Geomembrane containment walls for liquefaction remediation

Abstract

Ground improvement techniques can be adopted to prevent existing buildings built on liquefiable soils sustaining damage in future earthquakes. Impermeable geomembrane containment walls may be an economic and successful technique but their design and performance are currently not well defined or well understood for this application. This paper describes centrifuge testing carried out to investigate the performance of such containment walls as a liquefaction remediation method for a single degree of freedom frame structure. The results were compared with those from similar centrifuge testing carried out with the same structure founded on unimproved sand, to assess the effectiveness of the remediation method. It was found that the geomembrane containment walls tested were effective at reducing structural settlement and did not significantly increase the accelerations transmitted to the structure. Structural settlements were reduced primarily by mobilising hoop stress and preventing lateral soil movement. By preventing surface drainage, a decrease in the volume change of the foundation sand was also observed. In addition, the impermeability of the walls may be important as this prevented rapid migration of pore water from the free field to the foundation region.

The Dynamic Behaviour of Pile Foundations in Seismically Liquefiable Soils: Failure Mechanisms, Analysis, Re-Qualification

“…New techniques are introduced either to prevent liquefaction or to minimise the resulting settlements. Piled foundations of existing buildings are often difficult to access for retrofitting and, in addition, any procedure must ensure that the superstructure is not damaged during remediation [142]. Remediation of liquefiable soils for pile foundations needs to meet the several design performances required [143].…”

Editorial

“…The second paper by Mitrani and Madabhushi (2013) focuses on the mitigation of liquefaction of soils using high-density polyethylene geomembrane containment walls for residential structures. The paper describes extensive test results from centrifuge tests using these walls with a single degree of freedom frame structure.…”