摘要
崩塌是石质山区主要的地质灾害,崩塌源通常存在稳定性较低的大量危岩体,其形成机制是防治崩塌灾害的关键环节。现场调查发现,四面山国家级风景名胜区红岩山崩塌源的危岩可分为坠落式危岩、倾倒式危岩、座滑式危岩和扶壁式危岩4类,所占比例分别为70%、15%、8%和7%;具有4级陡崖的地形特征、硬质砂岩和软质泥岩交互沉积、近于正交的3组岩体结构面是红岩山崩塌灾害孕发的主要环境地质条件;根据现场观测,岩腔后侧壁泥岩压裂风化速度5.2cm/a左右,是斜坡表面裸露泥岩气候风化速度的3～6倍,岩腔的形成过程是崩塌灾害演绎的起搏器;运用地貌学方法揭示了红岩山崩塌灾害链式演化规律,当岩腔深度超过3m后,岩腔顶部的危岩块易于发生崩塌。
Collapse is the dominant geological disaster in rocky mountain area,and usually many individual-perilous rock or bulk-perilous rocks exist in the source of collapse.The formation mechanism of perilous rock is one key link for hazard mitigation of collapse.According to the field investigation,four types of perilous rock at the source of Mt.Hongyan in the national scenic spots of Simianshan are classified as the falling perilous rock,the toppling perilous rock,the sliding perilous rock and the counterfort perilous rock,with the percentage of 70%,15%,8% and 7%,respectively.The general geological conditions to trigger the collapse disasters in the Mt.Hongyan are concluded aslandforms with four cliffs,rock composite with sandstone and mudstone alternatively,and three sets of rockmass structure planes with the orthography.Field observations have identified the pacemaker of rock cells in mudstone below cliff,the weathering velocity of mudstone in rockcell under pressure is about 5.2 cm/a,2 ～6 times exposing in air.Further,based on the geomorphology the chained principle for the developing of collapse in Mt.Hongyan is revealed.The result shows that collapses are easy to take place when the length of rock cell is over 3 m.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
北大核心
2010年第3期1-6,共6页
Journal of Sichuan University (Engineering Science Edition)
基金
国家自然科学基金资助项目(50678182)
重庆市重点自然科学基金资助项目(2008BA0015)
关键词
崩塌灾害
基座压裂破坏
链式规律
崩塌源
危岩
红岩山
collapse disaster
base rupture under pressure
chained principle
sourse of collapse
perilous rock
Mt.Hongyan
