新疆板块状盐渍土工程特性

FENG Zhong-ju; LI Wei-zhou; WANG Ting-wu; LIU Xiao-fei; CHENG Chao

doi:10.19818/j.cnki.1671-1637.2010.06.001

新疆板块状盐渍土工程特性

doi: 10.19818/j.cnki.1671-1637.2010.06.001

冯忠居^1,,
李维洲^{1, 2},
王廷武³,
刘小飞⁴,
成超¹

1.
长安大学公路学院, 陕西西安 710064
2.
中交第二航务工程局有限公司, 湖北武汉 430040
3.
新疆维吾尔自治区交通厅, 新疆乌鲁木齐 830000
4.
广东省公路勘察规划设计院有限公司, 广东广州 510507
5.
中交第一公路勘察设计研究院有限公司, 陕西西安 710075

基金项目:

Scientific Research of National West Communications Construction 2009 318 000 03

Communications Technology Project of Xinjiang Uygur Autonomous Region 200609251

详细信息

中图分类号: U416.16
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出版历程
- 收稿日期: 2010-07-21
- 刊出日期: 2010-12-25

Engineering characteristics of plate-like saline soil in Xinjiang

1.
School of Highway, Chang'an University, Xi'an 710064, Shaanxi, China
2.
CCCC Second Harbour EngineeringCompany Ltd., Wuhan 430040, Hubei, China
3.
Communications Department of Xinjiang Uygur Autonomous Region, Urumqi 830000, Xinjiang, China
4.
Guangdong Highway Design Institute Co., Ltd., Guangzhou 510507, Guangdong, China
5.
CCCC First Highway Consultants Co., Ltd., Xi'an 710075, Shaanxi, China

Funds:

Scientific Research of National West Communications Construction 2009 318 000 03

Communications Technology Project of Xinjiang Uygur Autonomous Region 200609251

More Information

Author Bio:
FENG Zhong-ju(1965-), Male, Wanrong, Shanxi, Professor of Chang' an University, PhD, Research on Geotechnical Engineering, +86-29-82334881, ysf@gl.chd.edu.cn

摘要

摘要: 采用室内颗粒分析试验、界限含水量(质量分数) 试验、击实试验、强度特性试验、变形特性试验和溶胀试验分析了板块状盐渍土工程特性。分析结果表明: 板块状盐渍土主要由砾类土构成, 其级配因取土样位置而差异较大; 塑性指数范围、最大干密度范围与最佳含水量范围分别为0.57~3.20、2.22~2.25 g.cm^-3与5.7%~6.2%;天然状态下的无侧限抗压强度最大值为28.6 MPa, 具有岩石的特性, 属于盐岩; 板块状盐渍土为低压缩性土, 满足高速公路地基变形指标要求; 在水、热环境的变化下, 随着板块状盐渍土含盐量的增大, 溶陷系数与盐胀力(量) 增大, 盐胀起胀温度随着硫酸钠含量的增加有较大幅度的提前; 盐渍土地区公路交通荷载可抑制其盐胀, 从而可以降低盐胀对工程产生的病害。
- 路基工程 /
- 板块状盐渍土 /
- 工程特性 /
- 击实特性 /
- 强度特性 /
- 变形特性 /
- 溶胀特性 /
- 盐胀特性 /
- 无侧限抗压强度
Abstract: The engineering characteristics of plate-like saline soil were analysed on the basis of laboratory particle size analysis test, water content (mass percentage) limit test, compaction test, strength test, deformation test and swelling test.Analysis result shows that plate-like saline soil is mainly made up of gravelly soil and has different gradations resulted from sampling locations.The ranges of plasticity index, maximum dry density and optimum moisture content are 0.57~3.20, 2.22~2.25 g·cm-3 and 5.7%~6.2% respectively.Under natural condition, its maximum unconfined compressive strength is 28.6 MPa, and it has the characteristics of rocks and belongs to rock salt.Plate-like saline soil has low compressibility and meets the deformation index requirement of highway subgrade.Under the change of water and heat environment, with the increase of salinity, the coefficient of collapsibility and salt-expansion stress increase, and the salt-expansion temperature reaches ahead of time as the sodium sulfate content increases.Salt expansion can be controlled by vehicle load, which reduces the engineering disease resulted from salt expansion.
- subgrade engineering /
- plate-like saline soil /
- engineering characteristics /
- compaction characteristic /
- strength characteristic /
- deformation characteristic /
- swelling characteristic /
- salt-expansion characteristic /
- unconfined compressive strength

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Figure 1. Curves of particle distributions

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Figure 2. Compaction curves

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Figure 3. Test device for salt expansion

1-Soil sample; 2-Dial indicator; 3-Protective layer; 4-Cryogenic

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Figure 4. Salt-expansion forces

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Figure 5. Salt-expansion amounts

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Table 1. Test program

Sample	Type of salt	Experiment content	Remark
2^#	Salt of excess chloride	Particle size Water content limit Compaction characteristic Strength characteristic Deformation characteristic Swelling characteristic	Plate-like
4^#
5^#
6^#
7^#	Salt of moderate sulfate		Nonplate-like
8^#	Salt of less sulfate		Nonplate-like
9^#	Salt of excess chloride		Plate-like
12^#
13^#

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Table 2. Computation results of C_uand C_c

Sample	C_u	C_c	Evaluation result
2^#	24.40	1.30	Well-graded gravel
4^#	25.79	0.18	Poorly-graded gravel
5^#	29.30	1.60	Well-graded gravel
6^#	24.12	0.70	Poorly-graded gravel
7^#	36.15	0.41	Poorly-graded gravel

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Table 3. Liquid limits and plastic limits

Sample	Liquid limit	Plastic limit	Plasticity index
4^#	14.62	14.05	0.57
6^#	17.50	14.40	3.10
7^#	16.43	14.60	1.83
12^#	18.10	14.90	3.20

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Table 4. Results of compaction test

Sample	Maximum dry density/ (g·cm^-3)	Optimum moisture content/%
2^#	2.22	6.0
4^#	2.24	5.7
6^#	2.25	6.2
7^#	2.25	6.0
12^#	2.25	5.9
13^#	2.22	5.8

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Table 5. Compressive strengths

Sample	Compressive strength/MPa						Average value /MPa
4^#	2.8	3.0	3.5	4.0	4.4	5.2	3.80
5^#	11.7	20.0	20.2	20.4	21.2	27.6	20.20
6^#	4.2	5.1	5.3	6.3	9.6	28.6	9.85

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Table 6. Comparison of Uniaxial compressive strengths

Sample	Compressive strength/MPa	Remark
4^#	2.8~ 5.2	Result of test
5^#	11.7~27.6
6^#	4.2~28.6
Marlite	3.5~18.0	Reference^[7]
Sandstone	4.5~10.0
Ribbon shale	6.0~8.0

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Table 7. Result of compressive test

Sample	Compressive modulus/MPa	Coefficient of compressibility/MPa^-1
5^#	30.16	0.05
6^#	25.87	0.06
7^#	21.67	0.07
8^#	6.09	0.31
9^#	3.20	0.59

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Table 8. Evaluation standard of compressive deformation

Compressibility	Compressive modulus/MPa	Coefficient of compressibility/MPa^-1
High	< 4	> 0.5
Mid	4~15	0.5~0.1
Low	> 15	< 0.1

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Table 9. Coefficients of collapsibility

Sample	Coefficient of collapsibility
4^#	0.472
5^#	0.455
6^#	0.236
12^#	0.475

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Table 10. Salt-expansion characteristics of samples

Sample	Temperature of beginning expansion/℃		Dramatic salt-expansion range/℃		Maximum salt-expansion force/kPa
Sample	Loading	Unloading	Loading	Unloading	Maximum salt-expansion force/kPa
2^#	-10	20	-15→-20	-5→-20	7.29
4^#	10	20	-5→-20	0→-20	14.58
7^# (a)	5	15	-10→-20	5→-15	7.81
7^# (b)	10		5→-15		13.54
7^# (c)	20		20→0		16.14

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参考文献(21)

[1]	BAO Wei-xing, LI Zhi-nong. Testing on transmutation properties of saline soil under freezing and thawing cycles in Kashi, Xinjiang[J]. Journal of Chang'an University: Natural Science Edition, 2008, 28(2): 26-30. (in Chinese)
[2]	PING Shu-jiang, LI Wei-guang, SHEN Ai-qin, et al. Re- inforcement mechanism of fine chlorine saline soil on middle and lower alluvial plains of Yellow River[J]. Journal of Chang'an University: Natural Science Edition, 2008, 28(4): 21-26. (in Chinese)
[3]	WANG Jun-chen. Study on the salty and frost swelling of ulfate(sulfurous)salty soil fills in Shuimohe Plain, North of Tianshan[D]. Changchun: Jilin University, 2005. (in Chinese)
[4]	YANG Bao-cun, LIU Xin-rong, HE Xing-hong, et al. Test study on saline soil subgrade salt-frost deformation[J]. Chinese Journal of Underground Space and Engineering, 2009, 5(3): 594-603. (in Chinese)
[5]	LI Fang, LI Bin, CHEN Jian. Highway-related dividing scheme of salty soil[J]. Journal of Chang'an University: Natural Science Edition, 2006, 26(6): 12-14, 89. (in Chinese)
[6]	WANG Chun-lei, XIE Qiang, JIANG Chong-xi, et al. Analysis of thermal characteristics and mechanical properties of salty soil in frozen area of Qinghai-Tibet Railway[J]. Rock and Soil Mechanics, 2009, 30(3): 836-839. (in Chinese)
[7]	Highway and Transportation Society of Xinjiang. Technial guidelines for highway design and construction in the saline soil regions[R]. Beijing: China Communications Press, 2006. (in Chinese)
[8]	LI Zhi-nong, JIN Chang-ning. Test on dry compaction of typical earth subgrade in Xinjiang[J]. China Journal of Highway and Transport, 2007, 20(2): 23-28. (in Chinese)
[9]	ZHANG Sha-sha, YANG Xiao-hua, XIE Yong-li, et al. Salt-expansion laws of coarse-grained salty soil in road subgrade[J]. Journal of Chang' an University: Natural Science Edition, 2009, 29(1): 20-25. (in Chinese)
[10]	FENG Zhong-ju. Foundation Engineering in Special Areas[M]. Beijing: China Communications Press, 2008. (in Chinese)
[11]	BAO Wei-xing, YANG Xiao-hua, XIE Yong-li. Research on salt expansion of representative crude saline soil under freezing and thawing cycles [J]. Chinese Journal of Geotechnical Engineering, 2006, 28(11): 1991-1995. (in Chinese)
[12]	ZHANG Zhi-feng, HAO Fei, SHEN Jian-jun, et al. Test on mechanic properties of graded soil[J]. Journal of Chang'an University: Natural Science Edition, 2009, 29(4): 16-19. (in Chinese)
[13]	AI-HADDABI M, AHMED M. Land disposal of treated saline oil production water: impacts on soil properties[J]. Desalination, 2007, 212(1/2/3): 54-61.
[14]	KARIUKI P C, VAN DER MEER F. A unified swelling potential index for expansive soils[J]. Engineering Geology, 2004, 72(1/2): 1-8.
[15]	FENG De-cheng, YI Jun-yan, WANG Dong-sheng, et al. Impact of salt and freeze-thaw cycles on performance of asphalt mixtures in coastal frozen region of China[J]. Cold Regions Science and Technology, 2010, 62(1): 34-41. doi: 10.1016/j.coldregions.2010.02.002
[16]	FENG Zhong-ju, ZHANG Yong-qing. Compaction test of coarse-grained soil subgrade[J]. Journal of Chang'an University: Natural Science Edition, 2004, 24(3): 9-12. (in Chinese)
[17]	FENG Zhong-ju, XIE Yong-li. Numerical method to result analysis of indoor standard compaction test[J]. Journal of Chang'an University: Natural Science Edition, 2002, 22(2): 10-13. (in Chinese)
[18]	GUO Zhi-yong. Experiment and dynamic properties of improved expansive soil[J]. Journal of Chang'an University: Natural Science Edition, 2003, 23(4): 18-21. (in Chinese)
[19]	CHENG Hai-tao, LIU Bao-jian, XIE Yong-li. Deformation characteristics of remolded loess[J]. Journal of Chang'an University: Natural Science Edition, 2008, 28(5): 31-34. (in Chinese)
[20]	LI Shi-fang. Salt and frost heaving composite diseases of frozen saline soil area[J]. Road Machinery and Construction Mechanization, 2009, 26(2): 60-63(in Chinese)
[21]	FENG Zhong-ju, WU Yan-ling, CHENG Chao, et al. Salt-dissolution and salt-heaving characteristics of plate-like saline soil[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(9): 1439-1442. (in Chinese)