Column tests investigating the liquefaction of partially saturated loose non-plastic soils: Fid-Bau Portal

Column tests investigating the liquefaction of partially saturated loose non-plastic soils

Kwa, K.A. / Hu, Y. / Chen, J. / Chen, Z. / Airey, D.W.

Abstract This study reports data and findings from shake table tests performed on loosely compacted unsaturated well graded materials containing a wide range of particle sizes and significant fines contents of 18 to 28%. The results are useful for understanding the fundamental cyclic liquefaction behaviour of these unsaturated well graded materials when subjected to vertical cyclic loading conditions relevant to repetitive transport loading or during bulk cargo shipping transportation. Liquefaction was observed in all the shake table tests performed on the well-graded materials, which were prepared at relative densities of 50 to 60% and degrees of saturation ranging from 50 to 70%. Large settlements were also observed in the columns of the well-graded materials, which resulted in significant increases in the degree of saturation towards fully saturated states. Migration of fines throughout the well-graded materials was also observed, which also contributed to settlement and resulted in different local densities and fines contents throughout the column. The resulting build-up in pore pressures, settlements and accompanying increases in degree of saturation and movement of moisture throughout are presented and compared with shake table tests performed on columns of partially saturated clean sand for which liquefaction was not observed.

Highlights • This paper presents and discusses the experimental results obtained from shake table column tests performed on unsaturated well graded materials containing a wide range of particle sizes and a significant amount of fines. • These kinds of well graded materials have been less commonly tested than sands and silty sands even though these well graded materials are also susceptible to liquefaction and underlie much of the world's infrastructure and are widely used for land reclamation and subgrades for railway ballast and highway pavements. • Pore pressure, moisture content and settlement data are presented and analysed to describe the fundamental liquefaction behaviour observed during shaking of the unsaturated well graded materials.