摘要
灰岩地层具有较好的可靠性和适宜性,并具有较大的各向异性,其分布从大的溶洞、管道、断裂到小的溶蚀裂隙、孔洞等,前者在工程探测及处理措施方面研究已较为成熟,笔者针对溶蚀孔、隙型灰岩的力学参数取值进行了研究,得到了如下结论:溶蚀孔、隙型灰岩岩石抗压强度与孔隙率存在较好的幂函数关系,幂常量接近于-0.5,即y=ax^(-0.5),其系数a代表了孔隙率为1%时的岩石抗压强度;基于Hoek-Brown强度准则及岩体孔隙率n,建立岩体参数m_(b)、S、a与孔隙率n的关系式,并通过孔隙率来描述岩体力学参数(岩体抗压强度R_(cm)、岩体抗拉强度R_(tm)、岩体抗剪强度参数c_(m)和φ_(m)),简化了通过量化GSI进行力学参数取值的复杂性,避免了量化GSI的主观性和不确定性,在溶蚀孔、隙型灰岩地层具有较好的可靠性和适宜性,对同类场区的工程建设具有一定的指导意义。
The limestone stratum has better reliability and suitability, which has certain guiding significances to the engineering construction of similar fields. Limestone stratum has great anisotropy and large karst caves, pipelines, faults to small dissolution cracks and voids are distributed in limestone. The anisotropy is relatively maturing in engineering exploration and treatment. The mechanical parameters, namely solution pore & crevice limestone were studied, and the following conclusions were drawn. There is a good power function relationship between compressive strength and porosity of solution pore and crevice limestone. The power constant is close to-0.5, the formula is y=ax^(-0.5), and its coefficient represents the compressive strength of rock with 1% porosity. Based on Hoek-Brown strength criterion and rock mass porosity n, the relationship between rock mass parameters m_(b), S, a and porosity n is established, and rock mass mechanical parameters(compressive strength R_(cm), tensile strength R_(tm), shear strength parameters c_(m) and φ_(m)of rock mass) are described by porosity. It simplifies the complexity of mechanical parameters selection by quantifying GSI, and avoids subjectivity and uncertainty of quantifying GSI, and it has good reliability and suitability in pore and crevice limestone stratum. The study has certain guiding significance for the construction of similar sites.
作者
胡政
郑克勋
郭维祥
刘金洋
田茂中
Hu Zheng;Zheng Kexun;Guo Weixiang;Liu Jinyang;Tian Maozhong(Power China Guiyang Engineering Corporation Ltd.,Guiyang 550081,P.R.China;Guizhou BIM Engineering and Technology Research Center,Guiyang 550081,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2022年第2期421-427,共7页
Chinese Journal of Underground Space and Engineering
基金
中国水电工程顾问集团公司科技项目(GW—KJ—2013—08)
贵州省科技计划项目(黔科合平台人才[2019]5301号)。
关键词
溶蚀孔
隙型灰岩
室内试验
孔隙率
力学参数
solution pore
crevice limestone
laboratory test
porosity
mechanical parameters
