil. Therefore, the steel pipe pile must be ensured The quality of the construction, otherwise, the building will be unstable.
The steel pipe pile construction steps are:
1. Measure and pay off. The surveying engineer stakes out according to the designed pile position map and marks the piling point with wooden stakes or white ash.
2. The piling machine is in place. The pile driver is in place, aligned with the pile position, and the construction is carried out vertically and stably to ensure that it does not tilt or move during the construction. The pile driver is placed on the pile position, the steel pipe pile is hoisted into the pile driver, and then the pile end is positioned at the center of the pole position, the mast is raised, and the level and the pile core are being corrected.
3. Welded pile tip. Take the commonly used cross pile tip as an example. The cross pile tip is placed at the post-checked pile position, and the bottom endplate of the single-section steel pipe pile is welded together with its centering. The welding adopts CO2 protective welding, and the pile tip adopts anti-corrosion after welding. Asphalt painting.
4. Verticality detection. Adjust the extension length of the oil plug rod of the outrigger cylinder of the pile machine to ensure that the pile machine platform is level. After the pile is 500mm into the soil, use two theodolites to measure the verticality of the pile in a vertical direction. The error should not exceed 0.5%.
5. Pile pressing. The concrete strength of the pile reaches 100% of the design strength, and the pile can be pressed only when the pile is kept vertical under the verification of the two theodolites. If the pile body is severely cracked, tilted, suddenly shifted, and penetrated when the pile is pressed Sudden changes and other phenomena should stop construction, and proceed after handling. Pay attention to the speed of pressing the pile when pressing the pile. When the pressing pile enters the sandy soil layer, the pressing speed should be appropriately increased to ensure that the pile tip has a certain penetration ability. When it reaches the bearing layer or the oil pressure suddenly increases, it should Slow down the press-in speed to prevent broken piles.
6. Connect piles. Generally, the length of a single-section steel pipe pile does not exceed 15m. If the design pile length is greater than the length of a single-section pile, the pile needs to be connected. Generally, the electric welding process is used to weld the pile. Continuous and full, without construction defects. After the pile connection is completed, it is necessary to pass the acceptance before proceeding with the piling construction.
7. Send piles. When the pile is pressed to 500mm away from the filling surface, use the pile feeder to press the pile to the design elevation, and appropriately increase the static pressure. Before the pile is sent, the pile depth should be calculated according to the design requirements, and the pile feeder should be the eye-catching mark. When the piles are delivered to about 1m away from the design elevation, the surveying personnel instructs the pile machine operator to reduce the pile pressing speed, and track the pile delivery situation, until the piles are delivered to the design elevation, a signal is sent to stop the pile delivery.
8. Final pile. During the construction of the engineering pile, the pressure value and pile length are required to be dual-controlled. Entering the bearing layer is mainly controlled by pile length and supplemented by pressure value control. If there is an abnormality, the design unit shall be notified for handling.
After mastering the construction steps of the steel pipe piles above, I believe that the service life of our steel pipe piles will be longer than expected