复合盐溶液浸泡下玄武岩纤维混凝土耐腐蚀性能的试验研究

Experimental Study on Corrosion Resistance of Basalt Fiber Concrete Soaked in Compound Salt Solutions

为探究南疆地区不同掺量玄武岩纤维混凝土的耐腐蚀性能,结合该地区的盐渍土壤环境,采用该地区既有结构所常用的强度等级C35混凝土,在混凝土中分别掺入体积掺量为0%、0.1%、0.2%、0.3%的玄武岩纤维,开展MgSO_(4)+Na_(2)SO_(4)+NaCl复合盐溶液浸泡下玄武岩纤维混凝土的耐腐蚀性能试验研究,选取试件的相对质量和相对弹性模量为主要指标进行分析评价。研究结果表明:当玄武岩纤维掺量为0.3%时,试件的相对质量、相对弹性模量的波动幅度较其他掺量试件的波动幅度小,说明此时混凝土抗复合盐溶液侵蚀的性能得到增强;由试件的微观结构分析可知,混凝土在MgSO_(4)+Na_(2)SO_(4)+NaCl复合盐溶液侵蚀下,其主要生成的产物为钙矾石和石膏,玄武岩纤维的掺入减少了腐蚀产物的生成,与其宏观指标变化具有一致性。

The corrosion resistance experiments of concrete with basalt fiber proportion of 0%,0.1%,0.2%and 0.3%were conducted,in which the conorete specimens were soaked in compound salt solutions of MgSO_(4) mixed with Na_(2)SO_(4) and NaCl,to explore the corrosion resistance of concrete specimens with different basalt fiber proportion.Based on the saline soil environment of the Southern Xinjiang area,the concrete of strength grade C35 commonly used in the existing structures in the area was adopted.The relative masses and relative of elastic moduli of specimens were selected as the main indexes for analysis and evaluation.The results showed that the fluctuation range of the relative masses and the relative elastic moduli of concrete specimens with the basalt fiber of 0.3%were lower than those of other specimens,which indicated that the resistance of concrete to erosion of compound salt solutions was improved.The analysis for microstructure of specimens showed that the main production composition in concrete immersed in compound salt solutions of MgSO_(4) mixed with Na_(2)SO_(4) and NaCl were ettringite and gypsum.The adding of basalt fibers reduced the generation of corrosion products,which was consistent with the change of its macroscopic indicators.