Construction method for lightweight columns used in ground improvement

The described method for soilless drilling with filling materials and pressure insertion stabilizes lightweight columns below groundwater, addressing floatation issues and reducing complexity and cost in ground improvement.

JP2026086274APending Publication Date: 2026-05-26TOBISHIMA CONSTRUCT
View PDF 2 Cites 0 Cited by

Patent Information

Authority / Receiving Office
JP Β· JP
Patent Type
Applications
Current Assignee / Owner
TOBISHIMA CONSTRUCT
Filing Date
2024-11-14
Publication Date
2026-05-26

AI Technical Summary

Technical Problem

Existing methods struggle to stably bury lightweight columns, such as wooden columns, in the ground below groundwater level without causing them to float, and often require complex equipment and high construction costs.

Method used

A construction method involving an insertion pipe for soilless drilling, where upper and lower filling materials are placed inside a drilling pipe with lightweight columns, and the pipe is inserted while applying pressure, followed by increasing internal pressure and withdrawing the pipe to secure the columns in place.

Benefits of technology

This method allows for stable burial of lightweight columns, even below groundwater, without direct contact with the ground, reducing damage and enabling large-diameter columns to be installed at great depths, while minimizing equipment complexity and cost.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 2026086274000001_ABST
    Figure 2026086274000001_ABST
Patent Text Reader

Abstract

This invention provides a construction method for lightweight columns used in ground improvement, which allows for the stable burial of lightweight columns, even those that tend to float on water, into the ground. [Solution] The construction method for a lightweight column used for ground improvement according to the present invention comprises the steps of: constructing an insertion pipe for soilless drilling by filling an upper filling material, a lightweight column, and a lower filling material into a drilling pipe in the order of upper filling material, lightweight column, and lower filling material from top to bottom; inserting the insertion pipe for soilless drilling into the ground without soil removal while applying pressure inside the insertion pipe for soilless drilling; and after inserting to a predetermined depth, increasing the pressure inside the insertion pipe and then pulling out only the drilling pipe while rotating it, wherein both the upper filling material and the lower filling material are composed of sand or crushed stone.
Need to check novelty before this filing date? Find Prior Art