What should we pay attention to when constructing steel pipe piles

The construction quality of steel pipe piles is related to the stability of the building, so some details must be paid attention to during the construction of steel pipe piles. The main precautions for steel pipe pile construction include:

1. Before the construction of steel pipe piles, it is necessary to measure and lay out the lines, which needs to be carried out by professional surveyors. After all axes and pile positions have been placed, construction can only start after being reviewed by the supervisor.

2. After the pile driver is in place, the pile frame should be adjusted first to ensure that the pile frame is vertical and stable.

3. For the steel pipe piles that are to be lifted and driven, first check whether the quality of the pile body meets the requirements of the specification, draw a length mark on the pile body in meters, and mark the length of the pile from bottom to top, to observe the depth of the pile into the soil. and record the number of hammer blows per meter of pile sinking.

4. After the steel pipe piles are aligned and in place, they should be straightened repeatedly on both sides with a wire drop. Try to make sure that the hammer, cap, and piles are all in the same straight line. It is strictly forbidden to drive them sideways.

5. During the driving process, if the pile body is deflected, the deviation cannot be forcibly corrected by machinery, nor should it be corrected while driving. The deflection should not be corrected within the scope allowed by the specification, to prevent the pile body from cracking; if the verticality deviation is found to be greater than the specification requirement, first find out the cause, pull out the pile section, and backfill the pile hole with sand. After that, hit the point again.

6. When the steel pipe pile needs to be extended and the pile head sinks to 500 mm-800 mm above the ground, the hammering can be stopped and the previous pile can be connected. When connecting piles, guide hoops (barge pile clamps) should be installed at the lower pile heads so that the upper piles should be in place. The upper and lower pile sections should be kept straight. Then remove the barge pile clamps and clean the upper and lower end plates with a wire brush. Perform welding.

7. When driving piles in thick sandy soil or silty clay layers, it is advisable to drive one pile continuously at one time until the hammer is hammered. Because when driving piles in this type of soil, the soil's consolidation force is strong. If you stop driving piles for some time, the piles will not be driven due to the consolidation effect of the soil and the recovery of the soil. If you drive them forcefully, problems will occur. The phenomenon of breaking the pile head.

8. When the steel pipe pile is driven to the bearing layer required by the design or reaches the penetration value required by the design, the hammer can be retracted. After the steel pipe pile is hammered, actual measurement records must be made in time, and the vertical deviation of the pile must be measured with a line drop, and the east, south, west, and north directions and their percentage values must be filled in truthfully; for suspected pile numbers, the vertical deviation must be measured accurately. Use a heavy hammer line or light to detect the hole and compare it with the length of the pile. If any problems are found, report them in time.

9. When the top of the pile is driven close to the ground and it is necessary to send the pile, the verticality of the pile should be measured and the quality of the pile top should be measured before sending the pile. The pile feeder should match the size of the steel pipe pile. Sacks or cardboard should be added as a cushion between the pile heads of the pipe piles. To ensure the single pile bearing capacity of the steel pipe piles, the penetration value of the piles should be tightened, which is generally 80% when the piles are not fed.