Saturation effects on calcareous desert sands: Ismael, N F; Al-Khalidi, O; Mollah, M A Trans Res RecN1089, 1986, P39–48

Abstract

Saturation of the surface desert sands in Kuwait has caused some problems of settlement and local slope failures. The surface soils, consisting of calcareous windblown fine sand or silty sand, are sensitive to saturation. Laboratory and field testing programs were conducted to examine the effect of saturation on the shear strength parameters, settlement under load, and the ultimate bearing capacity. Laboratory testing consisted of basic properties, direct shear tests, and consolidation tests on undisturbed samples under unsoaked and soaked conditions. The samples were trimmed from block samples taken from five sites where slight interparticle cementations exist. Field tests included standard penetration, static and dynamic cone penetration tests, and plate load tests. All field tests were performed at one site on samples under unsoaked and soaked conditions. The laboraory test results indicate a reduction of the shear strength parameters due to saturation and increased compressibility or settlement under load. The field tests indicate a loss of 25 percent in both the ultimate bearing capacity and the allowable soil pressure for a given settlement criterion at the site most sensitive to saturation along a 35-km (22-mi) corridor. An average ratio of 4 was calculated between the cone penetration of the surface sands.