摘要
为研究强风化岩在不同应力状态下的力学特征,以赤峰地区大东北商业项目为研究背景,运用室内岩石薄片显微镜方法定量分析了场区玄武岩的风化程度,并运用室内三轴试验方法,研究了强风化玄武岩的应力应变特征,分析不同围压条件下抗压强度、应变、弹性模量的变化规律。结果表明,全风化玄武岩中长石和辉石的蚀变指数变化范围为4~5,强风化玄武岩中长石和辉石的蚀变指数变化范围为3~4;不同围压条件下强风化玄武岩的应力应变变化规律大致相同,可以划分为I阶段~IV阶4个阶段,分别为I阶段为裂隙压密阶段、II阶段为弹性变形阶段、III阶段为非稳定破裂发展阶段和IV阶段为失稳破坏阶段;随着围压的增加,强风化玄武岩的峰值应变、峰值偏应力均呈线性增加的趋势,而弹性模量呈线性减小的趋势。
In order to study the mechanical characteristics of strongly weathered rock under different stress states,the indoor rock thin section microscope method was used to quantitatively analyze the weathering degree of the basalt in the site,with the background of the Chifeng Dadongbei commercial project.The stress-strain characteristics of strongly weathered basalt were studied using indoor triaxial testing methods,and the changes in compressive strength,strain,elastic modulus under different confining pressure conditions were analyzed.The results indicate that the alteration index of feldspar and pyroxene in fully weathered basalt ranges from 4 to 5,while the alteration index of feldspar and pyroxene in strongly weathered basalt ranges from 3 to 4;The stress-strain changes of strongly weathered basalt under different confining pressures are roughly the same,which can be divided into four stages:stage I to stage IV,namely stage I for crack compaction,stage II for elastic deformation,stage III for unstable fracture development,and stage IV for unstable failure;With the increase of confining pressure,the peak strain and peak deviator stress of strongly weathered basalt show a linear increase trend,while the elastic modulus shows a linear decrease trend.
作者
孙亮亮
于宏波
徐鑫磊
Sun Liangliang;Yu Hongbo;Xu Xinlei(Chifeng Haolin Engineering Survey and Design Co.,Ltd.,Chifeng,China)
出处
《科学技术创新》
2023年第26期43-46,共4页
Scientific and Technological Innovation
关键词
赤峰地区
强风化玄武岩
力学特性
弹性模量
蚀变指数
泊松比
峰值偏应力
Chifeng City
strongly weathered basalt
mechanical properties
elastic modulus
erosion index
poisson's ratio
peak deviator stress
