Method for forming pile foundation in karst area

Abstract

The invention provides a pile forming method for a pile foundation in a karst area. The method comprises the steps that the positions and the number of karst caves are comprehensively determined according to advanced drilling, pipe wave detection and the drilling process of a rotary drilling machine; in the drilling process of the rotary drilling machine, a special drill bit is used at the position of the karst cave to press pile core soil and gravel into the karst cave, and the compactness of filler in the karst cave is increased; a thickened double-layer reinforced composite membrane is installed outside a reinforcement cage according to data of the specific position of a karst cave, then the reinforcement cage is hoisted into a pile hole, a composite bag is filled with concrete before grouting so that the concrete can block the karst cave, and grouting is conducted after the concrete in the composite membrane reaches certain strength to form a pile foundation. The construction difficulty of a pile foundation in a karst area can be reduced, the defect that semi-filling and non-filling type karst caves are prone to hole collapse is overcome, the later-period karst cave processing procedure is reduced, the problem of slurry leakage in the pile body grouting process is solved, and the composite membrane is low in manufacturing cost and convenient to use.

Description

technical field [0001] The invention relates to pile foundation engineering in the field of construction engineering in karst areas, in particular to a pile-forming method for pile foundations in karst areas. Background technique [0002] There are many fissures in the rock mass in nature, and groundwater often flows along these fissures, eroding and eroding the rocks, making the fissures gradually expand and forming small caves. For soluble rocks such as limestone, dolomite, and marl, their special properties provide potential favorable conditions for the formation of karst caves, and larger karst caves are easy to form. The geological conditions in karst areas are complex, and there are randomly distributed caves of different sizes in the rock mass. The pile foundation needs to pass through the caves and enter the intact rock, which provides a lot of difficulty for the pile foundation to determine the specific depth of the bearing layer. Existence, grout leakage is easy t...

AI Technical Summary

Problems solved by technology

[0004] Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide a method for forming pile foundations in karst areas, so as to solve the construction problems existing in the prior art The problem of long cycle and high cost

Images