Papers by Author: Ru Heng Wang

Abstract: Duncan-Chang model can reflect soil’s nonlinear behavior much better, its’ concept is clear and easy to understand. In this paper, through triaxial test, parameters of Duncan-Chang model were gained by analyzing characteristics of Silt’s stress-strain Cures. A key factor, effecting silt’s stability, is the moisture content; there is a optimum moisture content in silt, in this moisture content, silt’s parameters of Duncan-Chang model can reach to the optimal state.

Abstract: Concrete is a typical kind of rate sensitive material. In this paper, the concrete specimens were tested in the SHPB experiment system. Based on H-J-C constitutive model, the SHPB experiment was simulated by LS-DANY. The stress-strain curves which were gat from numerical simulation in the LS-DANY were compared with the stress-strain curves which were gat from SHPB. The results showed that the H-J-C constitutive could simulate the dynamic characteristics of concrete both under room temperature. The result also showed that the concrete was strain rate sensitive. Based on the numerical simulation, the stress wave in the SHPB system was studied. The research of the numerical simulation showed that the stress waves tended to become stable after several oscillations in the incident bar. At the same time, stress wave of elements in r=0 (The distance of elements to the axis was 0) were bigger than the stress wave of r=0.5R (The distance to the axis was 0.5R) and r=R (The distance to the axis was R).

Abstract: Using microwave heating method to establish a set of effective technology about uniaxial compression test of concrete, and obtain the experiment phenomenon of concrete when the temperature is 16 -650 . Experiment results indicate that when concrete is damaged by high temperature, the strength of concrete decreases, the peak strain increases, and the elastic modulus decreases. Based on test data, a unified equation was putted forward to describe the relation between concrete compressive strength, the peak strain, elastic modulus and temperature. While, obtain concrete temperature stress and strain curve, and analysis shows that it gradually becomes compressed with the increase of temperature, peak point falls and moves right obviously.