腐蚀环境下混凝土火灾后的化学成分分析  

Corrosive environment analysis of chemical composition of the concrete after fire

作　　者：王剑[1] 高立堂[1] 范宏[1] 

机构地区：[1]青岛理工大学土木工程学院,山东青岛266033

出　　处：《混凝土》2015年第7期22-25,30,共5页Concrete

基　　金：国家自然科学基金项目(51178232)

摘　　要：腐蚀环境下的混凝土在遭受火灾时,烟气往往含有大量的强腐蚀性物质,并极易在混凝土表面结露形成强酸液,大量氯离子、硫酸根离子和硝酸根离子入侵而引起钢筋锈蚀,继而导致混凝土膨胀开裂对整个结构造成危害。针对这一问题,以受火灾影响后的海水脱硫吸收塔为背景,通过实际取样,并分层研磨,对其进行化学分析,研究各化学成分对混凝土结构的影响。结果表明:碳化对高温腐蚀环境下的混凝土影响较大,容易发生疏松或脱落情况,相对于硫酸根离子和硝酸根离子,氯离子的侵入量较大,采取相应的防腐处理措施,可以有效的减少火灾对腐蚀环境下混凝土的破坏。Concrete corrosive environment after suffering fire. The flue gas often contains a lot of strong corrosive substances and it is easy to form strong acid condensation on the surface of concrete,a large number of chloride ions,sulfate ions and nitrate ions cause the corrosion of steel,which in turn results in the expansion and crack of the concrete that makes harm to the entire structure. To solve this problem,through the power plant absorption tower affected by fire,take the actual sampling and layered grinding,chemical analysis, study on the influence of the chemical composition of concrete structure. The results show that effect of high temperature on carbonation of concrete is larger under corrosive environment,prone to loose or fall off the situation,with respect to the sulfate ion and nitrate ions, the intrusion of chlorine ions is larger. Use the appropriate corrosive preservative treatment,can effectively reduce the damage of con-crete after fire that in corrosion environment.

关 键 词：火灾 混凝土 碳化 氯离子 硫酸根离子 硝酸根离子 

分 类 号：TU528.01[建筑科学—建筑技术科学]