Research On Seismic Response Of Ground Fissure Site Under Earthquake And Its Ground-motion Parameters

In our country and even in the world, Xi'an is the region that ground fissure has most developed and the disaster is the most serious, meanwhile, urban construction have been seriously affected. In later years, with Xi'an ground fissure activity has been stabilized and the need of country development, new requirements on the use of ground fissure sites has been putted forward. Xi'an metro lines, which have been operated and are constructing, are all across ground fissure, and the use of ground on the ground fissure sites are also exploring. Although the study of ground fissure's distribution, characteristics, formation mechanism and prevention measures is fruitful, the seismic effect and the ground motion parameters of ground fissure sites, which are always lake of study and controversial. In addition, Xi'an locate in Fen-wei Basin which has strong tectonic movement, it has occurred earthquake many times in history and will occur in the future possibly. Therefore, it is particularly urgent to take research on ground fissure site's seismic effect in Xi'an city which ground fissure is distributed densely, and has important engineering significance.Firstly, the disadvantages of urban construction caused by ground fissures were analyzed through site investigation and satellite map.Secondly, the seismic response of a f4 ground fissure site and a common site with the same soil structure were analyzed by ABAQUS. According to the finite element results, the distribution and characteristics of positive and negative peak acceleration affected by different direction of peak acceleration, intensity and peak displacement of seismic wave were analyzed; the “amplification-effect” and “hanging wall and footwall effect” were analyzed through the case of acceleration mutation and the structural form of ground fissure site.Finally, the distribution and characteristics of predominant and mean period, which were selected at the surface of ground fissure site under earthquake, were analyzed; the difference of seismic-wave energy between ground-fissure site and normal site was compared, and the distribution and the characteristics of seismic wave energy were explored; A suggestion about evaluate of seismic-wave energy, which analyzed on ground-fissure site, was put forward.