Small-diameter micro static-pressure steel pipe pile post-grouting construction method

Abstract

The invention discloses a small-diameter micro static-pressure steel pipe pile post-grouting construction method. The method comprises the specific procedures of small-diameter steel pipe pile manufacturing, pile pressing, steel pipe inner wall cleaning, gravity grouting, pressure grouting, static curing and concrete casting. In the micro static-pressure steel pipe pile post-grouting construction method, firstly, a small-diameter steel pipe is pressed into a soil layer; after the inner wall of the steel pipe is cleaned by using the water pressure, a finish-rolled thread reinforcement is put into the steel pipe pile, and grouting is performed, so that the small-diameter steel pipe is low in pile pressing resistance and pile body stress, is not obvious in soil extrusion effect, guarantees the perpendicularity, and is high in construction efficiency and low in comprehensive cost; and in addition, as the finish-rolled thread reinforcement is additionally arranged in the steel pipe, on the one hand, the drawing resistance of the reinforcement is used, and on the other hand, subsequent connection with a foundation is convenient. Meanwhile, a staging post-grouting method is adopted to improve a mixing effect between cement paste and soil around a pile foundation so as to prominently improve the bearing performance.

Description

technical field [0001] The invention relates to the technical field of micro-steel pipe pile foundation construction, in particular to a post-grouting construction method for small-diameter micro static-pressure steel pipe piles. Background technique [0002] Micro steel pipe pile foundation refers to the steel pipe pile foundation with a diameter of no more than 300mm and a ratio of pile length to pile diameter of no less than 30. It is mostly used in reinforcement and renovation projects of buildings, bridges, and transmission line equipment foundations. At present, there are four main construction methods for micro-steel pipe pile foundations: hammering type, auger drilling type, static pressure type and pre-drilled hole embedding type. The hammering type refers to the construction method of driving steel pipe piles into the soil layer; the auger drilling type refers to the construction method of pressing the steel pipe piles with threads on the pile body into the soil la...

AI Technical Summary

Problems solved by technology

The static pressure type needs to be able to provide the pile pressure reaction device on site. The pile pressure efficiency is low when the pile body is long or the pile diameter is large, and the large pile diameter will produce obvious soil squeezing effect, which will adversely affect the surrounding pipelines or adjacent buildings.

The pre-drilled embedded type needs to be drilled first and then placed in the steel pipe pile. When the soil condition is poor, the hole is prone to collapse and affect the quality of subsequent grouting. In addition, a large amount of mud will be discharged at the same time, causing environmental pollution. higher total cost