钢纤维混凝土冻融和碳化后力学性能试验研究

通过对混凝土试件进行室内快速冻融和碳化试验,测试并分析了混凝土试件在冻融循环和碳化作用后的基本力学指标,探讨了钢纤维体积率、混凝土强度等级、冻融循环次数及碳化龄期对混凝土基本力学性能的影响.试验结果表明:冻融循环损伤了混凝土的力学性能,强度较低混凝土力学性能的损伤较强度较高为严重;碳化对混凝土的密实性有加强作用,并会提高其相对抗压、劈拉强度.适量的钢纤维掺量和较小的水灰比改善了混凝土微观结构,抑制了混凝土的冻融速度,提高了混凝土的抗裂性能和抗碳化性能.

Tentative study on the mechanical property under the action of freeze-thaw and carbonation of steel fiber reinforced concrete

In the experiment,the compressive strength,splitting strength and rupture strength of steel fiber reinforced concrete after freeze-thaw were tested and analyzed through rapid freeze-thaw and carbonation experiment respectively in the lab.The influence of the volume fraction of steel fiber,the grade of concrete strength,the freeze-thaw circulation times and the carbonation time on the mechanical property was discussed.The results show that the mechanical properties of concrete are deteriorated by freeze-thaw cycles.The result of the lower strength of concrete will be more seriously deteriorated.Carbonation increases the density of concrete,the relative compressive strength and the relative rupture strength. The suitable volume fraction of the steel fiber and lower water cement ratio can improve the structure of concrete,restrain the speed of freeze-thaw and increase the resistance-crack performance as well as the durability of carbonation resistance.