A post-grouting reinforced cfg pile preparation method for anti-breaking pile head

Abstract

The invention belongs to the field of piling, and in particular relates to a method for preparing a post-grouting reinforced CFG pile for preventing pile heads, which is characterized in that it is carried out in accordance with the following steps: Step 1, drilling with an auger; Step 2, drilling to the hole After pouring concrete to the top of the pile, insert the first steel bar (6) into the top of the pile by 0.5m-1m to form a pre-CFG pile; Step 3, use a post-inserted steel pipe (2) with a grouting head from the pre-CFG The center of the CFG pile top is inserted to the pile end, and the steel strand (5) is extended from the rear end of the rear insertion steel pipe (2) to the front end of the rear insertion steel pipe (2); step 4, after the pre-CFG pile is formed for 24h‑48h, Step by step grouting in the steel pipe (2) through the grouting head pair, reinforce the pile end; step five, trim the length of the first steel bar (6) and the steel strand (5) exposed above the top of the pile; The first steel bar (6) and the steel strand (5) above the roof are poured with sand and gravel filling; Step 7, setting and compacting roadbed stones above the sand and gravel filling. The pile end of the present invention is fastened, and the pile top is solid and not 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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