不同温度条件下水泥混凝土撞击后力学性能数值模拟研究

Numerical simulation study on mechanical properties of cement concrete after impact under different temperature conditions

对不同温度条件下的混凝土撞击后的力学性能模拟进行了研究,结果表明:对于单轴冲击压缩试验,冲击速度相同,如果混凝土材料的温度处于405℃以内的条件下,受到温度升高的影响抗压强度虽然会随之增大,但幅度较小;如果混凝土材料的温度已经高于405℃,在温度升高的影响下抗压强度则有较大幅度的改变,呈现出快速下降的趋势。当温度从25℃增加到805℃时,在冲击速度为7.5 m/s时,混凝土峰值应力降低65.56%;冲击速度为13.5 m/s时,混凝土峰值应力降低63.87%;冲击速度为17.5 m/s时,混凝土峰值应力降低44.25%。这说明随着温度损伤效应增强,材料强度增幅有所降低。不同温度的混凝土试件冲击速度变化规律表明,材料的峰值应力随冲击速度提高先增加后减小,最终趋于稳定。

It studies the numerical simulation of the mechanical properties of cement concrete after impact under different temperature conditions,and the results show that for uniaxial impact compression test,when the temperature is lower than 405 C at the same impact speed,the compressive strength of concrete material increases slightly with the increase of temperature,and when the temperature exceeds 405℃,thecompressivestrengthof concretedecreasessharply withtheincreaseof temperature.When thetemperatureincreasesfrom25℃to 805 C,the peak stress of concrete decreases by 65.56%when the impact velocity is 7.5 m/s.When the impact velocity is 13.5 m/s,the peak stress of concrete is reduced by 63.87%.When the impact velocity is 17.5 m/s,the peak stress of concrete decreases by 44.25%,which indicates that the increase in material strength decreases with the enhancement of temperature damage effect.The variation law of impact velocity of concrete specimens at different temperatures shows that the peak stress of the material first increases and then decreases with the increase of impact velocity,and finally tends to be stable.