大足大佛湾石刻岩石微观与力学特性研究

为了给大佛湾石刻造像的病害治理提供依据,采用X射线衍射、光学显微镜、扫描电镜和岩石力学试验系统等对该区域内岩样的矿物成分、微观结构和力学特性进行分析。结果表明,石刻区域内岩石的矿物成分以石英、钠长石、方解石、黏土矿物为主,且由于黏土矿物和方解石的含量与分布不同,造成了砂岩外观颜色的差异;区域内岩层没有变形改造,砂岩内部存在较多微孔隙而泥质砂岩、泥岩的结构较为致密,且水对岩石的结构有溶蚀、淋滤等破坏;区域内岩石的力学性质受黏土矿物的影响较大,通过力学试验得出的基本力学参数显示,与天然状态相比,岩样在饱水状态下的强度明显降低。

Microscopic and mechanical characteristics of rocks near Big Buddha Bay Rock Carvings in Dazu

In order to provide reference for disease management of the stone statues in Big Buddha Bay, mineral composition, microstructure and mechanical properties of the rock samples were analyzed by X-ray diffraction, optical microscopy, scanning electron microscopy and rock mechanics test system. The results show that mineral composition of the rocks in the stone carving area mainly includes quartz, albite, calcite and clay minerals, and different contents and distribution of the clay minerals and calcite result in different appearances and colors of the sandstone samples. There is no deformation in the rook strata in this area. Many micro-pores exist in sandstone and the structures of argillaceous sandstone and mudstone are denser. Corrosion and leaching by water damage the structure of the rocks. Clay minerals have a great influence on the mechanical properties of the rocks in this region. Basic mechanical parameters obtained by mechanical tests indicate that strength of water-saturated rock samples is significantly lower than that of rock samples in the natural state.