Experimental study on damage law of fully graded concrete under tension compression cyclic load

Considering the reciprocating action of seismic load and the high compressive stress level of high arch dam, the damage law of fully graded concrete under tension compression cyclic load is studied. Based on 15MN large-scale dynamic material testing machine and specially designed linking device, the complete stress-strain curve of full graded concrete under cyclic load is obtained by means of high-precision axial extensometer and VIC-3D. The test data show that even at the medium and low pressure stress level, the full graded concrete will produce a certain amount of residual deformation, and has a good linear relationship with the pressure. Because the difference of ultimate strain between tension and compression of concrete is about 10 times, the compressive residual has great influence on the ultimate tensile strain. Ignoring the residual deformation under high pressure will overestimate the tensile strength of fully graded concrete, which is unsafe. Based on the stress-strain curve of tensile damage of fully graded concrete, it can be seen that the elastic modulus of fully graded concrete cannot be recovered immediately after tension compression conversion, but there is an obvious transition zone. The calculation results of the model ignoring the transition zone are unsafe.