Flow construction method for forming cast-in-place bored pile for gravel-decomposed rock stratum in double-machine combined mode

Abstract

The invention discloses a flow construction method for forming a cast-in-place bored pile for a gravel-decomposed rock stratum in a double-machine combined mode. The flow construction method comprises the steps that a high-power hydraulic spiral drilling machine is adopted to conduct drilling; drilling is conducted to the design pile bottom elevation; the requirements of a design and related specifications for the length of the pile and a bearing course at the pile end are met; pore-forming is finished; a drilling rod is lifted out; residue soil produced by pore-forming with the high-power hydraulic spiral drilling machine is layered again and poured in a pile hole through equipment such as an excavator, the speed rate of backfill is controlled, and the filling quality of backfill soil to the pile hole is guaranteed; after a pile position is rechecked and set out again, a long spiral drilling machine is adopted to conduct drilling again on the backfill hole position and pile body concrete is pumped into the pile hole through the end of a drilling rod of the long spiral drilling machine; the pouring top face of the pile body concrete is 0.5-1 m higher than the design pile top elevation; after pumping is finished, a reinforcement cage is lowered to the design elevation trough the method that after vibrating, the reinforcement cage is inserted into the pile body concrete; and the steps are repeated, so that pile-forming flow construction is realized through the combination of the high-power hydraulic spiral drilling machine and the long spiral drilling machine.

Description

technical field [0001] The invention relates to a pile-forming construction method of bored piles in construction engineering, and belongs to the technical field of construction. Background technique [0002] With the increasing shortage of planned land and the increasing load of building functions, the application of deep foundations is becoming more and more extensive. The bored pile is the main component of the deep foundation force transmission and deformation control structure, and the pile quality of the bored pile directly determines the safety and durability of the load-bearing structure of the building. [0003] The existing bored pile forming technology often adopts the method of single drilling rig forming pile. Rotary drilling rigs have fast hole formation and strong rock-breaking ability, but the construction noise is large, and the formation is greatly disturbed during drilling, and holes that are easy to collapse are drilled in pebbles and gravel layers; posi...

AI Technical Summary

Problems solved by technology

Rotary drilling rigs have fast hole formation and strong rock-breaking ability, but the construction noise is large, and the formation is greatly disturbed during drilling, and holes that are easy to collapse are drilled in pebbles and gravel layers; positive circulation and reverse circulation drilling rigs use mud protection to maintain pile holes. wall integrity, but the hole formation rate is low, there are problems such as mud discharge is easy to pollute the environment, and the existence of mud in the hole can easily lead to bedrock softening; it is difficult for long auger drilling rigs to break rocks in rock formations; , The drilling rate is higher in relatively complete strata, the disturbance to the stratum is small, the hole quality is high in the gravel layer, and the construction noise is low, but when the drill pipe of the high-power hydraulic auger drill is used to pump the pile body concrete in the hole, it often occurs. Due to the scheduling of concrete transport vehicles, traffic congestion and other problems, the pile-forming time is prolonged and the piling efficiency is reduced, and the rent of high-power hydraulic auger drilling rigs is high, and the economic benefit of using high-power hydraulic auger drilling rigs for single-machine piling is poor