以云南地区在建大瑞铁路为依托，利用工程建设沿线———腾冲区域内丰富的天然火山灰资源，探讨了火山灰作为混凝土矿物掺合料应用于铁路路基加固与防护工程结构物中的可行性。通过基本力学性能试验、电通量试验以及为期两年的硫酸盐全浸泡试验，研究了火山灰混凝土的抗压强度、电通量以及抗化学侵蚀性能与火山灰掺量、养护龄期等的相关规律。研究表明，火山灰混凝土具有良好的力学性能和抗化学侵蚀能力，其抗化学侵蚀性能随其水胶比的降低而提高；单掺天然火山灰混凝土的电通量较基准混凝土有所降低，但无法满足铁路工程中的化学侵蚀环境要求。建议复掺硅灰来提高混凝土的抗环境侵蚀能力，满足铁路混凝土工程建设的要求。%The research relied on the a buliding Dali-Ruili railway in Yunnan province. The abundant natural vol-canic ash resource along the railway line was been utilized as mineral admixture into concrete binder, and its application practicability for the subgrade consolidation and protective engineering was discussed. Adopting the basic mechanics prop-erty test and dielectric flux test and the sulphate immersion test, correlative discipline between the compressive strength, the resistance to chemical attacking of the volcanic ash concrete and the mixing ratio, age of the volcanic ash concrete were expounded. The research show that the mechanical property and resistance to chemical attack of natural volcanic ash concrete are well, and they grow up with the decreasing level of water binder ratio. Passed electric charge of concrete with only natural volcanic ash reduces to lower than the reference concrete, but it isn’t up to the standard of the railway con-crete durability requirement for resistance to chemical attacking. Therefore, double mixing with silica fume is proposed to improve the resistance capability to chemical attack of concrete, which could satisfy the requirement of the railway con-crete engineering construction.
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