Effects of loess content on dynamic shear modulus and damping ratio of Taiyuan sand

The mixtures of loess and Taiyuan sand are distributed widely along the No. 2 metro line of Taiyuan, which leads to an urgent need for the dynamic shear modulus G and damping ratio λ to analyze the seismic response. The resonant column tests on remodeling silty sand with various loess contents (LC) are conducted by the GDS-RCA apparatus made by GDS Instruments Ltd. from the UK. The results show that the load bearing frame of the mixtures is changed from sand to soil particle with the increase of LC, which leads to the property difference of the mixtures with various LCs. The G of the mixtures decreases firstly and then increases with the increase of LC. However, the change of λ is opposite. The threshold loess content LC_th exists obviously. The LC_th of the saturated and dried samples is different. The size relationship between the G and λ of mixtures and Taiyuan sand is dependent on the LC in the dried state. As for the loess plasticity, the G of the mixtures is smaller than that of Taiyuan sand, and the λ of the mixtures is larger than that of Taiyuan sand in the saturated state.