A Study of Undrained Behavior of Saturated Sand and The Concept of Steady State
No Thumbnail Available
Date
2005-01
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
It has been very common to see collapse of structures, slopes, and foundations due to flow of
foundation soils without observing any structural failure during earthquake. This can also
occur frequently and cause severe damages in this country following the occurrence of
earthquake, particularly in the Rift Valley region where there is a considerable deposit of
saturated sand and silty sand. This problem has been studied in various countries and
attributed to Liquefaction Phenomenon. The phenomenon occurs in saturated sand, which
either completely loses its strength and flow as a liquid (Flow Liquefaction, F.L) or shows a
progressive softening (Cyclic Mobility, C.M.) under cyclic loading. Since liquefaction of
sand is entirely related to its undrained behavior, the undrained behavior of saturated sand
under cyclic or equivalent monotonic loading has been studied in the laboratory by different
researchers, simulating field conditions properly for the better understanding of liquefaction
phenomenon. The undrained behavior of saturated sand is useful to predict the occurrence of
the probable type of liquefaction (C.M. or F.L) and to provide suitable solutions for
liquefaction problem.
The objective of this research is therefore to study the undrained behavior of saturated sand
in relation to liquefaction phenomenon based on intensive literature survey. This is best
explained by identifying factors affecting the behavior and studying their effects observing
the resulting stress-strain and p-q diagrams. The concept of Liquefaction and steady state
are then discussed based on the undrained behavior of sand. Finally, the application of Steady
State Line (SSL) on the assessment of liquefaction potential and in the identification of
partial liquefaction, limited liquefaction, and complete liquefaction is discussed.
Description
Keywords
Partial Liquefaction; Limited Liquefaction; and Complete Liquefaction