摘要
随着中国建设工程不断向西南地区发展,一系列地质灾害问题日益凸显,许多学者利用InSAR遥感技术在该地区开展早期识别研究卓有成效,但研究却仅限于地表宏观形变的识别与判定,无法明确斜坡内部破裂与表层宏观形变间的对应关系。加之西南地区复杂地质构造作用,产生了许多高隐蔽、难预测的反倾层状岩质边坡,使得InSAR遥感早期识别遇到了又一难题。因此,本文通过开展大型土工离心试验,分析斜坡弯曲-倾倒变形阶段,结合图像分析技术,建立起斜坡倾倒变形模式与表层宏观形变特征之间的耦合关系,并利用原型边坡的InSAR解译和实地调查结果,反向推断边坡所处阶段,将斜坡变形阶段可视化,为此类斜坡变形的识别和防控提供技术支撑。研究表明:1)反倾层状岩质边坡弯曲倾倒破坏主要分为初始蠕变、坡脚倾倒-弯曲、变形累进以及折断带贯通4个阶段。倾倒破坏往往始于坡脚,而后向斜坡中上部发展,伴随阶梯状破裂面的发育贯通,斜坡被整体破坏;2)对试验图像识别分析,获取深部与表层的速率变化,建立二者的对应耦合关系。发现在倾倒变形不同阶段,大变形区域(表层关键裂缝)遵循从下至上的发展规律,依次是坡脚附近—坡前中部—陡缓交界处;且陡缓交界处岩板的变形速率曲线在倾倒变形启动、内部折断带贯通阶段存在两次明显的峰值现象;3)选用扎永变形体的In-SAR解译结果与试验结果进行对照,并通过现场复核,初步判断该变形体正处于变形累进阶段。
Due to the continuous development of construction projects in China's southwest region,geological disaster issues have become increasingly prominent.Many scholars have employed InSAR remote sensing technology to conduct early identification research in the region.The results are fruitful;however,the research is primarily focused on identifying and determining surface macroscopic deformation.The corresponding relationship between slope internal rupture and surface macroscopic deformation remains unclear.Given the complex geological structure in southwest China,many highly concealed and unpredictable anti-dip layered rock slopes have emerged,posing another challenge for the early identification capabilities of InSAR remote sensing.Hence,this study analyzes the bending-toppling deformation stage of slopes by conducting large-scale geotechnical centrifuge tests.It establishes a coupling relationship between the slope toppling deformation mode and the surface macroscopic deformation characteristics by integrating image analysis technology.The InSAR interpretation and field survey results of the prototype slope are utilized to infer the slope stage reversely,visualizing the slope deformation stage to provide technical support for identifying,preventing,and controlling such slopes.The research shows that:1)The bending and toppling failure of anti-dip layered rock slopes mainly occurs in four stages:initial creep,toppling-bending,progressive deformation,and fracture zone penetration.Damage typically initiates at the foot of the slope and progressively develops upward.With the development of the stepped fracture surface,the slope experiences comprehensive destruction.2)Analysis of test image recognition yields rate changes in the deep and surface layers,establishing a corresponding coupling relationship between the two.In different stages of toppling deformation,the large deformation area(surface key cracks)adheres to a developmental law progressing from bottom to top,specifically from the toe of the slope to the middle of the slope to the steep and gentle junction.Two significant peaks in the rate curve of the rock plate at the steep and gentle junction are observed during the onset of toppling deformation and the penetration of the internal fracture zone.3)The InSAR interpretation results of the Zhayong deformation body are compared to the experimental conclusions,and through on-site reviews,it is preliminarily concluded that the deformation body is in the progressive stage of deformation.
作者
陈明浩
郑光
刘震东
刘俊杰
陆会燕
CHEN Minghao;ZHENG Guang;LIU Zhendong;LIU Junjie;LU Huiyan(State Key Lab.of Geohazard Prevention and Geoenvironmental Protection(Chengdu Univ.of Technol.),Chengdu 610059,China;School of Environment and Civil Eng.,Chengdu Univ.of Technol.,Chengdu 610059,China)
出处
《工程科学与技术》
EI
CAS
CSCD
北大核心
2024年第5期60-73,共14页
Advanced Engineering Sciences
基金
国家重点研发计划项目(2021YFC3000401-1)。
关键词
反倾层状岩质边坡
离心模型试验
早期识别
宏观形变特征
anti-dip stratiform rocky slope
centrifuge model test
early identification
macroscopic deformation characteristics
