ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS

SONG Zhang; CHENG Qiangong; ZHANG Wei; MENG Fanchao

Volume 15 Issue 5

Apr. 2011

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SONG Zhang, CHENG Qiangong, ZHANG Wei, MENG Fanchao. 2007: ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS. JOURNAL OF ENGINEERING GEOLOGY, 15(5): 646-653.

Citation:

SONG Zhang, CHENG Qiangong, ZHANG Wei, MENG Fanchao. 2007: ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS. JOURNAL OF ENGINEERING GEOLOGY, 15(5): 646-653.

SONG Zhang, CHENG Qiangong, ZHANG Wei, MENG Fanchao. 2007: ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS. JOURNAL OF ENGINEERING GEOLOGY, 15(5): 646-653.

Citation:

SONG Zhang, CHENG Qiangong, ZHANG Wei, MENG Fanchao. 2007: ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS. JOURNAL OF ENGINEERING GEOLOGY, 15(5): 646-653.

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ANALYSIS OF MICROSTRUCTURE FEATURE AND COLLAPSIBILITY OF UNDISTURBED LOESS

1.
College of Civil Engineering, Southwest Jiaotong University, Chengdu 610031;
2.
Institute of Geotechnical Investigation &|Design,MMI, Xi′an 710043;
3.
China Highway Planning and Design Institute, Beijing 100010

Funds:

Received Date: 2007-03-26
Rev Recd Date: 2007-04-27
Publish Date: 2007-09-29

Abstract

Abstract

Based on the scanning electron microscopy (SEM) of microstructure and collapsible test of undisturbed loess, the microstructure properties, the collapsible characteristics under different pressures and water contents, and the intrinsic mechanism between microstructure and collapsibility of loess were analyzed. The results indicated: (1) with the increasing of imbedding depth, the configuration of loess varying gradually from bracketed-macropore weak-cemented texture to inlaid-micropore half-cemented texture, the void properties from bracketed-macropore void to void among grains, then to micropore void; (2) the curves of coefficient of collapse-different pressures of loess under humidification can be divided into three phases, at the initial phase of compressive deformation was the course of loess compaction of structural strength, with a small settlement and microstructure no destroyed; (3) the second phase after the first turning point s=0.015 of the curves was the primary course of collapse deformation, the microstructure varying and particles redistributed with along the intrinsic texture of loess damaged , and ratio of collapsible settlement increased; and (4) the third, the new microstructure coming into being, the collapsible settlement decreased after the point of peak value. (5) the values of the initial collapsible pressure and the collapsible force of peak value increased, and the coefficient of collapse of peak value and the range values of pressures of collapsible settlement diminished as the increasing of imbedding depth; (6) the characteristics of framework grains and void of loess were the intrinsic influencing factors of collapsibility, and the amount and properties of cement were one of mainly contributing factors for the intensity of collapsibility of loess.
- Intact loess,
- Microstructure,
- Collapsibility,
- Coefficient of collapsibility,
- Intrinsic mechanism

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References(1)

References

[1] 刘祖典.黄土力学与工程
[M].西安:陕西科学技术出版社,1996.L iu Zud ian.Loess m echan ics and eng ineering.Xi'An:Shanxi Scien ce and T echnology Press,1996.

[2] 孙广忠.西北黄土的工程地质力学特性及地质工程问题研究
[M].兰州:兰州大学出版社,1989.Sun G uangzhong.S tudy on M echan ical Propert ies of Eng ineering G eology and G eological Eng ineering Prob lem s of Loess in N orh t w est Ch ina.Lanzhou:Lanzhou U n iversity P ress,1989.

[3] 孙建中.黄土学
[M].香港:香港考古学会出版,2005.Sun J ian zhong.Loess.H ongkong:H ongkong A rchaeology A ssoci at ion Press,2005.

[4] 冯连昌,郑宴武.中国湿陷性黄土
[M].北京:中国铁道出版社,1982.Feng L ianchang,Zheng Y awu.Col lap sed Loess in Ch ina.B eijing:Ch in a R aiwl ay Pub lish ing H ouse,1982.

[5] 谢定义.黄土力学特性与运用的过去、现在和未来
[J].地下空间,1999,19(6):274～284.X ie D ingy.i Past,today and fu tu re of so il m echan ical characteris tics and app licat ion of loess.U nderground Sp ace,1999,19(6):274～284.

[6] 雷胜友,唐文栋.黄土在受力和湿陷过程中微结构变化的CT扫描分析
[J].岩石力学与工程学报,2004,23(24):4166～4169.Lei Shengyou,T ang W endong.A nalys is of m icrostructu re ch ange for loess in the process of load ing and co llap se w ith CT scann ing.Ch inese Journal of R ock M echan ics and E ngineering,2004,23(24):4166～4169.

[7] 邵胜俊,周飞飞,龙吉勇.原状黄土结构性及定量化参数研究
[J].岩土工程学报,2004,26(4):531～537.Shao Shengjun,Zh ou Feife,i Long J iyong.S tructu re propert ies and its quant itat ive param eter.Ch inese Jou rnal of G eotechn ical Engineering,2004,26(4):531～537.

[8] 高国瑞.黄土湿陷变形的结构理论
[J].岩土工程学报,1990,12(4):1～10.G ao G uorui. A structu re theory for co llap sib le d eformat ion of loess soil. Ch inese Journal of G eotechn ical Eng ineering,1990,12(4):1 ～10.

[9] 骆亚生,谢定义,邵生俊等.非饱和黄土的结构变化特性
[J].西北农林科技大学学报(自然科学版),2004,32(8):114～118.Luo Y asheng,X ie D ingy,i Shao Sh engjun,Zhang A ijun.V ariation characteris tics of soil structu re of unsatu rated loess.Jour.of N orthw est Sci-Tech U n iv.of A gri. and For.(N a.tSc.i Ed.),2004,32(8):114～118.

[10] 关文章.湿陷性黄土工程性能新篇
[M].西安:西安交通大学出版社,1992.G uan W en zhang.N ew E ngineering Characteristics of C ollapsed Loess.X (iA n:X (ian J iaotong U n ivers ity Press,1997.

[11] 李兰.黄土微结构试验研究
[J].水文地质工程地质,2004,24(3):17～20.L i Lan.Study on m icrostru cture of loess.Hydrogeology and E ngineering G eology,2004,24(3):17～20.

[12] 顾成权,方云.黄土湿陷性的微观结构研究
[J].西部探矿工程,2003,(10):1～3.G u Chengqu an,Fang Y un.M icrostru cture of Loess Col laps ib ility.W est-Ch ina exp loration engin eer ing,2003,(10):1～3.

[13] 刘红枚,王兰民.饱和黄土液化的孔隙微结构特征
[J].西北地震学报,2002,24(2):135～139.L iu H ongm eng,W ang Lanm in.Study on the l iqu efact ion m echa n ism and pore m icrostructu re of saturated loess.N orthw est Seis molog ical Journal, 2002,24(2):135～139.

[14] 苗天德.湿陷性黄土的变形机理与本构关系
[J].岩土工程学报,1999,21(4):383～387.M iao T iande.D eform at ion m ech an ism and const itut ive relation of col lap sib le.Ch inese Journal of G eotechn ical Engin eering,1999,21(4):383～387.

[15] 陈正汉,刘祖典.黄土的湿陷变形机理
[J].岩土工程学报,1986,8(2):1～12.Ch en Zhenghan,L iu Zudian.M echan ism of col laps ib le deform a t ion of Loess.Ch inese Journal of G eotechn ical Engin eer ing,1986,8(2):1～12.

[16] 陈开圣.冲击压实技术在处治湿陷性黄土地基中的应用
[J].工程地质学报,2006,14(3):390～393.Ch en K aisheng.A pp licat ion of mi pact comp action technology in treating highw ay subgrade of collps ib le loess.Journal of E engineering G eolgoy,2006,14(3):390～393.

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