CALCULATION OF EQUIVALENT STATIC LOADS AND ITS APPLICATION

摘要

All the forces in the real world act dynamically on structures. Since dynamic loads are extremely difficult to handle inanalysis and design, static loads are usually utilized with dynamic factors. Static loads are especially exploited well instructural optimization where many analyses are carried out. However, the dynamic factors are not determined logically.Therefore, structural engineers often come up with unreliable solutions. An analytical method based on modal analysis isproposed for the transformation of dynamic loads into equivalent static loads (ESLs). The ESLs are calculated to generate anidentical displacement field with that from dynamic loads at a certain time. The process is derived and evaluatedmathematically by using the modal analysis. Since the exact solution is extremely expensive, some approximation methodsare proposed. Error analyses have been conducted for the approximation methods. Standard examples for structural designare selected and solved by the proposed method. Applications of the method to structural optimization are discussed.