Karst cave treatment method applied to karst area cast-in-situ bored pile construction

Abstract

The invention relates to a treatment method of karst caves with different sizes and types applied to karst area cast-in-situ bored pile construction. Firstly, the depths and the heights of the karst caves at pile positions are obtained by adopting an advance drilling technology; treatment is conducted on non-filled karst caves and semi-filled karst caves with the cave heights being higher than 3 mby adopting a concrete pouring method; treatment is conducted on non-filled karst caves and semi-filled karst caves with the cave heights being between 1.5 m and 3 m by adopting a mortar pouring method; treatment is conducted on non-filled karst caves with the cave heights being between 0.5 m and 1.5 m and semi-filled karst caves with the cave heights being between 1 m and 1.5 m by adopting a screen pipe grouting method; and treatment is conducted on non-filled karst caves with the cave heights being lower than 0.5 m and semi-filled karst caves and full-filled karst caves with the cave heights being lower than 1 m by adopting a sleeve valve pipe grouting method. The karst cave treatment method can conduct treatment on the different types of karst caves well.

Description

technical field [0001] The invention relates to the technical field of karst cave treatment in bored piles, in particular to a method for treating karst caves of different sizes and types used in the construction of bored piles in karst areas. Background technique [0002] When constructing in karst areas, the existing technology often adopts the method of backfilling concrete in karst caves and then drilling (such as Chinese patent 201410376534.4). This method consumes and wastes serious concrete, and it is difficult to control the initial setting and drilling time of concrete. Drilling is difficult after the strength of concrete increases. [0003] The bored pile is currently the most widely used type of pile foundation. It has a high degree of mechanization, a large single pile bearing capacity, and strong rigidity of the pile body. When constructing in karst areas, pile holes often need to pass through karst caves, which may easily cause grout leakage, necking and hole ...

AI Technical Summary

Problems solved by technology

When constructing in karst areas, pile holes often need to pass through karst caves, which may easily cause grout leakage, necking and hole collapse during the hole forming process. When pouring concrete, a large amount of concrete will pour in from the connection between the pile holes and karst caves and Filling the karst caves results in a large amount of concrete overfilling and a high filling coefficient, which leads to higher project costs

In the prior art, a single throw-fill method is usually used to deal with different types of karst caves, but in fact, due to the complex geological conditions of karst caves, the traditional methods have very different treatment effects for different types of karst caves

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