Liquefaction and Drainage in Stratified Soil

• Published in: Journal of geotechnical and geoenvironmental engineering Vol. 131; no. 7; pp. 876 - 885
• Main Authors: Brennan, A. J, Madabhushi, S. P
• Format: Journal Article
• Language: English
• Published: New York, NY American Society of Civil Engineers 01.07.2005
• Subjects: Applied sciences; Buildings. Public works; Exact sciences and technology; Geotechnics; Soil investigations. Testing; Soil mechanics. Rocks mechanics; TECHNICAL PAPERS; Centrifuge; Sand; Vertical drain; Liquefaction; Vertical drains; Layered soils; Drainage; Stratified medium; Experimental result; Soil test; Pore pressure; Remedial action; Behavior; Stratification
• ISSN: 1090-0241; 1943-5606
• DOI: 10.1061/(ASCE)1090-0241(2005)131:7(876)

Remediation schemes for the treatment of liquefiable ground, such as vertical drains, have evolved over the last 30 years largely as a result of consideration of uniform sand beds. However, many liquefiable sites also contain thin layers of silts and clays which will act as an obstacle to fluid dissipating from liquefying sands, such that the performance and requirements of a remediation scheme will be different. In particular, water films may be produced. This paper presents results from a series of dynamic centrifuge experiments on vertical drains in level liquefiable sand deposits. Centrifuge tests were conducted both with and without surface fine layers. The drains prevented sand boiling, and the thin surface fine layers did not significantly affect excess pore pressure response. A further centrifuge test on a thin layer of low-permeability fines separating two liquefiable sandy layers, showed evidence suggesting that material boiled from the lower sand to the upper sand in the absence of a drain through the fines. All of the experiments suggest that the presence of unblocked vertical drains prevent water film formation.