硫酸镁侵蚀环境下玄武岩纤维混凝土耐腐蚀及力学性能劣化研究

为了增强混凝土的抗侵蚀性能,对不同纤维掺量混凝土在硫酸镁侵蚀下的耐久性及力学性能进行了试验研究及分析。采用100mm×100mm×100mm的试块,纤维掺量分别为0%、0.05%、0.1%、0.2%、0.3%,浸泡于浓度为5.0%的硫酸镁溶液中,每30d观测表观裂缝、测试吸水率变化;每90d测定力学性能变化,并进行离子浓度测量。结果表明:玄武岩纤维对混凝土承载力及变形能力有一定的提高;玄武岩纤维混凝土与普通混凝土在硫酸镁溶液环境中相比,孔隙率增加速度较慢;但过量纤维反而对耐久性能产生不利影响;玄武岩掺量在0.1%左右时最为经济、合理。另外,针对玄武岩纤维离散困难的问题,提出了粉体颗粒玄武岩纤维离散法。本文研究可为玄武岩纤维混凝土的工程应用提供一定基础。

Study on corrosion resistance and mechanical property degradation of basalt fiber reinforced concrete under magnesium sulfate erosion environment

In order to enhance the corrosion resistance of concrete,the durability and mechanical properties of concrete with different fiber content under magnesium sulfate corrosion are studied and analyzed in this paper.The test block is 100mm×100mm×100mm,and the fiber contentsare 0%,0.05%,0.1%,0.2%,0.3%,and immersed in a magnesium sulfate solution with a concentration of 5.0%.The apparent crack is observed,and the water absorption rate change was tested both every 30d.And mechanical properties were measured every 90d and ion concentration measurements were taken.Through research,the main conclusions are as follows:basalt fiber can improve the bearing capacity and deformation capacity of concrete.Compared with the ordinary concrete,the porosity of basalt fiber concrete increases slowly in the environment of magnesium sulfate.However,excessive fiber has adverse effects on durability.When the basalt parameter is around 0.1%,it is most economical and reasonable.In addition,in order to solve the problem of difficult dispersion of basalt fiber,this paper puts forward the"dispersion method of basalt fiber with powder particles".This paper provides a certain research basis for the engineering application of basalt fiber concrete.