Investigation of the impact of excavation (reinforced) on the seismic behavior of adjacent steel structures under the influence of near-fault and far-fault earthquakes
Every year, as a result of earthquake, abundant losses may be created as result of roof motion and sliding and rupture. Under normal conditions, the ground and soils forming the ground tolerate and transfer the existing stresses and any kind of action like excavation and release of trench and applying dynamic load could distort the balance of stresses and endanger stability of roof. In this study, behavior of a steel building in adjacency of excavation is studied. The pit is stabled using hybrid system of pinching and anchoring and is studied before and after excavation under the effect of far and near-fault earthquakes with regard to soil-structure interaction. The results obtained from nonlinear dynamic analysis of time history of two said spectrums showed that the momentum of floor in the structure after excavation is increased compared to the time before excavation. The momentum of floor in the desired structure in near-fault earthquake has been increased compared to far-fault earthquake before excavation compared to the time after excavation. However, the overall drift of floors in the structure before excavation in near-fault earthquakes has been increased more than far-fault earthquakes.
Keywords: excavation, earthquake, far and near-fault zone, dynamic behavior, soil-structure interaction, steel structure