冻融循环对混凝土静动力特性的影响

发布时间：2018-06-07 09:27

本文选题：混凝土 + 冻融循环　；参考：《解放军理工大学学报(自然科学版)》2017年01期

【摘要】：为了解冻融循环对混凝土材料静、动态力学性能的影响规律,在清水和盐水中采用"快冻法"对C60混凝土进行了不同冻融次数后的单轴静压试验和霍布金森压杆冲击试验,分析了混凝土强度变化的原因。试验表明,清水和盐水条件下,混凝土试件的质量损失和相对动弹性模量的损失率随冻融次数的增加而增大,盐水环境中更明显。清水环境下的冻融循环对混凝土的静态抗压强度具有显著影响,但对其动态抗压强度影响不明显;盐水环境下,当冻融次数较少时,混凝土的动态强度表现显著的应变率效应且不受冻融循环次数的影响,但在冻融循环次数达到240次时,混凝土的动态强度显著下降且对冲击速度不再敏感。不同冻融环境对混凝土静、动态强度影响的差异显著。
[Abstract]:In order to understand the influence of freeze-thaw cycle on the static and dynamic mechanical properties of concrete, the uniaxial static pressure test and Hopkinson compression bar impact test of C60 concrete with different freeze-thaw times were carried out in clear water and brine water by "quick freezing method". The reason of the change of concrete strength is analyzed. The test results show that the mass loss and the relative dynamic elastic modulus loss rate of concrete specimens increase with the increase of freeze-thaw times under the condition of clear water and brine, especially in brine environment. The freeze-thaw cycle under clear water has a significant effect on the static compressive strength of concrete, but has no obvious effect on the dynamic compressive strength of concrete, while in brine environment, when the freeze-thaw times are less, The dynamic strength of concrete shows significant strain rate effect and is not affected by the number of freeze-thaw cycles, but when the number of freeze-thaw cycles reaches 240 times, the dynamic strength of concrete decreases significantly and is no longer sensitive to impact velocity. The influence of freeze-thaw environment on the static and dynamic strength of concrete is significant.
【作者单位】：解放军理工大学爆炸冲击防灾减灾国家重点实验室;南部战区陆军昆明工程科研设计所;
【基金】：国家重大科学仪器设备开发专项资助项目(2014YQ240445) 国家自然科学基金资助项目(51321064)
【分类号】：TU528

【参考文献】