Minimum‐Weight Design of Machine Foundation under Vertical Load

Abstract

In this paper a numerical model for the minimum‐weight design of a rectangular machine foundation under a harmonic vertical load is presented. The analysis of the dynamics of foundation‐soil interaction is based on frequency‐dependent dynamic properties of a semi‐infinite supporting medium and includes the shape of the foundation plan, the embedment of the foundation into the soil, and hysteretic material damping of the soil. Dimensions of the concrete block are assumed as design variables. Constraints are placed on resonant frequency, vertical displacement amplitude, stresses in the soil and dimensions of the foundation concrete block. A sequential programming method with variable move limits is used to obtain the optimal solution, which is affected by inertia properties of the machine‐foundation‐soil system, damping from dynamic soil‐foundation interaction and local soil conditions. Numerical examples are given to demonstrate the applications of the proposed approach.