Bored pile foundation bearing stratum reinforcing and strengthening construction method

Abstract

The invention relates to a bored pile foundation bearing stratum reinforcing and strengthening construction method. The bored pile foundation bearing stratum reinforcing and strengthening constructionmethod comprises the following steps that step one, grouting holes are drilled; step two, the grouting holes are cleaned; step three, grouts are prepared; step four, grouting is carried out; and stepfive, grouting hole openings are closed. Hole flushing carried out by adopting double-pipe high-pressure jet grouting is a key strengthening process, through high-pressure water flushing and cutting,soil in sediments, argillaceous contents in pile body separation segments and argillaceous contents in pile bottom fragmental intense weathering and weak intercalated layers can be flushed clean, andthe groutability of the grouts and the quality of induration are further improved, so that the bearing capacity of a sediment segment, pile bottom rock stratum fragments and weak intercalated layersis further improved; and in the grouting process, floral tubes are inserted into the grouting holes in a mode of floral tube grouting after rotary jet grouting is completed, and the problem that in the grouting hole forming, the pile tip soil body strength is reduced due to disturbance of soil around piles and the problem that water softening by soaking exacerbates the pile tip soil body strengthto be reduced during grouting hole cleaning are solved.

Description

technical field [0001] The invention relates to the technical field of pile foundation reinforcement, in particular to a construction method for reinforcing and strengthening the bearing layer of bored pile foundations. Background technique [0002] With the construction of a large number of high-rise and super-high-rise buildings, large-diameter cast-in-place piles, especially bored piles, have the advantages of high bearing capacity, no soil compaction, no vibration, construction close to existing buildings, and strong adaptability. It has been widely used in pile foundation engineering. However, quality accidents of large-diameter cast-in-place piles often occur, seriously affecting the performance of their bearing capacity. The pile end grouting method developed in recent years to deal with pile foundation quality accidents can not only improve the bearing capacity of large-diameter cast-in-situ piles, but also ensure stable and reliable quality when the design is reaso...

AI Technical Summary

Problems solved by technology

This reinforcement method is simple, economical, and highly operable. However, since the drilled (punched) holes are poured into piles as end-bearing piles, the bearing layer at the pile end is mostly complete bedrock with a dense structure, which makes it difficult for the grout to spread, resulting in a large reinforcement effect. discount

Images