庆阳北石窟寺濒危岩体变形特征分析  

Deformation characteristics of dangerous rock masses in the North Grotto Temple,Qingyang City

作　　者：马雪雅 张理想 陈银桥 张景科[1,2] 邹红宇 谷留杨 MA Xueya;ZHANG Lixiang;CHEN Yinqiao;ZHANG Jingke;ZOU Hongyu;GU Liuyang(College of Civil Engineering and Mechanics,Lanzhou University,Lanzhou 730000,Gansu,China;Key Laboratory of Mechanics on Disaster and Environment in Western China,Ministry of Education of China,Lanzhou University,Lanzhou 730000,Gansu,China)

机构地区：[1]兰州大学土木工程与力学学院,甘肃兰州730000 [2]兰州大学西部灾害与环境力学教育部重点实验室,甘肃兰州730000

出　　处：《地震工程学报》2023年第5期1145-1155,共11页China Earthquake Engineering Journal

基　　金：国家重点研发计划项目(2019YFC1520600)。

摘　　要：危岩体发育会对石窟寺的稳定和游客安全造成威胁,利用变形监测分析石窟濒危岩体变形特征对岩体稳定性评估起重要作用。文章以甘肃庆阳北石窟寺为例,采用全球导航卫星系统(Global Navigation Satellite System, GNSS)变形监测、测缝计和非接触式裂隙监测等技术,从北石窟寺分布区域地质体、石窟赋存崖体和洞窟关键块体三个尺度研究濒危岩体的变形特征。监测周期内,区域地质体上部位移呈突发性变化,连续降雨后产生5.2 mm的沉降,中部基岩出露部位位移遵循先缓慢增长后逐渐恢复的变化规律,变形量维持在±1 mm以内。崖体内构造裂隙底部变形量呈波动式上升,于次年1—2月达到全年最高值,且随着温度降低,裂隙中部变形速率大于底部。32窟内浅表性裂隙变形量在0 mm附近±2 mm范围内持续波动,无进一步扩张或闭合趋势。区域地质体变形与降雨有高度相关性,崖体变形与温度呈强烈负相关,洞窟关键块体变形也易受温湿度和人为扰动影响。目前三个尺度的岩体变形量均在小范围内变化,相互之间影响较小,无协同性。对濒危岩体变形特征的分析可为北石窟寺稳定性评估和预测分析工作提供数据参考。Grotto stability and visitor safety are threatened by the development of dangerous rock mass.Monitoring and analysis of the deformation characteristics of dangerous rock mass in grottoes play a crucial role in the stability assessment of rock mass.Considering the North Grotto Temple in Qingyang,Gansu Province,as the example,Global Navigation Satellite System deformation monitoring,joint meter,and noncontact fissure monitoring techniques were applied for analysis of the deformation characteristics of dangerous rock mass in three scales,namely,the regional geological body,cliff body,and key blocks of the North Grotto Temple.During the monitoring period,the displacement of the upper regional geological body presented a sudden change,with a settlement of 5.2 mm after continuous rainfall,the displacement of the central bedrock recovered gradually after a slow growth,and the deformation was within±1 mm.The deformation at the bottom of tectonic fissures in cliff increased in fluctuating form,with the highest value in January—February of the following year.With decreasing temperature,the deformation rate in the middle of the fissure was quicker than that at the bottom.The deformation of superficial fissures in cave 32 fluctuated near 0 mm in the range of±2 mm.Deformation of the regional geological body was highly correlated with rainfall,and that of the cliff was negatively correlated with temperature;moreover,the deformation of key blocks was also susceptible to temperature,humidity,and human disturbance.Current deformations of the rock masses at the three scales varied within a small range,with little influence on each other and no synergy.This study can provide reference data for the stability assessment and predictive analysis of the North Grotto Temple.

关 键 词：北石窟寺 濒危岩体 变形监测 裂隙监测 岩体变形特征 

分 类 号：K879.2[历史地理—考古学及博物馆学] P631.24[历史地理—历史学]