某高速公路路基红色泥岩微观结构试验研究

Experimental Study on Microstructure of Red Mudstone in Highway Subgrade

对某高速公路路基红色泥岩细观结构进行了试验研究。首先,利用X射线衍射对不同风化程度的红色泥岩、泥岩残积土进行图谱分析,得到泥质粉砂岩、紫红色泥岩和红色粉砂质泥岩中黏土矿物含量分别为45%,64%和50%,不同类型泥岩的黏土矿物在种类和数量上差别很大,由此引起工程性质差异明显。然后,利用电子显微镜扫描仪对紫红色泥岩、泥质粉砂岩及泥岩残积土进行微观结构测试,结果表明:红色泥岩的风化程度与矿物成分、微观结构密切相关,岩石风化改变了微观结构,进而影响岩石的宏观物理力学性质。

A study on mesostructure of red mudstone in a highway subgrade was made. Firstly, X-ray was used to analyze the spectrum of red mudstone and mudstone residual soil with different weathering degree. The results show that the clay mineral content in the muddy siltstone, magenta mudstone and red silty mudstone is 45 % , 64 % and 50 % respectively. The clay minerals of different types of mudstone are different in species and quantity, leading to obvious difference of engineering properties. Then, electron microscopy scanner was used to observe the microstructure of muddy sihstone, magenta mudstone and mudstone residual soil. The results show that the degree of weathering of red mudstone is closely related to mineral composition and microstructure. Rock weathering changes its microstructure, thereby affects the macroscopic physical and mechanical properties of rock.