コンクリートのレオロジーに関する研究 : Maxwell, Burgers modelを用いた実験と解析

抄録

On account of the concrete is an inelastic material, it is well known that the compressive strength and the strain of concrete vary by the loading speed. And even though the small stress is acted to concrete, it take with the continous flow deformation. Althoug the concrete is regarded as a hook body in the first approximate, the mechanism of viscous flow is assumed as a Maxwell liquid or Burgers body in case of we consider a rheological behavior of it. We carried into execution the experimetal study on the effect which the loading speed have influence upon the strength and the strain of the hardening concrete. From the experimental results we calculated the coefficient of viscosity η_M of concrete appling the Maxwell model. According to our analytical results, the values of η_M vary by the loading speed (10^1, 10^0, 10^<-1> kg/cm^2sec), and it was found out in order 10^<12>, 10^<13>, 10^<14> poise. And also from the creep strain of concrete observed in about three or ten years author analyzed the coefficeint of viscosity useing the Burgers model. According to the calculating results η was obtained as following. η_M=10^<19>〜10^<20>, η_K=10^<17>〜10^<19> poise. By the aboving fact we deduced that the component of viscosity η of concrete consiste of the many grade. Arelaxation time τ_M and retardation time τ_K leaded from these η is τ_M=10^1〜10^9 sec, τ_K=10^7〜10^8 sec. Therefore we think that the rheological behavior of concrete must be considered by the conception of distribution function of relaxation time or retardation time.