Preparation method of post-grouting reinforced CFG pile with anti-break pile head

Abstract

The invention belongs to the field of piling and specifically relates to a preparation method of a post-grouting reinforced CFG pile with an anti-break pile head. The method is characterized by comprising the steps that firstly, drilling is carried out with a spiral drilling machine; secondly, after drilling construction to a hole bottom and pressure grouting of concrete to a pile top, a first reinforcing bar (6) is inserted into the pipe top with a depth of 0.5m-1m, so a precast CFG pile is formed; thirdly, a back insertion steel tube (2) with a grouting head is inserted to a pile end from the center of the pile top of the precast CFG pile, and a steel strand (5) extends to the front end of the back insertion steel tube (2) from the rear end of the rear insertion steel tube (2); fourthly,after shaping of the precast CFG pile for 24h-48h, gradually grouting is conducted in the back insertion steel tube(2) by the grouting head, and the pile end is reinforced; fifthly, lengths of the first reinforcing bar (6) and the steel strand (5) exposed above the pile top are trimmed; sixthly, a sandy stone filling layer is poured on the first reinforcing bar (6) and the steel strand (5) abovethe pile top; and seventhly, roadbed building stones are disposed on the sandy stone filling layer and then compacted. The preparation method provided by the invention has the beneficial effects thatthe pile end is firm, and the pipe top is firm and free of getting broken.

Description

technical field [0001] The invention belongs to the field of piling, and in particular relates to a method for preparing a post-grouting reinforced CFG pile of an anti-breaking pile head. Background technique [0002] In the prior art, when the pile tip is located in silt or silty clay, the bearing capacity and deformation cannot meet the requirements, or the bearing capacity meets the requirements, but the deformation cannot meet the requirements, and it is easy to penetrate into the damaged site. [0003] According to the requirements of the specification, when constructing CFG piles, a protective soil layer of 300mm-500mm is required above the top of the piles, and mechanical walking construction is carried out on the top of the piles, and it is ensured that the shallow parts of the tops of CFG piles will not be broken during excavation. However, in some areas, the soil quality at the top of the pile is relatively soft and poor, and the 500mm protective soil layer cannot ...

AI Technical Summary

Problems solved by technology

However, in some areas, the soil quality at the top of the pile is relatively soft and poor, and the 500mm protective soil layer cannot guarantee that the CFG pile will not break the shallow pile. The main reason is that the CFG pile is a plain concrete pile, and the plain concrete can withstand large compressive stress. , but it cannot withstand excessive shear stress. When the soil layer is too weak, the shear stress is too concentrated on the concrete at the shallow part of the CFG pile head, resulting in broken piles.

Previous experience is that either increasing the thickness of the protective layer or adding piles after the fact will cause a substantial increase in cost and delay in the construction period

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