|Budget Amount *help
¥2,100,000 (Direct Cost : ¥2,100,000)
Fiscal Year 1993 : ¥1,300,000 (Direct Cost : ¥1,300,000)
Fiscal Year 1992 : ¥800,000 (Direct Cost : ¥800,000)
Despite the fact that concrete is a composite material of mortar and aggregate, the analitical treatment in which it was modeled as averaged and uniform continuum has long been performed. However, recent progress of analisys, test and mesurement make it possible to attempt to investigate the mechanical characteristics of concrete taking acount of its components'proper characteristics, various phenomena on their boundary and time-dependent change due to hydration, development of micro-crack, creep. This approach of concrete study is particularly indispensable both in experiment and in analisys for high strengh concrete which is notably interested in recent years to examine its reliability.
In this study, first, the pre-processor is developed in which mortar part and aggregate part are separeted and shape, size and location of aggregates are randomly generated. Second, the BEM program is given in which aggregates are modeled as boundary elements. The effect of bond crack in mortar boundary is incorporated in this model and the crack generation level and its consequence in the decrease of concrete stiffness are evaluated. According as the change of aggregate parameters, analisys simulation for randomness of aggregate location lead load-deformation relation which suggests the influence of aggregate content.
Transfer of the analisys tool into higher performance media in order to handle larger scale problems, and Incorporation of nonlinearity of mortar are quoted as further subjects to solve.