Study On The Influence Of The City Load On The Ground Fissures Movement

Ground fissure is the main geological disaster in Xi'an city construction. Influence factors of Xi'an ground fissures movement are very complicated. Now, many researchers believe that the movement mode and intensity of the ground fissures are mainly controlled by the Lintong—Chang'an fault and the non-uniformity subsidence caused by excessively pumping ground water, especially the differential subsidence on both sides of the ground fissure is the major reason of intense movement of ground fissures at present. But there is few research on the relationship between the city load and the ground fissures.This paper through the comparison, analyzes the Xi'an ground fissures material, thought the Xi'an control pumping pressure groundwater, the pressure water level begin to rise, in this situation, the land subsidence mainly initiates by the land load. The performance is, the neighboring building monomer ground distorts mutually affects, mutually superimposes, forms the big area, the regional land subsidence. Therefore, Xi'an ground fissures' superior activity nearly ten years, is mainly because of the superimposition between non-uniformity subsidence that is caused by the city attachment load on both sides of the fissures and activity process of the fissures.This paper according to the actual material, research the distortion activity of land fissure by the analysis model. From finite element analysis(FEA) result that, as a result of load influence, on the one hand, in the surface following certain depth, nearby fissure the soil body receives the shear destruction, appears in the soil body interior hides the fissure. On the other hand, in the place crack two sides certain widths, forms the strain collection middle place, this kind of strain collection middle place can directly cause to the stronger additional stress in this scope. As a result of additional stress, the fissure of continual be able to appear the obvious attachment distortion, and the hides fissure will link up directly, thus the ground fissure destructiveness will be enlarged.At last, disaster protection measures for Xi'an ground fissures are simply discussed in this paper.