Grouting molding pedestal pile and construction method thereof and pedestal expanding device

Abstract

The invention discloses a pedestal expanding device which comprises a geotechnical cloth bag and a grouting pipe, wherein the geotechnical cloth bag is sleeved on the outer side of the bottom of a steel reinforcement cage. The upper end and the lower end of the geotechnical cloth bag are fixed with the bottom of the steel reinforcement cage. The middle portion of the geotechnical cloth bag is tightened by a plurality of elastic bands, and one end of the grouting pipe is inserted into the geotechnical cloth bag. The invention further discloses a grouting molding pedestal pile and a construction method thereof. The method includes the steps of setting the pedestal expanding device on the outer side of the bottom of the steel reinforcement cage, and placing downward the steel reinforcement cage provided with the pedestal expanding device at the bottom in place, and pouring concrete into the steel reinforcement cage, and beginning to grout after the maintenance of the concrete. The geotechnical cloth bag of the pedestal expanding device forms a plump cylindrical grouting bag structural body under the filling of cement paste, the diameter of the geotechnical cloth bag swells continuously along with the injection of the cement paste liquid and is expanded, then the geotechnical cloth bag can squeeze the concrete around and enables the soil body around to be dense, and finally a pile end expanding head is formed, so occlusion capacity of pile soil and bearing capacity of the pile can be greatly improved.

Description

technical field [0001] The invention relates to the field of building construction, and relates to a bottom-expanding construction method and a bottom-expanding device suitable for bored piles. Background technique [0002] The existing post-grouting technology is to bury high-pressure grouting hoses on the reinforcement cages at different depths on the pile side, and after the bored piles are poured with concrete, the cement mortar is injected into the soil layer on the pile side through the pre-buried pipes. A technique to increase pile side friction. According to the results of some experiments, it is believed that post-grouting treatment can achieve better results, and the bearing capacity of single piles in fine-grained soils can be increased by 30% to 70%; for piles in coarse-grained soils, the increase can reach 60%. ~120%. The side friction effect after grouting is manifested as the increase of side friction resistance and the shear stiffness of pile side soil; thu...

AI Technical Summary

Problems solved by technology

It can be seen that in this technical solution, a steel pipe is needed, and the steel pipe needs to be welded on the bottom of the steel cage first, and then the geotextile bag is placed on the outside of the steel pipe, the structure is more complicated, and the construction process is more cumbersome.

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