Effect of Soil Friction on the Optimum Design of Cantilever Retaining Walls

In this study the Artificial Intelligent Method (AIM) was used to find safety factors against sliding, overturning and bearing capacity of cantilever type retaining wall. The method was also used to determine the optimum dimensions of retaining wall and consequently minimum retaining wall volume. Three parameters were investigated in this study: friction of the soil beneath and behind the retaining wall ( ), retaining wall height (H) and surcharge load (Q). approximately, zero constrains violation and constant volume of retaining wall were achieved through three iterations of solution. This results gave a reliability for using this method for optimum design of cantilever type retaining wall. The results demonstrated that, the significant increasing in sliding and bearing capacity factors of safety started at ( ), while the safety factor against overturning decreased with increasing soil friction up to ( ) and then increased. On the other hand, there is no change in base width of retaining wall when ( ) excessed ( ), and the optimum volume of retaining wall decreased significantly at this value of friction angle. Finally, the research concluded the possibility of using the results obtained from this study as a design charts to obtain the various retaining wall elements and different safety factors within the limits of studied parameters i.e, soil friction, height of retaining wall and surcharge load.