Void ratio effect on dynamic shear modulus and shear wave velocity for soil stiffness in Banda Aceh and Aceh Besar

Aceh located in earthquake disaster-prone area because it is located between two tectonic plates and also surrounded by several active volcanos. When earthquakes shake, the building frequency (f) should not be equal to the natural soil frequency (f(n)) as it may cause the collapse of buildings. The purpose of this study is to determine dynamic seismic parameters value on the surface layers for forthcoming disaster mitigation. The object study for this research were Rahmatullah Lampuuk Mosque, Sultan Iskandar Muda Airport, Lambaro Bridge in Aceh Besar, TDMRC building, and Taman Sari. Soil samplings from the locations and data obtained from the BMKG such as earthquake center map, coordinates, magnitude, and earthquake depths were used in the study. The result of this research was Gmax value based on Richart method. Kramer method was also used for computing the f(n) parameters. Some static and dynamic calculation of design parameter result from Rahmatullah Lampuuk Mosque shows that with void ratio (e) = 0.92, the Gmax = 266 x 10(3) kg/ms(2), Vs = 10.096 m/s and f(n) = 2.524 Hz. The comparison of f(n) and f(structure) = 2.50 Hz which not equal to zero make the building were safe from collapse during previous earthquakes in Aceh.