粗粒组对细粒类填土力学性质的影响分析
|
摘要
粗粒组含量、粗粒粒径对细粒类填土应力-应变特性及抗剪强度具有重要影响。通过单变量原位大面积剪切试验分析了不同粗粒组含量下细粒类填土的应力-应变特性和抗剪强度,并对原位测试土体进行室内试验的颗粒分析,进而分析粒径对细粒类填土的抗剪强度和应力-应变特性的影响规律。试验结果分析表明:土样的峰值剪应力与粗粒组含量呈正相关关系,当试样颗粒限定粒径d_(60)在0.020～0.050 mm时,随着颗粒限定粒径的增大土体的峰值强度和内摩擦角φ增大,而粘聚力c缓慢减小;当颗粒粒径d_(60)大于0.050 mm,随着颗粒限定粒径的增大,土体的峰值强度和内摩擦角φ增大幅度、粘聚力c减小幅度均加大。
The content of coarse grained soils and their grain sizes have an important influence on the stress-strain characteristics of fined grained soil mixtures. This paper presents the valuation influence of coarse grain content on the geotechnical properties of fine grained soil mixtures throughout large scale in-situ direct shear tests. After each test, the grain size distribution of each serious of sample were laboratory tested. The results indicate that: The peak shear strength value is proportional to the content of coarse grained materials. When the grain size range D_(60) is limited within 0.02 to 0.05 mm, both the shear strength and internal friction angle increase with the increase of grain size; when the grain size D60 is greater than 0.05mm, with the increase of grain size, both the rate of internal friction angle increase and the apparent cohesion reduction rate increase.
The content of coarse grained soils and their grain sizes have an important influence on the stress-strain characteristics of fined grained soil mixtures. This paper presents the valuation influence of coarse grain content on the geotechnical properties of fine grained soil mixtures throughout large scale in-situ direct shear tests. After each test, the grain size distribution of each serious of sample were laboratory tested. The results indicate that: The peak shear strength value is proportional to the content of coarse grained materials. When the grain size range D_(60) is limited within 0.02 to 0.05 mm, both the shear strength and internal friction angle increase with the increase of grain size; when the grain size D60 is greater than 0.05mm, with the increase of grain size, both the rate of internal friction angle increase and the apparent cohesion reduction rate increase.
引文
[1] 土的工程分类标准(GB/T 50145—2007)[S].北京:中国计划出版社,2008.
[2] 徐惠,范明桥.中国细颗粒土的统一分类体系初步研究[J].岩土工程学报,2013,35(12):2317-2321.
[3] 徐肖峰,魏厚振,孟庆山,等.粗粒含量对砾类土直剪过程中强度与变形特性影响的离散元模拟研究[J].工程地质学报,2013,21(2):311-316.
[4] 刘松玉,童立元,邱钰,等.煤矸石颗粒破碎及其对工程力学特性影响研究[J].岩土工程学报,2005,27(5):505-510.
[5] 魏厚振,汪稔,胡明鉴,等.蒋家沟砾石土不同粗粒含量直剪强度特征[J].岩土力学,2008,29(1):48-51.
[6] 王光进,杨春和,张超,等.粗粒含量对散体岩土颗粒破碎及强度特性试验研究[J].岩土力学,2009,30(12):3649-3654.
[7] 刘建坤,于钱米,刘景宇,等.细粒土不均匀分布对粗粒土力学特性的影响[J].岩土工程学报,2017,39(3):562-572.
[8] 李沛.土体原位大剪试验研究[J].工程勘察,1981(3).
[9] 张茂省,胡炜,朱立峰,等.饱和土体原位大型剪切试验方法与实践[J].地质通报,2013,32(6):919-924.
[10] 黄志全,吴林峰,王安明,等.基于原位剪切试验的膨胀土边坡稳定性研究[J].岩土力学,2008,29(7):1764-1768.
[11] 杨果林,滕珂,谢兰芳.膨胀土强度的室内直剪和原位推剪对比试验研究[J].中南大学学报:自然科学版,2014(6):1952-1959.
[12] 土工试验方法标准(GB/T 50123—1999)[S].
[2] 徐惠,范明桥.中国细颗粒土的统一分类体系初步研究[J].岩土工程学报,2013,35(12):2317-2321.
[3] 徐肖峰,魏厚振,孟庆山,等.粗粒含量对砾类土直剪过程中强度与变形特性影响的离散元模拟研究[J].工程地质学报,2013,21(2):311-316.
[4] 刘松玉,童立元,邱钰,等.煤矸石颗粒破碎及其对工程力学特性影响研究[J].岩土工程学报,2005,27(5):505-510.
[5] 魏厚振,汪稔,胡明鉴,等.蒋家沟砾石土不同粗粒含量直剪强度特征[J].岩土力学,2008,29(1):48-51.
[6] 王光进,杨春和,张超,等.粗粒含量对散体岩土颗粒破碎及强度特性试验研究[J].岩土力学,2009,30(12):3649-3654.
[7] 刘建坤,于钱米,刘景宇,等.细粒土不均匀分布对粗粒土力学特性的影响[J].岩土工程学报,2017,39(3):562-572.
[8] 李沛.土体原位大剪试验研究[J].工程勘察,1981(3).
[9] 张茂省,胡炜,朱立峰,等.饱和土体原位大型剪切试验方法与实践[J].地质通报,2013,32(6):919-924.
[10] 黄志全,吴林峰,王安明,等.基于原位剪切试验的膨胀土边坡稳定性研究[J].岩土力学,2008,29(7):1764-1768.
[11] 杨果林,滕珂,谢兰芳.膨胀土强度的室内直剪和原位推剪对比试验研究[J].中南大学学报:自然科学版,2014(6):1952-1959.
[12] 土工试验方法标准(GB/T 50123—1999)[S].