Please wait a minute...
浙江大学学报(工学版)
浙江大学学报(工学版)  2021, Vol. 55 Issue (6): 1027-1035    DOI: 10.3785/j.issn.1008-973X.2021.06.002
交通工程、土木工程     
循环荷载下长短桩桩网复合地基变形试验研究
杨以国1,2(),刘开富3,*(),谢新宇1,4
1. 浙江大学 滨海和城市岩土工程研究中心，浙江 杭州 310058
2. 浙江大学 宁波理工学院，浙江 宁波 315100
3. 浙江理工大学 建筑工程学院，浙江 杭州 310018
4. 浙江大学 温州研究院，浙江 温州 325035
Experimental research on deformation of pile-net composite foundation with long-short piles under cyclic load
Yi-guo YANG1,2(),Kai-fu LIU3,*(),Xin-yu XIE1,4
1. Research Center of Coastal and Urban Geotechnical Engineering, Zhejiang University, Hangzhou 310058, China
2. Ningbo Institute of Technology, Zhejiang University, Ningbo 315100, China
3. School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou 310018, China
4. Institute of Wenzhou, Zhejiang University, Wenzhou 325035, China
 全文: PDF(1415 KB)   HTML
摘要：

通过长短桩桩网复合地基的模型试验，分析有、无土工格栅及不同幅值循环荷载下复合地基沉降、长短桩桩身应变及土工格栅应变的特性. 试验结果表明，土工格栅的加入会改善循环荷载下复合地基的整体性能. 复合地基沉降、桩身应变及土工格栅应变主要发生在循环荷载作用前期. 增大循环荷载幅值不仅会增大复合地基总沉降，还会加快沉降发展的速率. 复合地基的沉降与循环次数的关系可以用指数函数表示. 土工格栅的拉膜效应将部分荷载由桩间土传递到桩上，相比于没有土工格栅的复合地基，有土工格栅的复合地基中长短桩的应变更大，且此时长桩桩帽处的土工格栅会承受更大的拉力，应变相较于桩间土处更大；循环荷载下的长桩上部应变增量较大，下部应变增量较小.
关键词： 长短桩;  桩网复合地基;  循环荷载;  地基沉降;  桩身应变;  土工格栅应变    
Abstract:

The model test was conducted on geosynthetic-reinforced pile-supported composite foundation with long-short piles. The characteristics of settlement, pile strain and geogrid strain of the composite foundation were analyzed under cyclic load with different amplitudes with or without geogrid. Results show that the addition of geogrid can improve the overall performance of composite foundation under cyclic load. The foundation settlement, pile strain and geogrid strain mainly occur in the early stage of cyclic load. Increasing the amplitude of cyclic load not only increases the final settlement, but also increases the increasing rate of the settlement. The relationship between composite foundation settlement and number of load cycles can be expressed by exponential function. The membrane effect generated by the geogrid causes the stress of the soil among piles to transmit to the pile top. The strain of long-short piles in composite foundation with geogrid is larger than that without geogrid. Geogrid near the pile top takes more tension and has larger strain than that near the soil among piles. The strain increment of long pile is larger in the upper part of the pile under cyclic load, which is smaller in the lower part.
Key words: long-short piles    geosynthetic-reinforced pile-supported composite foundation    cyclic load    foundation settlement    pile strain    geogrid strain
收稿日期: 2020-07-10 出版日期: 2021-07-30
CLC:  U 416  
基金资助: 国家自然科学基金资助项目（51878619）；浙江省自然科学基金资助项目（LY13E090010）
通讯作者: 刘开富     E-mail: 21812130@zju.edu.cn;liukaifu@zstu.edu.cn
作者简介: 杨以国（1996—），男，硕士生，从事桩网复合地基的研究.orcid.org/0000-0001-8320-9536. E-mail： 21812130@zju.edu.cn
服务　　
把本文推荐给朋友
加入引用管理器
E-mail Alert
作者相关文章　　
杨以国
刘开富
谢新宇

引用本文:

杨以国,刘开富,谢新宇. 循环荷载下长短桩桩网复合地基变形试验研究[J]. 浙江大学学报(工学版), 2021, 55(6): 1027-1035.

Yi-guo YANG,Kai-fu LIU,Xin-yu XIE. Experimental research on deformation of pile-net composite foundation with long-short piles under cyclic load. Journal of ZheJiang University (Engineering Science), 2021, 55(6): 1027-1035.

链接本文:

https://www.zjujournals.com/eng/CN/10.3785/j.issn.1008-973X.2021.06.002    或    https://www.zjujournals.com/eng/CN/Y2021/V55/I6/1027

图 1  岩土工程灾变模拟系统
图 2  桩应变测点布置
土 ρ /（g·cm?3） ww /% c /kPa φ /（°） ωL /% ωP /%
粉质黏土 1.69 17.1 8.1 26.5 ? ?
淤泥质黏土 1.62 42.1 ? ? 40 27
表 1  黏土的物理性质参数
土工格栅规格 网格尺寸 断裂强度/（kN·m?1）
TGSG15-15 30 mm $ \times $30 mm ≥42.1
表 2  土工格栅的物理性质参数
图 3  长短桩桩网复合地基模型试验布置图
图 4  不同幅值的循环荷载加载曲线
图 5  静载加载曲线
试验编号 土工格栅 Fc1 /kN Fc2 /kN Fc3 /kN
1 有 8±3 9±4 10±5
2 无 8±3 ? ?
表 3  加载方案
图 6  （8±3）kN循环荷载下有、无土工格栅桩网的复合地基循环次数-沉降曲线
图 7  不同幅值循环荷载下桩网复合地基循环次数-沉降曲线
图 8  复合地基循环荷载幅值-沉降对比曲线
循环荷载幅值/kN α β C R2
8±3 1.038 ?0.0366 ?1.158 0.9882
9±4 1.220 ?0.0379 ?1.399 0.9876
10±5 1.535 ?0.0334 ?1.788 0.9847
表 4  参数α、β的拟合值、常数项C及确定系数R2
图 9  （8±3）kN循环荷载下无土工格栅刚性长桩的桩身应变-桩深曲线
图 10  （8±3）kN循环荷载下有土工格栅刚性长桩的桩身应变-桩深曲线
图 11  （8±3）kN循环荷载下有、无土工格栅柔性短桩的桩身应变-桩深对比曲线
图 12  不同幅值的循环荷载下有土工格栅刚性长桩的桩身应变-桩深曲线
图 13  不同幅值的循环荷载下有土工格栅柔性短桩的桩身应变-桩深曲线
图 14  （8±3）kN循环荷载下的土工格栅应变分布曲线
图 15  不同幅值的循环荷载下土工格栅应变-循环次数曲线
1 郑刚, 龚晓南, 谢永利, 等 地基处理技术发展综述[J]. 土木工程学报, 2012, 45 (2): 127- 146
ZHENG Gang, GONG Xiao-nan, XIE Yong-li, et al State-of-the-art techniques for ground improvement in China[J]. China Civil Engineering Journal, 2012, 45 (2): 127- 146
2 刘海涛, 谢新宇, 程功, 等 刚-柔性桩复合地基试验研究[J]. 岩土力学, 2005, 26 (2): 303- 306
LIU Hai-tao, XIE Xin-yu, CHENG Gong, et al Experimental study of the rigid-flexible pile composite foundation[J]. Rock and Soil Mechanics, 2005, 26 (2): 303- 306
doi: 10.3969/j.issn.1000-7598.2005.02.028
3 李波, 黄茂松, 程岳, 等 路堤荷载下长短桩组合型复合地基现场试验与数值模拟[J]. 中国公路学报, 2013, 26 (1): 9- 14
LI Bo, HUANG Mao-song, CHENG Yue, et al Field test and numerical analysis of composite foundation with long and short piles under embankment[J]. China Journal of Highway and Transport, 2013, 26 (1): 9- 14
doi: 10.3969/j.issn.1001-7372.2013.01.002
4 杨鹏, 李照东, 胡永涛, 等 刚柔性桩复合地基加固双层软弱地基现场试验研究[J]. 土木建筑与环境工程, 2018, 40 (6): 1- 8
YANG Peng, LI Zhao-dong, HU Yong-tao, et al Field test of double-layered soft ground improved by rigid-flexible composite pile foundation[J]. Journal of Civil, Architectural and Environmental Engineering, 2018, 40 (6): 1- 8
5 YE G B, WANG M, ZHANG Z, et al Geosynthetic-reinforced pile-supported embankments with caps in a triangular pattern over soft clay[J]. Geotextiles and Geomembranes, 2020, 48 (1): 52- 61
doi: 10.1016/j.geotexmem.2019.103504
6 郎瑞卿, 闫澍旺, 赵栋 多层加筋垫层刚性桩网复合地基的承载特性[J]. 土木与环境工程学报(中英文), 2019, 41 (3): 49- 57
LANG Rui-qing, YAN Shu-wang, ZHAO Dong Analysis of bearing capacity of rigid pile-net composite foundation with multi-layer reinforced cushion[J]. Journal of Civil and Environmental Engineering, 2019, 41 (3): 49- 57
7 芮瑞, 夏元友 桩-网复合地基与桩承式路堤的对比数值模拟[J]. 岩土工程学报, 2007, 29 (5): 769- 772
RUI Rui, XIA Yuan-you Numerical simulation and comparison of pile-net composite foundation with pile-supported embankment[J]. Chinese Journal of Geotechnical Engineering, 2007, 29 (5): 769- 772
doi: 10.3321/j.issn:1000-4548.2007.05.023
8 曹卫平, 陈仁朋, 陈云敏 桩承式加筋路堤土拱效应试验研究[J]. 岩土工程学报, 2007, 29 (3): 436- 441
CAO Wei-ping, CHEN Ren-peng, CHEN Yun-min Experimental investigation on soil arching in piled reinforced embankments[J]. Chinese Journal of Geotechnical Engineering, 2007, 29 (3): 436- 441
doi: 10.3321/j.issn:1000-4548.2007.03.021
9 费康, 陈毅, 王军军 加筋形式对桩承式路堤工作性状影响的试验研究[J]. 岩土工程学报, 2012, 34 (12): 2312- 2317
FEI Kang, CHEN Yi, WANG Jun-jun Experimental study on influence of reinforcing modes on behavior of piled embankment[J]. Chinese Journal of Geotechnical Engineering, 2012, 34 (12): 2312- 2317
10 WANG H L, CHEN R P, LIU Q W, et al Investigation on geogrid reinforcement and pile efficacy in geosynthetic-reinforced pile-supported track-bed[J]. Geotextiles and Geomembranes, 2019, 47 (6): 755- 766
doi: 10.1016/j.geotexmem.2019.103489
11 XING H F, ZHANG Z, LIU H B, et al Large-scale tests of pile-supported earth platform with and without geogrid[J]. Geotextiles and Geomembranes, 2014, 42 (1): 586- 598
12 曹新文, 卿三惠, 周立新 桩网复合地基土工格栅加筋效应的试验研究[J]. 岩石力学与工程学报, 2006, 25 (1): 3162- 3167
CAO Xin-wen, QING San-hui, ZHOU Li-xin Experimental study on reinforcement effect of geogrid on composite foundation with dry jet mixing piles[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25 (1): 3162- 3167
13 白顺果, 侯永峰, 张鸿儒 循环荷载下柔性桩复合地基永久沉降影响因素的试验研究[J]. 岩土工程学报, 2010, 32 (8): 1309- 1313
BAI Shun-guo, HOU Yong-feng, ZHANG Hong-ru Experimental study on influence factors for permanent settlement of composite ground with flexible piles under cyclic loadings[J]. Chinese Journal of Geotechnical Engineering, 2010, 32 (8): 1309- 1313
14 高昂, 张孟喜, 朱华超, 等 循环荷载及静载下土工格室加筋路堤模型试验研究[J]. 岩土力学, 2016, 37 (7): 1921- 1928
GAO Ang, ZHANG Meng-xi, ZHU Hua-chao, et al Model tests on geocell-reinforced embankment under cyclic and static loadings[J]. Rock and Soil Mechanics, 2016, 37 (7): 1921- 1928
15 牛婷婷, 刘汉龙, 丁选明, 等 高铁列车荷载作用下桩网复合地基振动特性模型试验[J]. 岩土力学, 2018, 39 (3): 872- 880
NIU Ting-ting, LIU Han-long, DING Xuan-ming, et al Piled embankment model test on vibration characteristics under high-speed train loads[J]. Rock and Soil Mechanics, 2018, 39 (3): 872- 880
16 ALAM M J I, GNANENDRAN C T, LO S R Experimental and numerical investigations of the behaviour of footing on geosynthetic reinforced fill slope under cyclic loading[J]. Geotextiles and Geomembranes, 2018, 46 (6): 848- 859
doi: 10.1016/j.geotexmem.2018.08.001
17 WANG J Q, ZHANG L L, XUE J F, et al Load-settlement response of shallow square footings on geogrid-reinforced sand under cyclic loading[J]. Geotextiles and Geomembranes, 2018, 46 (5): 586- 596
doi: 10.1016/j.geotexmem.2018.04.009
18 MOGHADDAS T S N, DAWSON A R Behaviour of footings on reinforced sand subjected to repeated loading: comparing use of 3D and planar geotextile[J]. Geotextiles and Geomembranes, 2010, 28 (5): 434- 447
doi: 10.1016/j.geotexmem.2009.12.007
19 MOGHADDAS T S N, DAWSON A R A comparison of static and cyclic loading responses of foundations on geocell-reinforced sand[J]. Geotextiles and Geomembranes, 2012, 32: 55- 68
doi: 10.1016/j.geotexmem.2011.12.003
20 蔡袁强, 赵莉, 曹志刚, 等 不同频率循环荷载下公路路基粗粒填料长期动力特性试验研究[J]. 岩石力学与工程学报, 2017, 36 (5): 1238- 1246
CAI Yuan-qiang, ZHAO Li, CAO Zhi-gang, et al Experimental study on dynamic characteristics of unbound granular materials under cyclic loading with different frequencies[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36 (5): 1238- 1246
21 浙江省住房和城乡建设厅. 复合地基技术规范: GBT 50783-2012 [S]. 北京: 中国计划出版社, 2012: 71-74.
22 中交路桥技术有限公司. 公路沥青路面设计规范: JTG D50—2017 [S]. 北京: 人民交通出版社股份有限公司, 2017: 44-45.
23 杨龙才, 郭庆海, 周顺华, 等 高速铁路桥桩在轴向循环荷载长期作用下的承载和变形特性试验研究[J]. 岩石力学与工程学报, 2005, 24 (13): 2362- 2368
YANG Long-cai, GUO Qing-hai, ZHOU Shun-hua, et al Dynamic behaviors of pile foundation of high-speed railway bridge under long-term cyclic loading in soft soil[J]. Chinese Journal of Rock Mechanics and Engineering, 2005, 24 (13): 2362- 2368
doi: 10.3321/j.issn:1000-6915.2005.13.027
24 LI L H, CUI F L, FERREIRA P, et al Experimental study of embankments with different reinforcement materials and spacing between layers[J]. Geotextiles and Geomembranes, 2019, 47 (4): 477- 482
doi: 10.1016/j.geotexmem.2019.03.003
25 高昂, 张孟喜, 刘芳, 等 分级循环荷载下土工格室加筋路堤模型试验研究[J]. 岩土力学, 2016, 37 (8): 2213- 2221
GAO Ang, ZHANG Meng-xi, LIU Fang, et al Model experimental study of embankment reinforced with geocells under stepped cyclic loading[J]. Rock and Soil Mechanics, 2016, 37 (8): 2213- 2221
[1] 李亚峰,聂如松,冷伍明,程龙虎,梅慧浩,董俊利. 间歇性循环荷载作用下细粒土的变形特性[J]. 浙江大学学报(工学版), 2020, 54(11): 2109-2119.
[2] 刘俊伟, 朱娜, 王立忠, 尚文昌. 循环荷载下砂与钢板界面的弱化机制[J]. 浙江大学学报(工学版), 2018, 52(6): 1123-1130.
[3] 庄妍, 程欣婷, 肖衡林, 刘奂孜, 周倍合, 李嘉俊. 桩承式路堤中加筋褥垫层的工作性状[J]. 浙江大学学报(工学版), 2018, 52(12): 2279-2284.
[4] 王彤, 谢旭, 唐站站, 沈赤. 考虑复杂应变历史的钢材修正双曲面滞回模型[J]. 浙江大学学报(工学版), 2015, 49(7): 1305-1312.
[5] 胡安峰, 张光建, 贾玉帅, 张晓冬. 刚度衰减模型在大直径桩累积侧向位移分析中的应用[J]. J4, 2014, 48(4): 721-726.
[6] 王忠瑾,谢新宇,方鹏飞,李金柱,金伟良. 刚性长短组合桩的非线性沉降计算分析[J]. J4, 2014, 48(3): 463-470.
[7] 胡亚元. 考虑次固结时循环荷载引起的软基沉降[J]. J4, 2011, 45(1): 106-111.
[8] 蔡袁强 陈静 王军. 循环荷载下各向异性软黏土应变-软化模型[J]. J4, 2008, 42(6): 1058-1064.
[9] 王军 陈张林 蔡袁强 刘飞禹. 考虑软化特性的软黏土动应力-应变关系研究[J]. J4, 2007, 41(1): 26-28.