承载混凝土酸雨侵蚀中性化试验研究

Investigation of Neutralization of Concrete under Loads by Accelerated Acid Rain Test

随着环境的恶化,酸雨侵蚀对工程结构的危害越来越大,酸雨侵蚀引起的混凝土耐久性问题已引起全世界的关注。由于实际工程中的混凝土结构绝大多数都是在承载状态下运行的,因此,本文通过承载混凝土的酸雨侵蚀试验,研究了工程中广泛应用的粉煤灰混凝土的酸雨侵蚀规律与中性化规律,重点分析了混凝土构件所承受的应力水平和粉煤灰掺量对混凝土中性化的影响。结果表明,弯曲拉应力对混凝土的酸雨腐蚀有加速作用,应力水平越高,加速作用越明显;弯曲压应力将减缓酸雨对混凝土的腐蚀;粉煤灰掺量越大,混凝土中性化深度越大,混凝土酸雨腐蚀越严重。

As the deterioration of environment, the effect of acid rain on concrete structures is even more serious. The durability problems caused by acid rain are increasingly concerned by the worldwide. As the majority of concrete structures were actually under loads, the neutralization of fly ash concrete under loads subjected to the simultaneous attack of acid rain was investigated by laboratory test in this paper. And the influence of stress level and fly ash replacement on neutralization of fly ash concrete was analyzed. It was found that, the bending tensile stress accelerated the acid rain attack. The higher the stress level, the more serious the concrete corrosion. In contrast, the bending compressive stress slowed down the acid rain attack. The results also showed that the neutralization depth of fly ash concrete was increasing and concrete corrosion attacked by acid rain was more serious as the fly ash replacement increased.