抄録
It is well known that the failure of mortar or concrete is the statistical phenomina since "weak points" are distributed at random in a specimen, and that, therfore, there is a need of introduction of the statistical methods for the analysis of the failure. The objects of this papers are to propose a statistical model to analyze mortar or concrete strength from the standpoint of a statistical aspect. In this papers, we have introduced an idea of transition rate λ_i(t) which a specimen in a state at time t changes to the next one so that we might discuss the failure problems in term of stochastic theory. The characteristic distribution of the failure time under sustained load and periodic load, and the size effect, the dispersion and the effect of loading rate in the static strength have been analyzed, based on this statistical model. The results were that this statistical model is possible to represent the experimental facts in the creep life, the fatigue life and the static strength of mortar or concrete.
