干湿循环条件下秸秆灰渣改良膨胀土试验研究
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摘要
膨胀土是遇水较为敏感的特殊土,所以研究膨胀土在干湿循环条件下的抗剪强度特征非常重要,尤其是对改良膨胀土的研究更有实际的工程意义。通过室内直接剪切试验,研究了膨胀土及秸秆灰渣改良土的抗剪强度特征。试验证明,膨胀土的抗剪强度随着灰渣含量的增加而增加,在灰渣含量为17%时强度及黏聚力达到最大值;而改良土的内摩擦角随着灰渣含量的增加而增加,同时改良土强度随着竖向力及养护龄期的增加而线性提高;干湿循环试验证明,膨胀土随着秸秆灰渣含量的增加抗剪强度衰减程度逐渐减小,试样的抗剪强度在第1次干湿循环时衰减较大;4次干湿循环后膨胀土黏聚力从37.0kpa,衰减到4.0 k Pa,内摩擦角衰减范围是28.3~11.64,17%秸秆灰渣改良土黏聚力衰减范围是74.16~57.43,内摩擦角衰减范围是46.05~42.25;直接剪切试验表明17%秸秆灰渣改良土为最佳配比。
Expansive soil is a special soil that is sensitive to water. Therefore,it is very important to study the shear strength characteristics of expansive soil under dry-wet cycle circulation conditions,it has practical engineering significance especially for the study of improved expansive soil. Through indoor direct shear test,the shear strength characteristics of expansive soil and improved soil with straw ash were studied. The test proves that the shear strength of expansive soil increases with the increase of ash content. When the ash content is 17%,the strength and cohesion force reach the maximum value,while the internal friction angle of the improved soil increases with the ash content. The increase,while the strength of the improved soil increases linearly with the increase of vertical force and curing age; The dry-wet cycle test proves that the degree of shear strength attenuation is gradually reduced with the increase of straw ash content,and the shear strength of the straw ashmple is greatly attenuated during the first dry and wet cycle; After 4 dry and wet cycles,the cohesive force of the expansive soil is reduced from 37. 0 k Pa to 4. 0 k Pa,and the internal friction angle is in the range of 28. 3 to 11. 64. 17% straw ash is used to improve soil cohesion. The force attenuation range is 74. 16 ~ 57. 43,and the internal friction angle attenuation range is 46. 05 ~ 42. 25. Direct shear test showed that 17% straw ash improved soil was the best ratio.
Expansive soil is a special soil that is sensitive to water. Therefore,it is very important to study the shear strength characteristics of expansive soil under dry-wet cycle circulation conditions,it has practical engineering significance especially for the study of improved expansive soil. Through indoor direct shear test,the shear strength characteristics of expansive soil and improved soil with straw ash were studied. The test proves that the shear strength of expansive soil increases with the increase of ash content. When the ash content is 17%,the strength and cohesion force reach the maximum value,while the internal friction angle of the improved soil increases with the ash content. The increase,while the strength of the improved soil increases linearly with the increase of vertical force and curing age; The dry-wet cycle test proves that the degree of shear strength attenuation is gradually reduced with the increase of straw ash content,and the shear strength of the straw ashmple is greatly attenuated during the first dry and wet cycle; After 4 dry and wet cycles,the cohesive force of the expansive soil is reduced from 37. 0 k Pa to 4. 0 k Pa,and the internal friction angle is in the range of 28. 3 to 11. 64. 17% straw ash is used to improve soil cohesion. The force attenuation range is 74. 16 ~ 57. 43,and the internal friction angle attenuation range is 46. 05 ~ 42. 25. Direct shear test showed that 17% straw ash improved soil was the best ratio.
引文
1张涛,刘松玉,蔡国军,等.木质素改良粉土热学与力学特性相关性试验研究[J].岩土工程学报,2015,37(10):76-85Zhang Tao,Liu Songyu,Cai Guojun,et al.Experimental study on relationship between thermal and mechannical properties of treated silt by lignin[J].Chinese Journal of Geotechnical Engineering,2015,37(10):76-85
2 郭爱国,孔令伟,胡明鉴,等.石灰改性膨胀土施工最佳含水率确定方法探讨[J].岩土力学,2007,28(3):517-521Guo Aiguo,Kong Lingwei,Hu Mingjian,et al.On determination of optimum water content of lime-treated expansive soil[J].Rock and Soil Mechanics,2007,28(3):517-521
3 Kumar A,Walla B S,Bajaj A.Influence of fly ash,lime,and polyester fibers on compaction and strength properties of expansive soil[J].Journal of Materials in Civil Engineering,2007,19(3):242-248
4 赵辉,储诚富,郭坤龙,等.铁尾矿砂改良膨胀土基本工程性质试验研究[J].土木建筑与环境工程,2017,6(13):98-104Zhao Hui,Chu Chengfu,Guo Kunlong,et al.Experimental analysis of the basic engineering properties of expansive soils improved by irontailings straw ashnd[J].Journal of Civil,Architectural&Environmental Engineering.2017,6(13):98-104
5 孙树林,郑青海,唐俊.碱渣改良膨胀土室内试验研究[J].岩土力学,2012,33(6):1608-1612Sun Shulin,Zheng Qinghai,Tang Jun.Experimental research on expansive soil improved by soda residue[J].Rock and Soil Mechanics,2012,33(6):1608-1612
6 张德恒,孙树林,徐奋强.秸秆灰渣-大理石灰改良膨胀土试验[J].辽宁工程技术大学学报(自然科学版),2014,33(2):193-197Zhang Deheng,Sun Shulin,Xu Fenqiang.Experiment improvement of expansive soil with straw ash-marble dust[J].Journal of Liaoning Technical University(Natural Science),2014,33(2):193-197
7 Bell Fg.Lime stabilization of clay minerals and soils[J].Engineering Geology,1996,42(1-2):223-237
8 张德恒,孙树林,徐奋强.秸秆灰渣改良膨胀土三维膨胀特性试验研究[J].长江科学院院报,2014,31(10):128-133Zhang Deheng,Sun Shulin,Xu Fenqiang.Experimental Research on Three-dimensional Swelling Characteristics of Expansive Soil Improved with strew ash[J].Journal of Yangtze River Scientific Research Institute,2014,31(10):128-133
9 交通部公路科学研究院.公路土工试验规程:JTG E40—2007[S].北京:人民交通出版社,2007Highway Sciences Academy of Communications Ministry.Highway geotechnical test procedures:JTG E40—2007[S].Beijing:China Communication Press,2007
10 Kumar B R P,Sharma R S.Effect of Biomass ash on engineering properties of expansive soils[J].Journal of Geotechnical and Geoenvironmental Engineering,ASCE,2004,130(7):764-767
11 Lees G,Abdelkader M O,Hamdani S K.Effect of the clay fraction on some mechanical properties of lime-soil mixtures[J].Highway Engineer,1982,11(1):3-9
12 Bell F G.Lime stabilization of clay minerals and soils[J].Engineering Geology,1996,42(1-2):223-237
2 郭爱国,孔令伟,胡明鉴,等.石灰改性膨胀土施工最佳含水率确定方法探讨[J].岩土力学,2007,28(3):517-521Guo Aiguo,Kong Lingwei,Hu Mingjian,et al.On determination of optimum water content of lime-treated expansive soil[J].Rock and Soil Mechanics,2007,28(3):517-521
3 Kumar A,Walla B S,Bajaj A.Influence of fly ash,lime,and polyester fibers on compaction and strength properties of expansive soil[J].Journal of Materials in Civil Engineering,2007,19(3):242-248
4 赵辉,储诚富,郭坤龙,等.铁尾矿砂改良膨胀土基本工程性质试验研究[J].土木建筑与环境工程,2017,6(13):98-104Zhao Hui,Chu Chengfu,Guo Kunlong,et al.Experimental analysis of the basic engineering properties of expansive soils improved by irontailings straw ashnd[J].Journal of Civil,Architectural&Environmental Engineering.2017,6(13):98-104
5 孙树林,郑青海,唐俊.碱渣改良膨胀土室内试验研究[J].岩土力学,2012,33(6):1608-1612Sun Shulin,Zheng Qinghai,Tang Jun.Experimental research on expansive soil improved by soda residue[J].Rock and Soil Mechanics,2012,33(6):1608-1612
6 张德恒,孙树林,徐奋强.秸秆灰渣-大理石灰改良膨胀土试验[J].辽宁工程技术大学学报(自然科学版),2014,33(2):193-197Zhang Deheng,Sun Shulin,Xu Fenqiang.Experiment improvement of expansive soil with straw ash-marble dust[J].Journal of Liaoning Technical University(Natural Science),2014,33(2):193-197
7 Bell Fg.Lime stabilization of clay minerals and soils[J].Engineering Geology,1996,42(1-2):223-237
8 张德恒,孙树林,徐奋强.秸秆灰渣改良膨胀土三维膨胀特性试验研究[J].长江科学院院报,2014,31(10):128-133Zhang Deheng,Sun Shulin,Xu Fenqiang.Experimental Research on Three-dimensional Swelling Characteristics of Expansive Soil Improved with strew ash[J].Journal of Yangtze River Scientific Research Institute,2014,31(10):128-133
9 交通部公路科学研究院.公路土工试验规程:JTG E40—2007[S].北京:人民交通出版社,2007Highway Sciences Academy of Communications Ministry.Highway geotechnical test procedures:JTG E40—2007[S].Beijing:China Communication Press,2007
10 Kumar B R P,Sharma R S.Effect of Biomass ash on engineering properties of expansive soils[J].Journal of Geotechnical and Geoenvironmental Engineering,ASCE,2004,130(7):764-767
11 Lees G,Abdelkader M O,Hamdani S K.Effect of the clay fraction on some mechanical properties of lime-soil mixtures[J].Highway Engineer,1982,11(1):3-9
12 Bell F G.Lime stabilization of clay minerals and soils[J].Engineering Geology,1996,42(1-2):223-237