Experimental Study on Liquefaction Characteristics of Coral Gravelly Soils with Different Particle Size Distributions.

Many laboratory studies have shown that particle size distribution (PSD) affects the liquefaction susceptibility of granular materials. However, few studies have focused on the impact of PSD on coral particles. In this study, two different soil families were prepared: one with three levels of mean particle size (D₅₀) with identical uniformity coefficient (C_u)and the other with four levels of C_u with the same D₅₀ for coral gravelly soils. In addition, a series of undrained cyclic triaxial tests were conducted on coral gravelly particles with two groups of PSDs at a relative density of 40% and an adequate confining pressure of 100 kPa. The test results indicated that D₅₀ with identical C_u can affect the undrained cyclic behavior of coral gravelly particles. In contrast, C_u with identical D₅₀ does not impact the undrained cyclic behavior of coral gravelly particles. The developing pore water pressure was uniform when the sample was subjected to the same cyclic loading. For samples with changing D₅₀ values of 2.35, 4.70, and 7.05 mm, increasing D₅₀ improved the cyclic liquefaction resistance. For samples with changing C_u, increasing C_u in the range of 1.06–5.00 first increased and then decreased the liquefaction resistance. [ABSTRACT FROM AUTHOR]