摘要
重庆大足宝顶山大佛湾石刻存在严重的毛细水害及毛细水带来的盐害、生物等衍生病害,对该世界文化遗产的保护带来了长期负面作用。在对大佛湾进行现场调查的基础上,将造像摩崖砂岩划分为3套地层:卧佛上层砂岩、卧佛砂岩及卧佛下层砂岩。采用薄片鉴定、X射线衍射、化学成分测试、扫描电镜、压汞试验、卡斯特瓶法等方法,分析了宝顶山砂岩的自身特性以及温湿度对毛细不水的影响。研究结果表明:相对于卧佛上下层砂岩,卧佛本体砂岩的成熟度最低,孔隙率与孔隙的分布范围均最大,为毛细水的迁移提供了相对好的条件;卧佛本体砂岩毛细吸水能力及上升高度均为最好。同时,毛细水的上升与环境温湿度、空气流通性密切相关;在大足石刻的致密砂岩中,大量的贯通性微小孔隙在毛细水迁移中并不能发挥作用,卧佛本体砂岩有效孔隙直径应该在1133.0 nm以上,极端情况下可能达到760.2 nm。研究结果为准确认识大足石刻毛细水形成与演化提供了可靠的数据,解释了大足石刻冬季盐害的形成机理,对大足石刻毛细水治理提供了理论依据。
The Dafo Bay stone carvings in Baoding Mountain,Dazu District,Chongqing City,are suffering from serious capillary water damage,salt damage,biological and other derivative diseases caused by capillary water,which have brought a long-term negative effect on the protection of the world cultural heritage.Based on the field investigation of the Dafo Bay,the strata of the statuary cliff are divided into three sets:the upper sandstone of the reclining Buddha,the sandstone of the reclining Buddha and the lower sandstone of the reclining Buddha.Through a series of tests and experimental studies,the characteristics of sandstone in the Baoding Mountain area and the influence of temperature and humidity on capillary water are analyzed.The testing items include thin section identification,X-ray diffraction,chemical composition test,scanning electron microscopy,mercury injection test,Karsten tube penetration test,etc.The research results indicated that:compared with the upper and lower layers of the reclining Buddha sandstone,the Reclining Buddha body sandstone has the lowest maturity and the largest porosity and pore distribution range,which provides relatively good conditions for the migration of capillary water.The capillary water absorbability and capillary water elevation of the reclining Buddha body sandstone are the best,and the rise of capillary wateris closely related to the ambient temperature,relative humidity,and air circulation.In the tight sandstone of the Dazu Stone Carvings,a large number of interconnected micropores cannot play a role in the migration of capillary water.The effective pore diameter for capillary water migration in the reclining Buddha sandstone should be above 1133.0 nm,and may reach 760.2 nm in extreme cases.The research results provide reliable data for an accurate understanding of the formation and evolution of capillary water in Dazu Stone Carvings,explain the formation mechanism of salt damage in Dazu Stone Carvings in winter,and provide a theoretical basis for managing capillary water in Dazu Stone Carvings.
作者
宋佳航
严绍军
项伟
刘建辉
赵岗
蒋思维
Song Jiahang;Yan Shaojun;Xiang Wei;Liu Jianhui;Zhao Gang;Jiang Siwei(School of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;Shaanxi Institute for the Preservation of Cultural Heritage,Xi′an 710075,China;Chinese Academy of Cultural Heritage,Beijing 100029,China;Dazu Academy of Carved Stone,Chongqing 402360,China)
出处
《地质科技通报》
CAS
CSCD
北大核心
2022年第4期282-291,300,共11页
Bulletin of Geological Science and Technology
关键词
大足石刻
砂岩
毛细水
孔隙
盐害
迁移
Dazu Stone Carvings
sandstone
capillary water
ore
salt damage
migration
