Dynamic water environment three-pipe jet grouting pile in-pit construction method

Abstract

The invention discloses a dynamic water environment three-pipe jet grouting pile in-pit construction method. The method comprises the steps of construction preparation, pile position lofting, drainage ditch excavation, sewerage system building, drilling machine in-place, slurry preparation, drilling pipe insertion, jet grouting lifting, in-pit jet grouting pile construction, compaction grouting, well repairing and the like. According to the method, the construction equipment is simple, high in maneuverability and small in occupied area; the requirement for low-clear-height construction can be met, a machine conducts construction in the limited space from the pit bottom to an upper tunnel support, and movement of the machine on the excavated foundation soil surface is not hindered; the construction machine is small in vibration, low in noise, high in speed and convenient to operate; earth excavation and peripheral foundation structures can be carried out at the same time, and cross construction is achieved; and in the dynamic water environment, compared with a traditional double pipe method, the pile forming diameter and the consolidated stone rate are good in quality, and the construction efficiency is high.

Description

technical field [0001] The invention relates to a construction method in a rotary grouting pile pit. Background technique [0002] In the construction of deep foundation pits, in order to ensure the stability of the slope of the deep pit during the excavation of the ultra-deep area of ​​the foundation pit and to increase the weight of the soil at the bottom of the pit to balance the buoyancy generated by the confined water, high-pressure jet grouting piles are generally used for super-deep excavation. Reinforce the soil in the area and the surrounding area, so that the solidified soil and the engineering pile group are integrated. The conventional jet grouting pile technology first reinforces the bottom of the pit before the excavation of the earthwork or after excavating a part of the upper soil, and the groundwater level is relatively balanced and stable. . However, during the construction process, due to the sudden adjustment of the design plan, or the optimization of th...

AI Technical Summary

Problems solved by technology

Since the high-pressure rotary grouting piles are operated in the pit, the height limitation of the surrounding support and the dense engineering piles in the pit have a great influence on the mechanical construction. Under the influence of groundwater precipitation seepage (moving water), the traditional high-pressure jet grouting pile is greatly affected. Before the initial setting of the slurry, the groundwater seepage will dilute or even take away the jet grouting slurry, which cannot be effectively cemented, and it is difficult to ensure the jet jetting. The pile quality of the pile and the water-stop effect of the enclosure structure