Publication Abstract

Proceedings of the Deep Mixing 2015 Conference, (DFI)

Experiment to Determine the Influence of Groundwater Level on Grid-Form Deep Mixing Walls for Liquefaction Control
Masayuki Imai, Takenaka Civil Engineering & Construction Co. Ltd., Japan; Kazuo Konishi, Takenaka Civil Engineering & Construction Co. Ltd., Japan; Kunio Higashinaka, Takenaka Civil Engineering & Construction Co. Ltd., Japan; Tsuyoshi Honda, Takenaka Corporation, Japan; Kazuhiro Kaneda, Takenaka Corporation, Japan

In recent years, the demand for measures to control liquefaction of existing airport runways and harbor structures has increased. However, from the perspectives of constructability and cost, application of grid-form deep mixing walls to these types of structures requires the formation of wider grid spacing as compared with conventional designs. In this research, we focused on the extent of liquefaction and ground surface settling when grid spacing is made wider than conventional designs. We conducted centrifuge model tests, and confirmed the liquefaction suppression effect when grid-form modifications involving wide grid spacing are adopted under asphalt pavement. The tests were conducted under conditions that included changing the grid spacing and groundwater level. When the groundwater level was high, an increase in water pressure was observed, even within the grid. However, when the groundwater level was low, the increase in water pressure inside the grid was suppressed. We also found that if the generation of water pressure can be suppressed, the amount of settling due to liquefaction can also be controlled.

 article #2056; publication #1013 (DM-2015)