重庆大足卧佛造像砂岩表层风化现场试验测试  

In-Situ Study on Surface Sandstone Weathering Mechanism of of the Niche“Sakyamuni Entering Nirvana”at Dazu Rock Carvings in Chongqing

作　　者：马雨君 黄蕾 张景科[1] 铁铮 刘建辉 蒋思维 Ma Yujun;Huang Lei;Zhang Jingke;Tie Zheng;Liu Jianhui;Jiang Siwei

机构地区：[1]兰州大学土木工程与力学学院西部灾害与环境力学教育部重点实验室,兰州730000 [2]故宫博物院,北京100009 [3]中国文化遗产研究院,北京100029 [4]大足石刻研究院,大足402360

出　　处：《中国国家博物馆馆刊》2021年第12期126-137,共12页Journal of National Museum of China

基　　金：大足石刻宝顶山卧佛项目;小佛湾石刻造像保护修缮工程项目;甘肃省科技重大专项计划项目(项目编号:182D2FA001)资助

摘　　要：重庆市大足区宝顶山现存有大量珍贵石质文物,卧佛摩崖造像作为其中代表之一,其表面劣化一直是其价值保存的重大威胁。石像表面众多劣化病害中,粉化剥落所占面积最多、分布最广,对此前人所做调查研究工作涉及有室内模拟劣化试验、表面风化现状勘察等;研究选取了现场主要4处试验区域进行采样测试,并对造像试验区同类型的未风化砂岩岩芯样本做半定量矿物成分分析。结果表明:各风化面硬度值随高程的降低呈递减趋势,与岩石矿物成分分析测试结果中方解石含量变化相一致。样品电镜照片以及现场显微照片中,较大骨架颗粒间缺少联结,表面微裂隙发育明显。结合现场调查及以往研究资料,造像表面岩石风化程度不仅受地下水毛细上升作用的影响,同时受造像自身结构缺陷如软弱夹层、层理面以及层面等的影响。此研究成果将丰富石质文物自然风化机理的认识。The deterioration of surface is a major threat to the preservation of the famous niche“Sakyamuni entering nirvana”at the Dazu Rock Carvings in Chongqing.Among the numerous deterioration diseases on the surface of stone statues,powdering and spalling account for the largest area and are most widely distributed.Previous investigations and researches include indoor simulation degradation test and surface weathering status survey,etc.In this study,four main test areas were selected for sampling test,and semi-quantitative mineral composition analysis was conducted for the same type of fresh sandstone core samples in the imaging test area.The results show that the hardness value of each weathering surface decreases with the decrease of elevation,which is consistent with the change of calcite content in rock mineral composition analysis.In the SEM results and field micrographs of the samples,no connection is found between larger skeleton particles,and the surface microcracks are obviously developed.Combined with field investigation and previous research data,it can be inferred that the weathering degree of rock on the image surface is not only affected by capillary rise of groundwater,but also by its own structural defects such as weak interlayer,bedding plane or layer.This study will enrich the understanding of the natural weathering mechanism of stone heritages.

关 键 词：大足石刻 砂岩风化 风化机理 现场试验 

分 类 号：K879.3[历史地理—考古学及博物馆学]