冻融循环下须弥山石窟红砂岩劣化试验研究  

Experimental study on the deterioration of red sandstone in Xumishan Grottoes under freeze-thaw cycles

作　　者：廖明可 崔德山[2] 刘煜 杨赫楠 LIAO Mingke;CUI Deshan;LIU Yu;YANG Henan(School of Civil Engineering,Chongqing University,Chongqing 400045,China;Faculty of Engineering,China University of Geosciences(Wuhan),Wuhan 430074,China;POWERCHINA Beijing Engineering Corporation Limited,Beijing 100024,China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]中国地质大学(武汉)工程学院,湖北武汉430074 [3]中国电建集团北京勘察设计研究院有限公司,北京100024

出　　处：《安全与环境工程》2024年第4期142-150,157,共10页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(42277171)。

摘　　要：须弥山石窟处于我国季节性冻土区域,长期的冻融循环条件对岩体造成了很严重的风化损伤。将采自须弥山石窟的红砂岩制备成天然组、60%饱水组和饱水组3组试样进行冻融循环试验,记录冻融循环10、20、40和120次时岩样的物理性质参数,研究冻融循环下砂岩的劣化规律。结果表明:岩样在经过不同的冻融循环次数后质量、体积、硬度和波速整体呈现下降的趋势,且随着冻融次数的增加其下降的趋势逐渐变得平缓;岩样各物理性质参数的劣化率在冻融循环后逐渐增加,前40次冻融循环周期内物理性质参数劣化速率较快,之后随着冻融循环次数的增加其劣化逐渐趋于平缓;在对3组不同含水率的岩样进行相同次数的冻融循环试验后发现,在经过相同的冻融循环次数后,随着含水率的增加岩样物理性质参数劣化更加显著;根据砂岩的质量、体积、波速的劣化率定义了砂岩的累积损伤度,建立了累积损伤度与冻融循环次数的非线性模型,揭示了累积损伤度随冻融循环次数变化的非线性增长规律。该研究成果能够为须弥山石窟的文物保护工作提供科学依据。Xumishan Grottoes are located in the seasonal frozen soil area of China.Long-term freeze-thaw cycles have caused serious weathering of rock mass.Therefore,the red sandstone collected from Xumishan Grottoes were prepared into three groups:natural group,60%saturated group and saturated group for freeze-thaw cycle test.The physical properties of the rock samples were recorded every 10,20,40 and 120 times to study the deterioration pattern of sandstone under freeze-thaw cycles.The results show that the mass,volume,hardness and wave velocity of rock samples show a downward trend after different freeze-thaw cycles,and the downward trend gradually becomes gentle with the increase of freeze-thaw cycles.The deterioration rate of physical properties of rock samples gradually increases after freeze-thaw cycles.The deterioration rate of physical parameters in the first 40 freeze-thaw cycles is faster,and then the deterioration gradually tends to be gentle with the increase of freeze-thaw cycles.Comparing three groups of rock samples with different water contents,it is found that the deterioration rate of physical parameters of rock samples increases after the same number of freeze-thaw cycles.The cumulative damage degree of sandstone is defined based on the deterioration rates of its mass,volume,and wave velocity.A nonlinear model has been established between the cumulative damage degree and the number of freeze-thaw cycles,revealing the nonlinear growth pattern of cumulative damage degree with the increase in freeze-thaw cycles.The research findings can provide a scientific basis for the preservation of cultural relics at Xumishan Grottoes.

关 键 词：须弥山石窟 红砂岩 冻融循环 劣化试验 物理性质参数 累积损伤度 

分 类 号：X43[环境科学与工程—灾害防治]