顾及形变信息的青藏铁路工程走廊融沉风险评估  

Risk Assessment of Permafrost Thawing along Qinghai-Tibet Engineering Corridor Integration Ground Deformation

作　　者：张正加 林洪 陈富龙 冯晓帆 王猛猛 刘修国[1] ZHANG Zhengjia;LIN Hong;CHEN Fulong;FENG Xiaofan;WANG Mengmeng;LIU Xiuguo(School of Geography and Information Engineering,China University of Geosciences(Wuhan),Wuhan 430078,China;Fujian Institute of Scientific and Technological Information,Fuzhou 350003 China;Fujian Key Laboratory of Information and Network,Fuzhou 350003,China;International Research Center of Big Data for Sustainable Development Goals,Beijing 100094,China;Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China)

机构地区：[1]中国地质大学(武汉)地理与信息工程学院,武汉430078 [2]福建省科学技术信息研究所,福州350003 [3]福建省信息网络重点实验室,福州350003 [4]可持续发展大数据国际研究中心,北京100094 [5]中国科学院空天信息创新研究院,北京100094

出　　处：《地球信息科学学报》2024年第11期2552-2566,共15页Journal of Geo-information Science

基　　金：国家自然科学基金项目(41801348)。

摘　　要：在全球气候变暖和人类活动的共同作用下,青藏铁路工程走廊内的多年冻土发生了严重退化,对人类安全、生态环境和多年冻土工程设施的安全构成了威胁。因此,对青藏铁路工程走廊沿线多年冻土融沉风险进行评估是当务之急。由于现有的冻土融沉风险评估指数大多是静态的,未考虑地表冻融循环过程中的动态性变化,为了准确评估青藏铁路工程走廊的多年冻土融沉风险,本文提出了一种基于层次分析法(Analytic Hierarchy Process, AHP)的多因子指数对青藏铁工程走廊沿线多年冻土融沉危险性进行评估。该指数融合了地面动态形变信息和静态地质灾害评估指数(容许承载力指数、危险区指数和融沉指数),地表形变速率通过小基线干涉测量技术(Small Baseline Subset Interferometric SAR, SBAS-InSAR)获取。实验结果表明,研究区的形变速率范围在-60~43 mm/y,均值为~7 mm/y;所提出的多因子指数评估结果显示青藏铁路工程走廊的多年冻土区以低危险地区为主,占比约60%,高危险地区的比例约为22%,且高危险最集中的地区是楚玛尔河至风火山,其中北麓河区域发生融沉灾害的可能性最大。与传统的地质灾害评估方法相比,所提出的多因子指数方法在形变较大的区域效果较好,如在唐古拉和楚玛尔河地区。研究结果可为其他多年冻土地区的多年冻土工程设计和施工提供有价值的指导。Under the combined influence of global climate warming and human activities,permafrost within the Qinghai-Tibet Engineering Corridor(QTEC)has significantly degraded,posing threats to human safety,the ecological environment,and the secure operation of permafrost engineering facilities.Consequently,it is urgent to assess the risks of permafrost thaw settlement along QTEC.Traditional permafrost settlement assessment indices are mostly static,neglecting dynamic factors.To address this,an Analytic Hierarchy Process(AHP)-based multi-factor assessment index(Im)was proposed in this paper,which integrates ground dynamic deformation data and three geo-hazard indices:the allowable bearing capacity index,the risk zone index,and the settlement index.The SBAS-InSAR technique can overcome atmospheric delay and spatiotemporal decorrelation issues.The allowable bearing capacity index considers MAGT(Mean Annual Ground Temperature)and soil type.The risk zone index incorporates factors such as bare rock,soil properties,ALT(Active Layer Thickness),and VIC(Volumetric Ice Content).The thaw settlement index is based on VIC and∆ALT,with∆ALT derived using the Stefan formula.The allowable bearing capacity index is calculated using a formula based on MAGT and soil type.The risk zone index is determined through hazard zone assessment.The VIC in the thaw settlement index is calculated using MAGT,soil type,NDVI,and slope,while the∆ALT is obtained through the Stefan formula.The evaluation results of the three different geological hazard indices were calculated and analyzed individually,and then compared to the multi-factor analysis results to verify the reliability of the proposed method.The correlation between the geological hazard index and ground deformation was also explored.The ground deformation rate was derived using time-series interferometric SAR(InSAR),ranging from-60 mm/year to 43 mm/year,with an average surface deformation rate of-7 mm/year across the entire study area.The Im results show that the permafrost regions along QTEC

关 键 词：融沉风险 风险评估 层次分析法 多因子指数 多年冻土 青藏铁路工程走廊 地表形变 小基线干涉测量 

分 类 号：U212.2[交通运输工程—道路与铁道工程]