Dry sandy gravel stratum cast-in-place pile construction method

Abstract

The invention discloses a construction method for a cast-in-place pile in a dry sandy gravel stratum. The construction method comprises the following steps that a site is leveled; a long spiral drilling machine is adopted for pre-forming holes, and cement paste is poured in a pressing mode; the method is suitable for the technical field of pile foundation hole forming, effectively combines the advantages of a long spiral and a drilling rig, effectively solves the problem of hole collapse, avoids the influence of mud cake on pile side friction resistance, improves the pile foundation bearing capacity, improves the pile foundation construction quality, reduces the construction cost and improves the construction efficiency. And the construction cost is effectively reduced.

Description

technical field [0001] The invention belongs to the technical field of pile foundation hole forming, in particular to a construction method of a cast-in-place pile in dry sand and pebble stratum. Background technique [0002] The problems of hole formation and quality assurance of cast-in-place piles in sand and pebble layers without groundwater within the construction scope have not been well solved by traditional construction techniques. If the hole is formed by rotary drilling and impact drilling, mud wall protection is required. The wall protection effect is unsatisfactory due to serious leakage of slurry. ; Long screw dry operation will not produce mud skin and collapsed holes, but it is difficult to form holes, and because the cement slurry in the concrete in the dry sand and pebble layer is lost too quickly, the workability is rapidly reduced. , the steel cage is difficult to put in place, and the construction quality cannot be guaranteed. [0003] There are two mai...

AI Technical Summary

Problems solved by technology

[0004] The construction technology of inserting steel cage after long screw press concrete has the following disadvantages: in the dry sandy pebble formation, the cement slurry in the concrete is absorbed by the dry sandy pebbles around the pile, and the workability of the concrete is reduced, resulting in the subsequent reverse insertion The steel cage is lower than the design elevation, seriously affecting the construction quality of the pile foundation

[0005] There are the following disadvantages in the underwater pouring construction technology of rotary excavation and mud retaining wall: 1. The mud retaining wall is used to form a mud skin and reduce the frictional resistance on the pile side

2. Can not effectively solve the sediment at the bottom of the hole, affecting the bearing capacity of the pile end

3. It cannot effectively solve the problem of hole collapse in dry sand and pebble formations, resulting in oversquare concrete and increasing construction costs

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