Centrifugal model test on the performance of pile-supported reinforced-earth structure for subgrade widening
LI Li1，CAO Wenzhao2，LIU Yang1，ZHENG Junjie1，LI Bo3
(1. Institute of Geotechnical and Underground Engineering，Huazhong University of Science and Technology，Wuhan，Hubei 430074，China；2. Central Research Institute of Building and Construction(Shenzhen) Co.，Ltd.，MCC Group，Shenzhen，Guangdong 518055，China；3. Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources，
Yangtze River Scientific Research Institute，Wuhan，Hubei 430010，China)
Abstract：As a new kind of widening structure with smaller occupied area，lower cost of ground treatment and less requirement for fill，the pile-supported reinforced-earth wall(PSRW) has been used to widen the four-lane expressway. By means of centrifugal model test，both the PSRW and the geosynthetic-reinforced pile-supported embankment(GRPS) are used respectively to widen the existing subgrades that with or without piles. A total of 4 cases are selected and both the external deformation and internal stress characteristics after widening are obtained. The test results demonstrate that the PSRW has better stability than the GRPS when used for subgrade widening，because the GRPS widen subgrade built on the original subsoil without consolidation directly without slope cutting. Widening by PSRW can reduce the surface settlement of the subgrade effectively. When the existing subgrade with piles is widened by GRPS，the effect of widened subgrade on the piles at the central axis of subgrade is far greater than that of widened by PSRW，while the axial force of piles is slightly less.
李 立1，曹文昭2，刘 洋1，郑俊杰1，李 波3. 桩承式加筋土结构拓宽路基工作特性离心模型试验[J]. 岩石力学与工程学报, 2021, 40(S2): 3357-3366.
LI Li1，CAO Wenzhao2，LIU Yang1，ZHENG Junjie1，LI Bo3. Centrifugal model test on the performance of pile-supported reinforced-earth structure for subgrade widening. , 2021, 40(S2): 3357-3366.
[1] 刘观仕，孔令伟，李雄威，等. 高速公路软土路基拓宽粉喷桩处治方案分析与验证[J]. 岩石力学与工程学报，2008，27(2)：309–315.(LIU Guanshi，KONG Lingwei，LI Xiongwei，et al. Analysis of treatment scheme for soft foundation in expressway widening project and its verification[J]. Chinese Journal of Rock Mechanics and Engineering，2008，27(2)：309–315.(in Chinese))
[2] 贾 宁，陈仁朋，陈云敏，等. 杭甬高速公路拓宽工程理论分析及监测[J]. 岩土工程学报，2004，26(6)：755–760.(JIA Ning，CHEN Renpeng，CHEN Yunmin，et al. Theoretical analysis and measurement for widening project of Hang-Yong expressway[J]. Chinese Journal of Geotechnical Engineering，2004，26(6)：755–760.(in Chinese))
[3] 陈 亮，唐承耀，刘军勇. 道路拓宽改建常见病害与路基拼接技术研究[J]. 土工基础，2015，29(3)：62–65.(CHEN Liang，TANG Chengyao，LIU Junyong. Common highway embankment hazards and construction techniques of transition zone between existing and new embankmen[J]. Soil Engineering and Foundation，2015，29(3)：62–65.(in Chinese))
[4] WEI Y G，ZHOU W F，LI Y Y. Management research on treatment measures for differential settlement of Tianjin—Binhai expressway?s widened subgrade[J]. Applied Mechanics and Materials，2014，505–506：28–34.
[5] 吕伟华，缪林昌，王 非，等. 桩–网加固拓宽路堤土拱效应试验研究[J]. 岩土力学，2013，34(8)：2 316–2 322.(LÜ Weihua，MIAO Linchang，WANG Fei，et al. Experimental study of soil arching of geogrid-reinforced and pile-supported widening embankment[J]. Rock and Soil Mechanics，2013，34(8)：2 316–2 322.(in Chinese))
[6] 刘观仕，孔令伟，丁 锋，等. 高速公路扩建工程软基拓宽的沉降监测与分析[J]. 岩土力学，2007，28(2)：331–335.(LIU Guanshi，KONG Lingwei，DING Feng，et al. Settlement monitoring and analysis for soft foundation of an expressway widening project[J]. Rock and Soil Mechanics，2007，28(2)：331–335.(in Chinese))
[7] HUANG X M，WANG H. Comparison between responses of reinforced and unreinforced embankments due to road widening[J]. Journal of Central South University of Technology，2009，16(5)：857–864.
[8] JIN S W，CHOO Y W，KIM Y M，etal. Centrifuge modeling of differential settlement and levee stability due to staged construction of enlarged embankment[J]. KSCE Journal of Civil Engineering，2014，18(4)：1 036–1 046.
[9] WENG X L，ZHANG L J，WANG W. Research on the treatment for water damage to widened subgrade of collapsible loess based on centrifuge[J]. Applied Mechanics and Materials，2011，99–100：821–825.
[10] 陈 磊，刘汉龙，陈永辉. 高速公路拓宽工程地基处理效果的数值分析[J]. 岩土力学，2006，27(11)：2 066–2 070.(CHEN Lei，LIU Hanlong，CHEN Yonghui. Numerical analysis of foundation improvement effect for expressway widening engineering[J]. Rock and Soil Mechanics，2006，27(11)：2 066–2 070.(in Chinese))
[11] 史启超，曹卫平. 深厚软基高速公路拓宽新老路堤相互作用分析[J]. 地下空间与工程学报，2011，7(增2)：1 792–1 797.(SHI Qichao，CAO Weiping. Analysis of interaction between existing and widened embankments of highway over soft soil[J]. Chinese Journal of Underground Space and Engineering，2011，7(Supp.2)：1 792– 1 797.(in Chinese))
[12] YU H，WANG Y M，ZOU C，et al. Study on subgrade settlement characteristics after widening project of highway built on weak foundation[J]. Arabian Journal for Science and Engineering，2017，42(9)：3 723–3 732.
[13] JIANG X，JIANG Y，WU C Y，et al. Numerical analysis for widening embankments over soft soils treated by PVD and DJM columns[J]. International Journal of Pavement Engineering，2020，21(3)：267–279.
[14] 王家全，周 健，丛 林，等. 高填方加筋新旧路堤现场试验与数值模拟分析[J]. 岩石力学与工程学报，2010，29(增1)：2 943–2 950. (WANG Jiaquan，ZHOU Jian，CONG Lin，et al. Analysis between numerical and field tests of high fill reinforced widening embankment[J]. Chinese Journal of Rock Mechanics and Engineering，2010，29(Supp.1)：2 943–2 950.(in Chinese))
[15] ZHAO M X，LIU C Y，EL-KORCHI T，et al. Performance of geogrid-reinforced and PTC pile-supported embankment in a highway widening project over soft soils[J]. Journal of Geotechnical and Geoenvironmental Engineering，2019，145(11)：06 019 014.
[16] 钱劲松，凌建明. 路基拓宽工程中桩承式加筋路堤处理的数值分析[J]. 交通运输工程学报，2008，8(5)：67–71.(QIAN Jinsong，LING Jianming. Numerical analysis of application for pile-supported reinforced embankment in subgrade widening engineering[J]. Journal of Traffic and Transportation Engineering，2008，8(5)：67–71.(in Chinese))
[17] AHMAD S M，CHOUDHURY D. Pseudo-dynamic approach of seismic design for waterfront reinforced soil wall[J]. Geotextiles and Geomembranes，2008，26(4)：291–301.
[18] LI L H，YANG J C，XIAO H L，et al. Behavior of tire-geogrid-reinforced retaining wall system under dynamic vehicle load[J]. International Journal of Geomechanics，2020，20(4)：04020017.
[19] VISWANADHAM B V S，KOENI D. Centrifuge modeling of geotextile-reinforced slopes subjected to differential settlements[J]. Geotextiles and Geomembranes，2009，27(2)：77–88.
[20] 姜彦彬，何 宁，何 斌，等. 复合地基离心模型试验桩土应力分布测试分析[J]. 岩土工程学报，2020，42(增1)：85–89.(JIANG Yanbin，HE Ning，HE Bin，et al. Distribution of pile-soil stress in centrifugal modelling of composite foundation[J]. Chinese Journal of Geotechnical Engineering，2020，42(Supp.1)：85–89.(in Chinese))
[21] XU P，JIANG G. Investigation of the influence of foundation deformability on reinforced soil retaining walls using centrifuge model tests[J]. Soil Mechanics and Foundation Engineering，2020，57(5)：155–161.
[22] XU P，HATAMI K，JIANG G. Centrifuge study of reinforced soil walls with different backfill compaction densities[J]. Geosynthetics International，2020，27(5)：538–550.
[23] HUANG Y，XU X，LIU J，et al. Centrifuge modeling of seismic response and failure mode of a slope reinforced by a pile-anchor structure[J]. Soil Dynamicss and Earthquake Engineering，2020，131：106037.
[24] SABOYA F，TIBANA S，REIS R M，et al. Centrifuge modeling of soft soil reinforced with granular columns[J]. Geotechnical and Geological Engineering，2021，39(1)：2 955–2 967.
2021, Vol. 40 
