OPTIMUM DESIGN OF SEMI-GRAVITY RETAINING WALL SUBJECTED TO STATIC AND SEISMIC LOADS

A 2D (Plain strain) wall?backfill?foundation interaction is modeled using finite element method by ANSYS to find the optimum design based on the principle of soil-structure interactions analyses. A semi-gravity retaining wall subjected to static and seismic loads has been considered in this research. Seismic records which are obtained from the records of Iraq for the period 1900-1988. The optimization process is simulated by ANSYS /APDL language programming depending on the available optimization commands. The objective function of optimization process OBJ is to minimize the cross-sectional area of the retaining wall. The results showed that the optimum design method via ANSYS is a successful strategy prompts to optimum values of cross?sectional area with both safety and stability factors as compared with other optimum design methods. Also, the results showed that the area of optimum section by ANSYS method is lesser than the section area of the GAs algorithm , PSO, and CSS methods by percentages are equal to 15.04%, 23.92%, and 25.33%; respectively, when   3.Additionally, from studying the effect of some parameters such as Compressive Strength of Concrete (? ) and Yielding Strength of Steel (   on cross-sectional area and reinforced area, is provided that the (´) and have small effect or do not effect on the value of crosssectional area () and this is due to the lack of weight ratio of steel reinforcement to concrete weight. Moreover, the yielding strength of steel has larger effect than compressive strength of concrete in the reinforcement area.