Explosion phenomenon has been most attractive subject for researchers during different era, from innovation of gunpowder to these days. The biggest of these researchers has been done during WW2. At last years, many terrorist attacks have been done by using explosion materials and bombs. Explosion is a chemical reaction; it finishes in some mill-second. During reaction a huge amount of energy release in the atmosphere and cause a pressure wave by high speed. Wave attacks building, impacts and forces them. In general, RC buildings have better reaction to explosion wave, because of their high mass. In this study, main goal is to observe the RC building under explosion load and finding ways to reduce or prevent damages. To model the RC building the ABAQUS Finite Element software has been used. For modeling it has been tried to make the model very close to the reality and to cover the proper details. The results show that distance has significant effect on reducing the explosion wave pressure and consequently on applied explosion loading.

Shear walls are one of the most lateral- forces resistant systems which have been nicknamed "shear walls" due to their high shear force absorption. Bending deformation of these structures is noticeable which results in great tensions at the foot of the wall. These walls are divided into two groups of reinforced concrete and steel walls and their behavior are different from each other. Reinforced concrete shear walls have high out- of- plane stiffness which prevents them from buckling but steel shear walls have low out- of- plane stiffness and their behavior is affected by diagonal traction fields which results in shear capacity reduction. In order to prevent these walls from buckling, steel plates are connected to concrete panels by means of shear studs. Coupling of steel shear walls changes their behavior and steel plates reach their ultimate capacity. Therefore, in this study, nonlinear static behavior and seismic parameters of composite shear walls system have been investigated. At the beginning of the research, a sample of the laboratory model has been verified to ensure the modeling of the composite shear wall in the nonlinear behavior range. In the next study, a double-skinned steel frame system and five-story compound shear walls were designed in a panel based on a reasonable behavior coefficient. In ABAQUS software, non-linear static modeling and analysis was performed and seismic parameters This system has been calculated for its behavior coefficient and shape. The results of the seismic parameters derived from this model are in good agreement with previous studies.

According to researches and experiments conducted by researchers, it is accepted that shear walls have significant structural parameters such as lateral stiffness, shear capacity and energy absorption. These walls are known for their shear force due to the shear force absorption, while flexural deformations occur, and stresses from the bending anchor at their feet are remarkable. Now, if we connect two adjacent and separate shear walls together with very difficult towed beams, the strength and behavioral properties of these walls will change greatly. So, to clarify this, at the beginning of the present study, the relationships between the elastic analysis of the system are reviewed in a continuous method. In the next study, a 10-story coupled shear wall system is compared with the results of ABAQUS software based on the continuous method of elastic analysis. According to studies, the lateral displacement in the system of the coupled shear walls is increased and the lateral stiffness decreases. Also, the bending anchor in the shear walls is sharply reduced relative to the uncoupled shear walls, but the shear force does not change in each of the walls, but very large shear force are formed in the coupled beams, which are Axial force is transmitted to the walls. In general, the presence of coupled beams in the system of uncoupled shear walls significantly reduces the stress at the foot of the walls and makes the lateral deformations in the walls to be flexed to the shear.