Dynamic Properties of Soil in UAE from Field and Laboratory Tests

Abstract

Dynamic properties of soil are important for the design of structures under seismic loadings. The United Arab Emirates (UAE) is experiencing significant construction development; however, there is no systematic study to characterize the regional soils for dynamic properties. Therefore, designers have to rely on correlations of dynamic properties with other static parameters. These correlations are mostly developed for other regions which may not be suitable for the UAE. This research presents the findings of a laboratory testing program involving cyclic and static triaxial (CT) tests along with bender element (BE) testing on representative samples of regional soils. The bender element tests are used to evaluate the low strain shear wave velocity (Vs), whereas the cyclic triaxial (CT) test is used to evaluate the shear modulus (G) and the damping ratio (ξ) at different strain levels and confinement pressures. Correlations of Vs with Standard Penetration Tests N (SPT-N) values are developed. Two different sample sizes are used to evaluate the effect of sample size on dynamic properties. Static triaxial tests are also performed to develop correlations between Vs and friction angle (ɸ). The results of the experimental program indicate that the degradation of dynamic properties generally agrees with previous studies however the model parameters are different. The correlation of Vs with SPT-N values follows a power model whereas the correlation between Vs and friction angle presents as a linear model. A comparison of developed correlations with previous studies validates the importance of regional specific nature of soils as most of the models in literature neither agree with each other nor with the findings of this study.