摘要
危岩崩塌是山区主要地质灾害类型及动力地质作用现象,其演绎规律受控于陡崖或陡坡下部岩腔的发育特征。通过对三峡库区2 000余个危岩体的查勘和观测,发现陡崖或陡坡下部岩腔内壁面60%以上的裂隙具有压张性或压剪性,表征泥岩风化具有显著的压裂特点,泥岩压裂风化速度是自然状态下风化速度的2~7倍;运用地貌分析法提出了岩腔后壁平行后退的演化模型,通过有限元数值模拟初步揭示了岩腔后壁顶部竖向位移及脚部压应力随岩腔深度增加而近似线性增大的规律。
Perilous rock collapse is the dominant geological disaster and dynamic geological process in mountain area,and its deductive rules are controlled by the development characteristics of rock cell in cliff or steep slope bottom.Through survey and observation of over 2000 perilous rocks in the Three Gorges Reservoir region,it can be found that more than 60% of cracks on the inner surface of rock cell in cliff or steep slope bottom are characterized by compression-dilatancy or compression-shear,which indicates that the mudstone weathering processes have notable fracturing features and the weathering velocity is 2~7 times faster than that under nature condition.Then a deduction model of parallel recession of rock cells′ back surface is put forward by geomorphologic analysis.We also reveal the rules that the vertical displacement and root compression increase approximately linearly with the increase of depth of rock cell by FEM numerical simulation.
出处
《人民长江》
北大核心
2010年第21期51-54,共4页
Yangtze River
基金
国家自然科学基金项目(50678182)
重庆市重点自然科学基金项目(2008BA0015)
关键词
崩塌灾害
岩腔
压裂风化
平行后退
现场观测与数值模拟
collapse disaster
rock cell
weathering in stress status
parallel recession
field observation and numerical simulation
