Computation of Dynamic Passive Earth Pressure Using LISP

Abstract

Few solution techniques exist for the determination of dynamic passive earth pressures for cohesionless soils. The pseudostatic dynamic Mononobe-Okabe equation is widely used to design structures that must resist earthquake loads. Researchers have noted that the Mononobe-Okabe equation assumes a planar failure surface, which is not the most critical mode of failure for determining the passive failure load. The goal of this research was to develop a more accurate method for computing pseudostatic dynamic passive earth pressures. This paper outlines the development of a computer-program-based solution assuming a log-spiral failure surface to compute pseudostatic dynamic passive earth pressure coefficients. The programming language COMMON LISP was used to develop the code. The features and capabilities of this programming language are not widely known outside the field of computer science. This paper illustrates the use of COMMON LISP in the formulation and solution of computationally intensive algorithms.