학술논문
岩相学特征对岩石抗压强度影响的试验研究——以新疆花岗岩为例 / Effect of petrographic characteristics on uniaxial compressive strength of granitic rocks from Xinjiang,China
Document Type
Academic Journal
Author
Source
中南大学学报（英文版） / Journal of Central South University. 30(7):2340-2359
Subject
Language
Chinese
ISSN
2095-2899
Abstract
岩相学特征对岩石的力学性质起着决定性作用.为深入研究岩相学特征对岩石抗压强度的影响,并进一步确定影响其抗压强度的关键岩相学指标,定量研究了新疆某引水工程中花岗岩类岩石的岩相学特征,通过相关性分析研究了斜长石含量、钾长石含量、石英含量、暗色矿物含量、结晶程度、平均粒径和粒径分选系数等7个量化指标来研究其对岩石抗压强度的影响.结果表明,花岗岩中暗色矿物含量和结晶程度与其单轴抗压强度无明显的相关性,影响花岗岩类岩石单轴抗压强度的岩相学指标主要包括石英含量、长石含量(两种长石含量之和)、平均粒径和粒径分选系数4种,影响抗压强度的各因素比重排序为:粒径分选系数>长石含量>石英含量>平均粒径.另外,通过对岩石薄片的镜下观察进一步阐明了各岩相学指标对抗压强度的影响机制,并最终认为长石矿物对所研究的花岗岩类岩石的抗压强度起着至关重要的作用,是首要考虑的因素.
The petrographic characteristics of rocks are the determining factors affecting their mechanical properties.This study aims to intensively assess the effect degree of petrographic characteristics of granitic rocks on their uniaxial compressive strength(UCS)and determine the dominant factors affecting the UCS.The quantification of various petrographic parameters and mechanical properties of granitic rocks located in the Altai region of Xinjiang,China,has been carried out.Seven petrographic parameters including plagioclase content,K-feldspar content,quartz content,dark-colored mineral content,crystalline degree,mean grain size and sorting coefficient,were selected to investigate the effect of petrographic characteristics on the UCS of granitic rocks.The detailed analyses of the photomicrographs of the studied samples were used to understand the influence mechanism of each petrographic parameter on the UCS.The results show that the petrographic parameters affecting the UCS mainly include quartz content,feldspar content,mean grain size and sorting coefficient.The proportion order of the petrographic parameters affecting the UCS significantly as follows:sorting coefficient>feldspar content>quartz content>mean grain size,the sorting coefficient of grain size and feldspar content are the dominant factors affecting the UCS of granitic rocks.Ultimately,the feldspar minerals play a critical role in the UCS of the studied granitic rocks and they are the primary consideration when investigating the factors affecting the UCS of granitic rocks.
The petrographic characteristics of rocks are the determining factors affecting their mechanical properties.This study aims to intensively assess the effect degree of petrographic characteristics of granitic rocks on their uniaxial compressive strength(UCS)and determine the dominant factors affecting the UCS.The quantification of various petrographic parameters and mechanical properties of granitic rocks located in the Altai region of Xinjiang,China,has been carried out.Seven petrographic parameters including plagioclase content,K-feldspar content,quartz content,dark-colored mineral content,crystalline degree,mean grain size and sorting coefficient,were selected to investigate the effect of petrographic characteristics on the UCS of granitic rocks.The detailed analyses of the photomicrographs of the studied samples were used to understand the influence mechanism of each petrographic parameter on the UCS.The results show that the petrographic parameters affecting the UCS mainly include quartz content,feldspar content,mean grain size and sorting coefficient.The proportion order of the petrographic parameters affecting the UCS significantly as follows:sorting coefficient>feldspar content>quartz content>mean grain size,the sorting coefficient of grain size and feldspar content are the dominant factors affecting the UCS of granitic rocks.Ultimately,the feldspar minerals play a critical role in the UCS of the studied granitic rocks and they are the primary consideration when investigating the factors affecting the UCS of granitic rocks.