石窟寺砂岩阶段异质性劣化特征与损伤机制研究  

ON THE PHASE HETEROGENEITY DETERIORATION CHARACTERISTICS AND DAMAGE MECHANISM OF GROTTOES SANDSTONE

作　　者：都奎建 兰恒星 刘世杰[1] 包含 李黎[3] DU Kuijian;LAN Hengxing;LIU Shijie;BAO Han;LI Li(School of Geological Engineering and Geomatics,Chang'an University,Xi'an 710064,China;Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,China;Chinese Academy of Cultural Heritage,Beijing 100029,China;School of Highway,Chang'an University,Xi'an 710064,China)

机构地区：[1]长安大学地质工程与测绘学院,西安710064 [2]中国科学院地理科学与资源研究所,资源与环境信息系统国家重点实验室,北京100101 [3]中国文化遗产研究院,北京100029 [4]长安大学公路学院,西安710064

出　　处：《工程地质学报》2024年第6期1951-1962,共12页Journal of Engineering Geology

基　　金：国家重点研发计划项目(资助号:2019YFC1520601);国家自然科学基金项目(资助号:42041006,41927806)。

摘　　要：砂岩是我国石窟寺最常见的赋存岩石类型,其本身疏松多孔,易发生强烈的水-岩溶蚀作用,严重威胁着石窟寺岩体的稳定性及宝贵的艺术价值。本文通过室内干湿循环模拟试验,从宏观力学与微观结构方面研究了水-岩溶蚀条件下安岳石窟砂岩的劣化损伤规律,探讨了石窟寺砂岩的阶段异质性劣化特征与损伤机制。研究发现:质量、波速、强度等岩石基本物性指标均随干湿循环进行而逐渐劣化;孔隙变化、微观形貌变化、矿物含量变化具有阶段性劣化特征,是决定砂岩阶段异质性劣化效应的3个关键因素。劣化损伤可分为3个阶段:以孔隙扩展主控的第1阶段、以微观接触结构损伤主控的第2阶段、以穿晶破裂主控的第3阶段。基于干湿循环作用下砂岩的阶段异质性劣化特征与损伤规律,本文进一步建立了砂岩劣化损伤演化模型,并针对性地提出了石窟寺岩体修护建议,可为长期处于水-岩溶蚀条件下的石窟寺岩体保护提供一定的理论依据。Sandstone is the most common rock type of grottoes in China.It is loose,porous,and prone to strong water rock dissolutions,which seriously threatens the stability of the rock mass of grotto temples and valuable artistic values.In this paper,the damage law under the condition of water rock dissolution of the sandstone in the AnYue Grottoes is studied in both macro-mechanical and micro-structural aspects through laboratory dry-wet cycle simulation tests,and the phase heterogeneity deterioration characteristics and damage mechanism of grottoes sandstone are discussed.It is found that the basic physical property indices of rock such as quality,wave velocity and strength all gradually deteriorate with the proceeding of dry-wet cycles.The changes of pores,micro morphologies and mineral contents are characterized by phase degradations,which are the three key factors determining the phase heterogeneity degradation effect of sandstones.The degradation damage can be divided into three phases:the first phase dominated by pore expansion,the second phase dominated by micro contact relationship damage and the third phase dominated by transgranular fracture.Based on the phase heterogeneity deterioration characteristics and damage law of sandstone under dry-wet cycles,this paper further proposes a deterioration damage evolution model of sandstones,and gives targeted suggestions for the repair of grottoes rock mass,which to some extent provides a theoretical basis for the protection of grottoes rock mass affected by long-time water rock dissolutions.

关 键 词：岩石力学 石窟砂岩 干湿循环 阶段性劣化 损伤机制 

分 类 号：P642.3[天文地球—工程地质学]