Retaining Wall Design Optimization with MS Excel Solver

Using reinforced concrete retaining wall as an example, the purpose of this paper is to demonstrate that one does not have to be an optimization expert to take advantage of the power built into modern tools such as the Microsoft Excel. Worksheets designed for usual analysis and design computations can be turned into formal design optimization tools by simply choosing cells corresponding to design variables, objective function and suitable constraint functions. This way an optimum design can be obtained in a systematic manner without having to resort to manual trial and error process. The paper presents the worksheets for design of cantilever retaining walls and shows several optimum design examples. To further demonstrate the usefulness of these worksheets a sensitivity analysis is carried out that shows the effect on optimum cost of various parameters such as wall height, surcharge pressure, allowable soil pressure, and internal soil friction angle.