Abstract:
By using a large static and dynamic electro hydraulic servo controlled testing system, the dynamic compressive tests of three graded large aggregate concrete with three kinds of water content (i.e. dry, natural and fully saturated) are carried out under different stress ratios (1:0, 1:0.25, 1:0.50, 1:0.75, 1:1.00) and strain rates (10-5/s, 10-4/s, 10-3/s, 10-2/s). In the test analyses, the effects of water content on the biaxial dynamic compressive strength of the three-graded large aggregate concrete are studied. A dynamic compression failure criterion of the large aggregate concrete is proposed. The experimental analysis results show that the compressive strength of the saturated concrete increases at the high strain rate, and decreases at the low strain rate. Comparing with the uniaxial compression, the compressive strength reaches the maximum value at the stress ratio of 1:0.5. It is found from experimental studies that the major factor influencing the failure pattern of the three-graded large aggregate concrete is the stress ratio. The dynamic ultimate compressive strength increases with an increase in water content, while the static ultimate compressive strength decreases with an increase in water content. The specimen under the uniaxial compression has less deformation than that under the biaxial compression, and the peak strain of the specimen is found to increase with the decrease of the strain rate.