兰州Q_4黄土力学性质的各向异性初探
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摘要
采用室内固结和直剪试验方法,对兰州Q4黄土分别在水平向和垂直向进行了压缩性、抗剪强度和变形参数的比较研究,以期说明取样的方向性对黄土力学性质的影响.研究结果表明:兰州Q4黄土力学性质呈现较为显著的各向异性,在法向应力较低时,显得尤为明显,随法向应力增高,差异性相对减小.对承受垂直向荷载的地基基础等工程类型而言,用垂直向试样所获得的试验值是合理且偏于安全的,但对于边坡和隧道与地下结构等工程,则应考虑黄土强度参数和变形参数的各向异性.
The laboratory consolidation and direct shear tests were carried out to compare the shear strength parameters and deformation parameters of Q4 loess in Lanzhou from horizontal and vertical direction respectively,so as to explain the directivity effect on the mechanical properties of the loess.The results show that the anisotropy of mechanical properties of Q4 loess in Lanzhou is remarkable,especially when the normal stress is lower,but when the normal stress is getting higher,the relative differences between vertical and horizontal samplings are reduced.This has something to do with the structural strength in the vertical and horizontal directions of the loess.For the constructions that undergo the vertical loads such as the foundation,subgrade,and et al,the vertical sampling and relevant values are reasonable and safe,but for the slope,tunnel construction and underground structures,the anisotropy or directivity effect of loess should be carefully considered.
The laboratory consolidation and direct shear tests were carried out to compare the shear strength parameters and deformation parameters of Q4 loess in Lanzhou from horizontal and vertical direction respectively,so as to explain the directivity effect on the mechanical properties of the loess.The results show that the anisotropy of mechanical properties of Q4 loess in Lanzhou is remarkable,especially when the normal stress is lower,but when the normal stress is getting higher,the relative differences between vertical and horizontal samplings are reduced.This has something to do with the structural strength in the vertical and horizontal directions of the loess.For the constructions that undergo the vertical loads such as the foundation,subgrade,and et al,the vertical sampling and relevant values are reasonable and safe,but for the slope,tunnel construction and underground structures,the anisotropy or directivity effect of loess should be carefully considered.
引文
[1]谢定义.试论我国黄土力学研究中的若干新趋向[J].岩土工程学报,2001,23(1):3-13.
[2]中国科学院土木建筑研究所土力学研究室.黄土基本性质的研究[C].北京:科学出版社,1961.
[3]王永焱,林在贯.中国黄土的结构特征及物理力学性质[M].北京:科学出版社,1990.
[4]齐吉琳,谢定义,石玉成.土结构性的研究方法及现状[J].西北地震学报,2001,23(1):9-103.
[5]谢定义,齐吉琳,朱元林.土的结构性参数及其与变形强度的关系[J].水利学报,1999(10):1-6.
[6]邵生俊,周飞飞,龙吉勇.原状黄土结构性及其定量化参数研究[J].岩土工程学报,2004,26(4):531-536.
[7]邵生俊,邓国华.原状黄土的结构性强度特性及其在黄土隧道围岩压力分析中的应用[J].土木工程学报,2008,41(11):93-98.
[8]龚晓南.高等土力学[M].杭州:浙江大学出版社,1996.
[9]陈仲颐,周景星,王洪?.土力学[M].北京:清华大学出版社,2001.
[10]蒋彭年.土的本构关系[M].北京:科学出版社,1982.
[2]中国科学院土木建筑研究所土力学研究室.黄土基本性质的研究[C].北京:科学出版社,1961.
[3]王永焱,林在贯.中国黄土的结构特征及物理力学性质[M].北京:科学出版社,1990.
[4]齐吉琳,谢定义,石玉成.土结构性的研究方法及现状[J].西北地震学报,2001,23(1):9-103.
[5]谢定义,齐吉琳,朱元林.土的结构性参数及其与变形强度的关系[J].水利学报,1999(10):1-6.
[6]邵生俊,周飞飞,龙吉勇.原状黄土结构性及其定量化参数研究[J].岩土工程学报,2004,26(4):531-536.
[7]邵生俊,邓国华.原状黄土的结构性强度特性及其在黄土隧道围岩压力分析中的应用[J].土木工程学报,2008,41(11):93-98.
[8]龚晓南.高等土力学[M].杭州:浙江大学出版社,1996.
[9]陈仲颐,周景星,王洪?.土力学[M].北京:清华大学出版社,2001.
[10]蒋彭年.土的本构关系[M].北京:科学出版社,1982.
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