武隆县羊角场镇厚层灰岩山体大型危岩体破坏模式及成因机制研究

The Failure Patterns and Their Formation Mechanisms of Large Perilous Rocks in Thick Layered Limestone Masses in Yangjiaochang Town,Wulong County

厚层灰岩山体在我国滇黔渝鄂湘等西南山区分布广泛,研究这类山体的破坏模式和成因机理,是对这类危岩体灾害进行风险评估和工程治理的依据,具有重要的意义。本文以重庆武隆羊角场镇区域内大型危岩体为研究对象,通过现场调查,对危岩体的发育分布特征、破坏类型和形成机制进行分析。结果表明:羊角场镇后山陡崖带上分布有大型危岩体11个,总体积约1280×104 m3;根据危岩体形态、结构面特征、变形迹象,危岩体的破坏模式可划分为视向滑动式、滑塌式、倾倒式和落石破坏式4种类型;控制研究区大型危岩体形成的主要因素有斜坡结构类型、岩性组合、岩体结构、岩溶作用和采矿活动等。

Landslides and collapses on mountain massifs with thick layered limestone masses distribute widely in mountainous area in southwestern China.It is of important significance for risk assessment and prevention to study the failure patterns and their formation mechanisms of this kind geohazards.Based on detail field investigation,the development features,failure patterns and their formation mechanisms of the large perilous rocks in the area of Yangjiaochang Town in Wulong County,Chongqing City are studied in this paper.Main conclusions are as follows：there are 11 large perilous rocks at the abrupt cliff in the Yangjiaochang Town area,with the total volume nearly 1280×104 m3.According to the shapes,features of main structural planes and signs of deformation,the failure patterns can be divided into four types which are apparent dip slide,slide collapse,topple and rockfall;The main influence factors are slope structure,lithological combination,rock mass structure,karstification and mining activities etc.,This study discusses the mechanism affecting formation of the perilous rocks in detail.