Construction method of deep-hole high-pressure jet grouting pile in gravel soil layer

Abstract

The invention provides a construction method of a deep-hole high-pressure jet grouting pile in a gravel soil layer, and belongs to the field of civil engineering. The construction method solves the problem that the deviation of the drilling perpendicularity in the deep gravel soil layer with large particle size difference is large, reduces the drilling depth deviation of a geological drilling machine in the gravel soil layer, and plays a beneficial role in increasing the effective lap joint range of the bottom of the jet grouting pile. A double-hole nozzle which is separated up and down is adopted, so that the replacement and diffusion capacity of slurry in gravel soil filler is improved, a cemented pile body with gravel wrapped by cement slurry is formed, and the effects of preventing seepage and improving the strength are achieved. According to the construction method, the drilling perpendicularity control and the jet grouting pile construction method are combined, so that effectivelap joint of the high-pressure jet grouting pile in 50 m deep portion of the gravel soil layer having the large particle size difference can be realized. Experience is provided for seepage preventiontreatment and foundation treatment construction under similar lithological conditions in the future, and the construction method is suitable for treatment and seepage prevention engineering such as foundation reinforcement and water interception curtains.

Description

technical field [0001] The invention relates to the technical field of civil engineering, in particular to a construction method for deep-hole high-pressure rotary grouting piles in gravel soil layers. Background technique [0002] High-pressure rotary grouting piles are generally suitable for foundation treatment, water-stop curtain, dam anti-seepage reinforcement and other projects of flow-plastic-plastic cohesive soil, silt, sandy soil, plain fill soil and gravel soil. The stratum in which pebbles, boulders and boulders in rock and gravel soil form a skeleton structure shall be used after determining its feasibility. When carrying out high-pressure jet grouting pile construction in areas with deep gravel soil layers, geological drilling rigs are generally used to guide holes. When the pilot hole is a deep hole with a depth greater than 30 meters, the inclination value of the lower half of the borehole is likely to exceed the effective radius of the jet grouting pile, maki...

AI Technical Summary

Problems solved by technology

When carrying out high-pressure jet grouting pile construction in areas with deep gravel soil layers, geological drilling rigs are generally used to guide holes. When the pilot hole is a deep hole with a depth greater than 30 meters, the inclination value of the lower half of the borehole is likely to exceed the effective radius of the jet grouting pile, making The failure of the curtain due to the imperfect lapping of the adjacent piles

Because the gravel in the gravel soil layer has a blocking effect on the high-pressure jet flow, the pile-forming effect of the high-pressure rotary grouting pile is affected by conditions such as the ability of the slurry to cut the filling, the particle size of the gravel, and the diffusivity of the slurry, resulting in a large diameter of the pile. Uncertainty, it is easy to make the adjacent piles unable to overlap, resulting in curtain leakage problems. If there is a situation where the hole is too large and the diameter of the pile is small, the quality and effect of the curtain will not be guaranteed