不可移动石质文物岩石理化性质研究——以重庆市石佛寺遗址摩崖造像区为例

Physicochemical properties of immovable stone relics:a case study of Moya statue area of Shifosi Site in Chongqing

以重庆市石佛寺遗址摩崖造像区为工程背景,通过开展野外勘测及岩石试样的理化性质测试,提出一种针对不可移动石质文物的理化性质研究方法,即跨尺度分析方法。室内试验采用宏观试验及微观试验,宏观试验包括三轴试验和直剪试验,微观试验包括扫描电子显微镜(SEM)和X射线衍射(XRD)分析。采用宏观试验测得样品的基本力学参数;通过电镜分析可知,试样为标准的砂岩,孔隙率较大,表明其对水的敏感性较高,在长期干湿循环作用下,其强度会随着时间的推移而降低,即典型的水岩相互作用;XRD衍射试验表明,由于砂岩中黏土矿物含量较高,故其水理性质较差,抗风化能力较弱,这是导致其风化的主要原因。地质雷达勘测及辅助声波探测表明,在有效保护文物的前提下,可以采用该方法对文物进行宏观和微观的跨尺度科学分析。

Take Moya statue area of Shifosi cite in Chongqing as the engineering background,this paper proposes a research method for determination of the physicochemical properties of stone relics that cannot be moved through field survey as well as the application of cross-scale analysis method in immovable stone cultural relics.Laboratory tests were conducted by macro and micro tests,and the former include triaxial tests and direct shear tests,which were used to measure the basic mechanical parameters of samples.The micro tests include scanning electron microscopy(SEM)and X-ray diffraction(XRD)analysis.Through SEM,it can be seen that the sample is standard sandstone of large porosity,indicating that it is highly sensitive to water.In the long-term dry-wet cycle,its strength will decrease with time,namely,the typical water-rock interaction;XRD experiments show that the high content of clay minerals in sandstone leads to poor hydrologic properties and weak weathering resistance,which is also the main reason for weathering.Geological radar survey and auxiliary acoustic detection show that this method can be used to carry out macroscopic and microscopic cross-scale scientific analysis of cultural relics under the premise of effective protection of cultural relics.