黄铁矿岩石微生物风化作用的试验研究

岩石风化会造成岩体结构改变和物理力学性质恶化,造成工程失效和地质灾害。岩石风化尽管受到了岩土工程学家的关注,但对岩石生物-化学作用仍是需要关注的重要内容,特别是对富含硫化物的黑色岩石和煤系地层。以黄铁矿岩石为研究对象,通过微生物风化作用试验研究结果表明:微生物作用可使黄铁矿岩石的风化速率提高1个数量级,形成酸度更低,腐蚀性更强的水环境;在微生物作用下,黄铁矿硫化物等会加速风化,造成岩体结构破坏;黄铁矿风化形成的酸性水环境会腐蚀长石等岩石骨架矿物,恶化岩体完整性,降低岩体强度,从而导致很多工程事故和地质灾害

Analysis on Weathering of Rock under Microbial Condition and Its Destructive Action for Rock Mass

Rock weathering may cause it to be subject to structural change and deterioration of its physical and mechanical properties, resulting in invalid engineering and geological disaster. Although rock weathering has been concerned by geotechnical engineers, the biological-chemical action on rock are important, especially for the black rock and coal measure strata with rich sulfide content. Taking pyrite rock as the study object, the test for weathering by microorganism shows that, under the action of microorganism, not only the weathering rate of pyrite rock may enhance by 1 order of magnitude, forming a hydrographic environment with lower acidity and stronger corrosivity, but also pyrite-bearing sulfide may suffer accelerated weathering, leading to structural damage of rock mass ; the acid hydrographic environment from pyrite weathering may erode the mineral of rock framework, such as feldspar, which will deteriorate rock integrity and reduce rock strength, hence giving rise to engineering accidents and geological disasters. In prevention of rock weathering, it should pay attention to control moisture content and environmental microorganism, as well as reduce the reproduction speed of microorganism and redox potential.