대상기초에서 지반반력계수 산정을 위한 재하길이비

Abstract

When estimating the coefficient of subgrade reaction at the strip foundation such as the buried box structure, the loading area of foundation is defined by the loading length of foundation (L). However, there are no clear design criteria for the loading length to be applied for a given width of foundation in practice. Accordingly, the purpose of this study is to suggest the most appropriate loading length ratio (L/B) of the foundation for the estimation of the coefficient of subgrade reaction, which can produce the most economical structure design in earthquake-resistant design. The main points of this study are as follows: (1) in the ordinary analysis without seismic force, the coefficient of subgrade reaction has little effects on the section forces (shear force and bending moment) of the structure. (2) In the earthquake-resistant design, if the loading length of foundation (L) is largely applied to a given foundation width (B), the value of coefficient of subgrade reaction is evaluated small, and eventually, a reduction ratio corresponding to the appearing section force. To estimate the optimum value of the coefficient of subgrade reaction for the most economical earthquake-resistant design, this study was to suggest setting the loading length of foundation (L) equal to the width of foundation (B); (that is, L/B=1).