The use of unreinforced concrete members in foundation for construction projects is limited and needs further investigations. In this study, a nonlinear three-dimensional finite-element technique is used to analyse the load deflection of an unreinforced concrete beam resting on strip footings using the computer program ANSYS 5.4. The nonlinear equation was solved by the incremental and iterative running load procedure. A case study showed an excellent agreement between the theories of finite elements and practical case. We explored a new direction of using the computer program to evaluate the effects of the width, depth, and length of the foundations. In the analysis of the effect of the depth, six values of depth were used while the length and width were constant. With the increase in the depth, the deflection decreased. The effect of the width of the foundation was also investigated. With the increase in the width of the foundation, the deflection increased due to the increase in the concrete mass. With the increase in the length of the foundation, the deflection increased due to the decrease in the stiffness of the foundation. The present finite-element and available experiential results are in a good agreement. The differences do not exceed 6% in the ultimate load prediction and 15.6% in the deflection in case of using the interface element and critical state model. With the use of the developed computer program in this study, a distinctive agreement was obtained between the experimental and theoretical load-deflection curves and those obtained by four applications using the finite-element technique.