循环孔隙水作用下混凝土动态特性试验研究Symbol`@@

对0、10、50次孔隙水循环下不同应变速率（10－5、10－4、10－3、10－2／s）的混凝土和中低应变速率（10－4、10－3／s）下不同孔隙水循环次数（0、10、50、100、200次）的混凝土进行了常三轴压缩试验，试件尺寸为φ300 mm×600 mm。对循环孔隙水压作用后混凝土的峰值应力物理力学参数的变化规律进行了统计分析，并对混凝土在不同加载速率下的吸能变化规律进行了分析。结果表明：随着应变速率增大，混凝土的峰值应力呈增大趋势，随孔隙水压循环次数的增加，峰值应力大体呈现先增大后减小的阶段性变化；混凝土的吸能能力随加载速率的增加，表现出明显增大的趋势。混凝土的吸能能力随孔隙水压循环次数的增加表现出一定的离散性，但整体上呈先增大后减小的趋势；选用基于 Weibull 统计理论的混凝土材料分段式动态损伤本构模型对试验数据进行拟合，经验证，此模型与试验结果吻合较好。

Experimental analysis of dynamic properties of concrete under cyclic pore water effects

Triaxial compression tests for concrete of size Φ300 mm×600 mm was carried out under different strain rate (10 -5 ,10 -4 ,10 -3 ,10 -2/s)in 0,10,50 cycle of pore water and low strain rate (10 -4/s,10 -3/s)in different cycles pore water pressure (0,10,50,100,200 times).Comparatively analysis the changes law characteristics about of basic physical mechanics parameters,such as peak stress and absorption of concrete under different loading rate are analyzed.The results show that:concrete peak stress increases with strain rate and with the number of pore water pressure cycles,.the concrete peak stress increases at the first and then declines.with the number of pore water pressure cycles,shows the change of stages;Concrete absorption energy capability is loaded with the strain rate,and showed significant increasing trend.Energy absorption capacity of concrete pore water pressure increases with the number of cycles showed shows some discrete,but overall increase first and then decrease;Finally,choose sectional dynamic damage constitutive model of concrete material which is based on statistical theory Weibull is applied to of sectional dynamic damage constitutive model based on Weibull for analyse concrete material fitting oto fit with f experimental data,verified,and the results show that this model has good agreement with the test results.