Journal of Jilin University(Engineering and Technology Edition) ›› 2020, Vol. 50 ›› Issue (2): 613-620.doi: 10.13229/j.cnki.jdxbgxb20181147

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Dynamic resilient modulus for unsaturated clay soils considering effect of limited moisture content fluctuation

Jian-ming LING1(),Hui CHEN1,Jin-song QIAN1(),Ding ZHOU2   

  1. 1.Key Laboratory of Road and Traffic Engineering of the Ministry of Education, Tongji University, Shanghai 201804, China
    2.Shanghai Urban Construction Design & Research Institute, Shanghai 200125, China
  • Received:2018-11-19 Online:2020-03-01 Published:2020-03-08
  • Contact: Jin-song QIAN E-mail:jmling@tongji.edu.cn;qianjs@tongji.edu.cn

Abstract:

The resilient modulus (MR) is an important parameter to characterize the elastic support performance of subgrade. MR is significantly affected by subgrade limited moisture content fluctuation after traffic opening. Soil-water characteristic curve (SWCC) tests were conducted to investigate the relationship between MR and degree of saturation of the compacted and unsaturated clay soils. Repeated load triaxial (RLT) tests were carried out to obtain MR under three moisture conditions: different moisture contents, drying or wetting path and different moisture fluctuations, to investigate the correlation between MR and matric suction. The prediction model of MR under moisture fluctuation was proposed based on the matric suction. Test results show that the MR has a good non-linear relationship with matric suction. The MR of the drying path is greater than that of wetting path under the same moisture content. With the number of moisture fluctuations increases, the dynamic MR can be firstly decreased by 23%~37% when the moisture fluctuation is 1~2 times, then MR gradually stabilizes. The influence of the frequency and amplitude of moisture fluctuation on the dynamic MR can be considered simultaneously in the proposed prediction model, and the model has higher predicting accuracy compared with the models depend on degree of saturation.

Key words: road and railway engineering, clay soil, resilient modulus, matric suction, limited moisture fluctuation, reduction factor

CLC Number: 

  • TU411

Fig.1

SWCC tests"

Table 1

Test results of SWCC"

基质吸力/kPa饱和度/%
4872.13
10356.90
14248.99
20343.94
25840.45
30437.84
35835.80

Fig.2

Fitting results of test data of SWCC"

Fig.3

Upside seepage wetting method"

Fig.4

Oven dehydration method"

Fig.5

Diagram of moisture contents in drying or wetting path"

Fig.6

Diagram of moisture contents under limited humidity fluctuation"

Fig.7

Curves of resilient modulus vs. matric suction"

Fig.8

Resilient modulus under wetting and drying pathes"

Fig.9

Relationship between number of humidity fluctuations and resilience modulus when amplitude is ±2%"

Fig.10

Relationship between number of humidity fluctuations and resilience modulus when amplitude is ±4%"

Table 2

Regression analysis results for prediction models"

模型k1k2k3k4R2
文献[26]1.687-0.823-1.251-0.0120.76
本文2.284-0.059-0.027-0.95

Table 3

Regression analysis results for prediction models"

模型k1k2k3k4R2
文献[26]2.152-0.832-3.805-0.0030.86
本文27.451-0.053-0.840-0.95

Fig.11

Measured η versus predicted η values"

1 Seed H B, Chan C K, Lee C E. Resilience characteristics of subgrade soils and their relation to fatigue failures in asphalt pavements[C]∥International Conference on the Structural Design of Asphalt Pavements. Supplement. Ann Arbor: University of Michigan, 1962.
2 凌建明, 陈声凯, 曹长伟. 路基土回弹模量影响因素分析[J]. 建筑材料学报, 2007, 10(4): 446-451.
Ling Jian-ming, Chen Sheng-kai, Cao Chang-wei. Analysis of influence factors on resilient modulus of subgrade soils[J]. Journal of Building Materials, 2007, 10(4): 446-451.
3 Li D, Selig E T. Resilient modulus for fine-grained subgrade soils[J]. Journal of Geotechnical Engineering, 1994, 120(6): 939-957.
4 Drumm E C, Reeves J S, Madgett M R, et al. Subgrade resilient modulus correction for saturation effects[J]. Journal of Geotechnical and Geoenvironmental Engineering, 1997, 123(7): 663-670.
5 杨树荣. 路基土壤之不饱和吸力特性及反复载重下之力学行为[D]. 台湾: 台湾中央大学土木工程系, 2005.
Yang Shu-rong. Behavior of unsaturated subgrade soils under repeated loading[D]. Taiwan: Department of Civil Engineering, National Central University of Taiwan, 2005.
6 张世洲, 凌建明, 罗志刚, 等. 路基土动态模量试验研究[J]. 北方交通, 2008(6): 18-21.
Zhang Shi-zhou. Ling Jian-ming, Luo Zhi-gang,et al. Research on experiment of dynamic modulus of subgrade soil[J]. Beifang Jiaotong, 2008(6): 18-21.
7 邱欣, 钱劲松, 张世洲. 基于基质吸力的粘性路基土动回弹模量预估模型研究[J]. 水文地质工程地质, 2011, 38(3): 49-53.
Qiu Xin, Qian Jin-song, Zhang Shi-zhou. Research on prediction model of dynamic resilient modulus of subgrade soil based on matric suction[J]. Hydrogeology & Engineering Geology, 2011, 38(3): 49-53.
8 钱劲松, 李嘉洋, 周定, 等. 考虑吸力效应的非饱和黏土回弹模量预估模型[J]. 岩土力学, 2018, 39(1): 123-128.
Qian Jin-song, Li Jia-yang, Zhou Ding, et al. Prediction model of resilient modulus for unsaturated clay soils considering the effect of matric suction[J]. Rock & Soil Mechanics, 2018, 39(1): 123-128.
9 李聪. 基于非饱和土理论的路基回弹模量研究[D]. 重庆: 重庆交通大学交通运输学院, 2007.
Li Cong. The study on resilient modulus taking into account theoretic of unsaturated soils[D]. Chongqing: College of Traffic and Transportation, Chongqing Jiaotong University, 2007.
10 杨和平, 张锐, 郑健龙. 有荷条件下膨胀土的干湿循环胀缩变形及强度变化规律[J]. 岩土工程学报, 2006, 28(11): 1936-1941.
Yang He-ping, Zhang Rui, Zheng Jian-long. Variation of deformation and strength of expansive soil during cyclic wetting and drying under loading condition[J]. Chinese Journal of Geotechnical Engineering, 2006, 28(11): 1936-1941.
11 冉武平, 李玲, 陶泽峰. 基于正交试验的路基回弹模量影响因素分析[J]. 公路工程, 2015, 40(5): 40-44, 55.
Ran Wu-ping, Li Ling, Tao Ze-feng. Analysis of influence factors of subgrade modulus of resilience based on the orthogonal experiment[J]. Highway Engineering, 2015, 40(5): 40-44, 55.
12 Jin M S, Lee K W, Kovacs W D. Seasonal variation of resilient modulus of subgrade soils[J]. Journal of Transportation Engineering, 1994, 120(4): 603-616.
13 Phan T H, Cushman M D, White D J, et al. Seasonal variation in the subgrade and base layers of US Highway20, Iowa[C]∥Mid-Continent Transportation Research Symposium. Iowa: Iowa Department of Transportation, 2007.
14 AASHTO. Guide for the development of bicycle facilities[M]. Washington, DC: Officials, H T, 1999.
15 中华人民共和国交通部. JTG E40—2007, 公路土工试验规程[M]. 北京: 交通部公路科学研究院, 2007.
16 Fredlund D G, Xing A. Equations for the soil-water characteristic curve[J]. Canadian Geotechnical Journal, 1994, 31(4): 521-532.
17 Brooks R H, Corey A T. Hydraulic Properties of Porous Media[M]. Fort Collins, Colorado: Colorado State University, 1964.
18 Abu-Farsakh M Y, Mehrotra A, Mohammad L, et al. Incorporating the effect of moisture variation on resilient modulus for unsaturated fine-grained subgrade soils[C]∥Proceedings of the 94th Annual Meeting of the Transportation Research Board. Washington D C: Transportation Research Board, 2015.
19 Cary C E, Zapata C E. Resilient modulus for unsaturated unbound materials[J]. Road Materials & Pavement Design, 2011, 12(3): 615-638.
20 AASHTO. T307—99, Standard Method of Test for Resilient Modulus of Subgrade Soils and Untreated Base/Subbase Materials[M]. Washington D C: American Association of State Highway and Transportation Officials, 1999.
21 Gupta S C, Ranaivoson A, Edil T B, et al. Pavement Design Using Unsaturated Soil Technology[R]. St. Paul, Minnesota: Minnesota Department of Transportation, 2007.
22 Fredlund D G. The 1999 R.M. hardy lecture: the implementation of unsaturated soil mechanics into geotechnical engineering[J]. Canadian Geotechnical Journal, 2000, 37(5): 963-986.
23 Ng C W W, Xu J, Yung S Y. Effects of wetting–drying and stress ratio on anisotropic stiffness of an unsaturated soil at very small strains[J]. Canadian Geotechnical Journal, 2009, 46(9): 1062-1076.
24 汪东林, 栾茂田, 杨庆. 非饱和重塑黏土干湿循环特性试验研究[J]. 岩石力学与工程学报, 2007, 26(9): 1862-1867.
Wang Dong-lin, Luan Mao-tian, Yang Qing. Experimental study on behaviour of unsaturated remoulded clay subjected to drying and wetting cyclic paths[J]. Chinese Journal of Rock Mechanics & Engineering, 2007, 26(9): 1862-1867.
25 张芳枝, 陈晓平. 反复干湿循环对非饱和土的力学特性影响研究[J]. 岩土工程学报, 2010, 32(1): 41-46.
Zhang Fang-zhi, Chen Xiao-ping. Influence of repeated drying and wetting cycles on mechanical behaviors of unsaturated soil[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(1): 41-46.
26 李冬雪, 凌建明, 钱劲松, 等. 湿度循环下黏质路基土回弹模量演化规律[J]. 同济大学学报: 自然科学版, 2013, 41(7): 1051-1055.
Li Dong-xue, Ling Jian-ming, Qian Jin-song, et al. Influence of moisture content change cyclicity on modulus evolution law of cohesive subgrade Soil[J]. Journal of Tongji University (Natural Science), 2013, 41(7): 1051-1055.
27 李聪, 邓卫东, 崔相奎. 干湿循环条件下完全扰动黄土路基回弹模量分析[J]. 交通科学与工程, 2009, 25(2): 8-12.
Li Cong, Deng Wei-dong, Cui Xiang-kui. The study on resilient modulus of remolded loess in moisture circulation process[J]. Journal of Transport Science & Engineering, 2009, 25(2): 8-12.
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