旋喷搅拌桩加固含易液化粉土夹层软基的现场试验

章定文; 刘涉川; 蔺文峰; 时洪斌; 毛忠良

doi:10.19818/j.cnki.1671-1637.2022.01.008

旋喷搅拌桩加固含易液化粉土夹层软基的现场试验

doi: 10.19818/j.cnki.1671-1637.2022.01.008

1.
东南大学交通学院, 江苏南京 211189
2.
中国水利水电第四工程局有限公司, 青海西宁 810007
3.
中铁第五勘察设计院集团有限公司, 北京 102600

基金项目:

国家自然科学基金项目 52078129

详细信息

作者简介:
章定文(1978-)，男，湖南常德人，东南大学教授，工学博士，从事岩土工程研究

中图分类号: U213.1
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出版历程
- 收稿日期: 2021-08-06
- 刊出日期: 2022-02-25

Field test on soft ground with liquefiable silt interlayer reinforced by jet-grouted mixing piles

1.
School of Transportation, Southeast University, Nanjing 211189, Jiangsu, China
2.
Sinohydro Engineering Bureau 4 Co., Ltd., Xining 810007, Qinghai, China
3.
China Railway Fifth Survey and Design Institute Group Co., Ltd., Beijing 102600, China

Funds:

National Natural Science Foundation of China 52078129

More Information

Author Bio:
ZHANG Ding-wen (1978-), male, professor, PhD, zhang@seu.edu.cn

Article Text (Baidu Translation)

摘要

摘要: 依托含易液化粉土夹层软基加固实体工程，采用现场试验的方法研究了旋喷搅拌桩加固含易液化粉土夹层软基的适用性和加固效果；通过钻孔取芯和静载试验测量分析了旋喷搅拌桩在含易液化粉土夹层软基中的成桩质量和桩芯强度；监测了路堤荷载下旋喷搅拌桩加固含易液化粉土夹层软基典型断面的施工期间及工后的地表沉降、深层水平位移、桩体荷载分担比、桩土应力比和超静孔隙水压力等数据，分析了旋喷搅拌桩加固含易液化粉土夹层软基的实际加固效果和工程受力特性。研究结果表明：旋喷搅拌桩在含易液化粉土夹层软基中可完整成桩，桩芯28 d无侧限抗压强度可达2.5 MPa，相对于常规搅拌桩强度提升了约一倍；在路堤荷载下，旋喷搅拌桩能有效地减小地基沉降和坡脚深层水平位移，并提高路堤的稳定性；旋喷搅拌桩加固地基桩土差异沉降较小，桩土应力比介于5~10，桩体荷载分担比小于50%，具有复合地基特性，复合地基分为柔性桩复合地基和刚性桩复合地基，两者设计方法差异很大，本文研究的旋喷搅拌桩建议按照柔性桩复合地基设计。可见，旋喷搅拌桩加固含易液化粉土夹层软基效果良好，可适用于实际工程。
- 岩土工程 /
- 地基处理 /
- 旋喷搅拌桩 /
- 现场试验 /
- 成桩质量 /
- 桩土应力比 /
- 复合地基
Abstract: For the engineering projects involving the reinforcement of soft ground with liquefiable silt interlayer, the applicability and effect of reinforcement using jet-grouted mixing piles were investigated on-site. The pile-forming quality and core strength of jet-grouted mixing pile were measured and analyzed by investigating the core samples obtained by drilling and static loading test. The data pertaining to ground surface settlement, deep horizontal displacement, pile load sharing ratio, pile-soil stress ratio, and excess pore water pressure were monitored under embankment load at a typical section of the soft ground during and after reinforcement. The reinforcement effect and stress characteristic on soft ground with liquefiable silt interlayer reinforced by the jet-grouted mixing piles were analyzed. Analysis results show that jet-grouted mixing piles can be successfully driven into the soft ground with liquefiable silt interlayer. The unconfined compressive strength of the pile core reaches 2.5 MPa at 28 d, which is nearly twice as high as the value of the core of conventional mixing pile. Under the embankment load, the jet-grouted mixing piles can effectively reduce the foundation settlement and the deep horizontal displacement at the toe of the slope, and improve the embankment stability. The pile-soil differential settlement is relatively small, the pile-soil stress ratio is 5-10, and the pile load sharing ratio is less than 50% in the jet-grouted mixing pile reinforced foundation, demonstrating the advantageous characteristic of the composite foundation. Composite foundation is divided into flexible pile composite foundation and rigid pile composite foundation. The design methods of the two are very different. The jet-grouted mixing piles studied in this paper is suggested to be designed as flexible pile composite foundation. Therefore, the soft ground with liquefiable silt interlayer reinforced by the jet-grouted mixing piles demonstrates satisfactory effect and can be used in practical engineering. 2 tabs, 12 figs, 30 refs.
- geotechnical engineering /
- ground improvement /
- jet-grouted mixing pile /
- field test /
- pile-forming quality /
- pile-soil stress ratio /
- composite foundation

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图 1 旋喷搅拌桩的施工设备

Figure 1. Construction equipment of jet-grouted mixing pile

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图 2 传感器埋设

Figure 2. Sensor embedding

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图 3 旋喷搅拌桩芯样

Figure 3. Core samples of jet-grouted mixing pile

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图 4 芯样无侧限抗压强度试验结果

Figure 4. Test results of unconfined compressive strengths of core samples

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图 5 旋喷搅拌桩单桩载荷试验结果

Figure 5. Load test results of single jet-grouted mixing pile

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图 6 路堤填高和地表沉降历时曲线

Figure 6. Curves of embankment height and ground surface settlement with time

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图 7 桩土差异沉降历时曲线

Figure 7. Curves of pile-soil different settlement with time

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图 8 路堤坡脚处深层水平位移

Figure 8. Deep horizontal displacements at toe of embankment slope

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图 9 不同位置处应力

Figure 9. Stresses at different positions

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图 10 不同位置桩土应力比

Figure 10. Pile-soil stress ratios at different positions

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图 11 不同位置桩体荷载分担比

Figure 11. Load share ratios of pile at different positions

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图 12 不同深度的超静孔隙水压力

Figure 12. Excess pore water pressures at different depths

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表 1 旋喷搅拌桩施工设备的技术参数

Table 1. Technical parameters of construction equipment of jet-grouted mixing pile

成桩深度/m	成桩直径/mm	钻杆动力/kW	卷扬机功率/kW	注浆泵排量/(L·min^-1)	喷射压力/MPa
0~25	500~800	55	75	125	10~25

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表 2 各土层物理力学性质指标

Table 2. Physical and mechanical properties of each soil layer

层号	土类	重度/(kN·m^-1)	土粒比重	含水率/%	孔隙比	液限/%	塑限/%	黏聚力/kPa	内摩擦角/(°)	压缩模量/MPa
1	粉土	19.6	2.70	25.8	0.780	28.0	19.8	9	27.6	10.11
2	软黏土	19.0	2.75	36.8	0.904	41.4	22.5	20	5.7	3.50
3	粉土	19.8	2.70	25.3	0.712	27.7	19.5	10	28.3	9.87
4	黏土	19.6	2.73	27.7	0.819	37.4	21.0	32	8.3	6.05
5	黏土	19.9	2.75	25.9	0.742	42.7	22.3	61	12.7	8.70

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参考文献(30)

[1]	YI Yao-lin, LIU Song-yu, PUPPALA A J, et al. Variable-diameter deep mixing column for multi-layered soft ground improvement: laboratory modeling and field application[J]. Soils and Foundations, 2019, 59(3): 633-643. doi: 10.1016/j.sandf.2019.01.009
[2]	张玉伟, 宋战平, 翁效林, 等. 黄土地铁隧道湿陷性基底地基处治优化模型试验[J]. 岩石力学与工程学报, 2020, 39(9): 1912-1920. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202009018.htm ZHANG Yu-wei, SONG Zhan-ping, WENG Xiao-lin, et al. Model test on treatment of collapsible loess foundation of metro tunnels[J]. Chinese Journal of Rock Mechanics and Engineering, 2020, 39(9): 1912-1920. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX202009018.htm
[3]	赵春风, 邹豫皖, 赵程, 等. 基于强度试验的五轴水泥土搅拌桩新技术研究[J]. 岩土工程学报, 2014, 36(2): 376-381. ZHAO Chun-feng, ZOU Yu-wan, ZHAO Cheng, et al. Experimental research on strength of five-axis cement-soil mixed piles[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(2): 376-381. (in Chinese)
[4]	SRIJAROEN C, HOY M, HORPIBULSUK S, et al. Soil-cement screw pile: alternative pile for low- and medium-rise buildings in soft Bangkok clay[J]. Journal of Construction Engineering and Management, 2021, 147(2): 04020173. doi: 10.1061/(ASCE)CO.1943-7862.0001988
[5]	NJOCK P G A, CHEN Jun, MODONI G, et al. A review of jet grouting practice and development[J]. Arabian Journal of Geosciences, 2018, 11(16): 1-31.
[6]	WANG Zhi-feng, SHEN Shui-long, MODONI G. Enhancing discharge of spoil to mitigate disturbance induced by horizontal jet grouting in clayey soil: theoretical model and application[J]. Computers and Geotechnics, 2019, 111: 222-228. doi: 10.1016/j.compgeo.2019.03.012
[7]	刘松玉, 周建, 章定文, 等. 地基处理技术进展[J]. 土木工程学报, 2020, 53(4): 93-110. https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC202004010.htm LIU Song-yu, ZHOU Jian, ZHANG Ding-wen, et al. State of the art of the ground improvement technology in China[J]. China Civil Engineering Journal, 2020, 53(4): 93-110. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC202004010.htm
[8]	CHAI Jin-chun, SHRESTHA S, HINO T, et al. 2D and 3D analyses of an embankment on clay improved by soil-cement columns[J]. Computers and Geotechnics, 2015, 68: 28-37. doi: 10.1016/j.compgeo.2015.03.014
[9]	JAMSAWANG P, YOOBANPOT N, THANASISATHIT N, et al. Three-dimensional numerical analysis of a DCM column-supported highway embankment[J]. Computers and Geotechnics, 2016, 72: 42-56. doi: 10.1016/j.compgeo.2015.11.006
[10]	SUN Yang, CHENG Jiu, LI Yi-wei, et al. Model test of the combined subgrade treatment by hydraulic sand fills and soil-cement mixing piles[J]. Bulletin of Engineering Geology and the Environment, 2020, 79(6): 2907-2918. doi: 10.1007/s10064-020-01735-9
[11]	PAVLOVI AC'G M N, COTSOVOS D M, DEDI AC'G M M, et al. Reinforced jet-grouted piles. Part 1: analysis and design[J]. Proceedings of the Institution of Civil Engineers-Structures and Buildings, 2010, 163(5): 299-308. doi: 10.1680/stbu.2010.163.5.299
[12]	YARMOHAMMADI F, RAFIEE-DEHKHARGHANI R, BEHNIA C, et al. Topology optimization of jet-grouted overlapping columns for mitigation of train-induced ground vibrations[J]. Construction and Building Materials, 2018, 190: 838-850. doi: 10.1016/j.conbuildmat.2018.09.156
[13]	SHEN Shui-long, ATANGANA NJOCK P G, ZHOU An-nan, et al. Dynamic prediction of jet grouted column diameter in soft soil using Bi-LSTM deep learning[J]. Acta Geotechnica, 2021, 16(1): 303-315. doi: 10.1007/s11440-020-01005-8
[14]	王小军, 楚华栋. 对粉/旋喷搅拌桩加固软弱地基的检测与评价[J]. 岩石力学与工程学报, 2003, 22(S2): 2908-2912. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2003S2076.htm WANG Xiao-jun, CHU Hua-dong. Test and evaluation on soft ground stabilized by chemical injection churning pile or chemical churning pile[J]. Chinese Journal of Rock Mechanics and Engineering, 2003, 22(S2): 2908-2912. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2003S2076.htm
[15]	高盟, 高广运, 冯世进, 等. 基坑开挖引起紧贴运营地铁车站的变形控制研究[J]. 岩土工程学报, 2008, 30(6): 818-823. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200806007.htm GAO Meng, GAO Guang-yun, FENG Shi-jin, et al. Control of deformation of operating subway station induced by adjacent deep excavation[J]. Chinese Journal of Geotechnical Engineering, 2008, 30(6): 818-823. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200806007.htm
[16]	FRANZ R J, CAMPER K E. Jet grout columns in mixed profile to control foundation settlement Gerald Ratner Athletics Center[C]//ASCE. Proceedings of the Third International Conference: Grouting and Ground Treatment. New York: ASCE, 2003: 389-400.
[17]	AXTELL P J, STARK T D. Increase in shear modulus by soil mix and jet grout methods[J]. DFI Journal, 2008, 2(1): 11-21. doi: 10.1179/dfi.2008.002
[18]	ROLLINS K M, HERBST M, ADSERO M, et al. Jet grouting and soil mixing for increased lateral pile group resistance[C]//ASCE. GeoFlorida 2010: Advances in Analysis, Modeling and Design. New York: ASCE, 2010: 1563-1572.
[19]	WONG R K N, WENG Y F, LEONG G K, et al. A case study of effectiveness of large diameter jet grout for soil improvement works in soft marine clay[J]. Lecture Notes in Civil Engineering, 2020, 62: 649-655.
[20]	JARITNGAM S. Design concept of the soil improvement for road construction on soft clay[C]//EASTS. Proceedings of the Eastern Asia Society for Transportation Studies. Tokyo: EASTS, 2003: 313-322.
[21]	毛忠良. 旋喷搅拌桩在软土地基处理工程中的应用[J]. 铁道建筑技术, 2016(11): 56-60. https://www.cnki.com.cn/Article/CJFDTOTAL-TDJS201611014.htm MAO Zhong-liang. Treatment for soft soil foundation used by jet-grouted mixing pile[J]. Railway Construction Technology, 2016(11): 56-60. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TDJS201611014.htm
[22]	吴厚信, 陈国勇, 周宏益, 等. 大直径深层旋喷搅拌桩在昊胜大厦深基坑支护工程中的应用[J]. 探矿工程(岩土钻掘工程), 2010, 37(4): 58-61. https://www.cnki.com.cn/Article/CJFDTOTAL-TKGC201004019.htm WU Hou-xin, CHEN Guo-yong, ZHOU Hong-yi, et al. Application of large-diameter deep mixing pile in the Haosheng Building foundation ditch engineering[J]. Exploration Engineering (Rock and Soil Drilling and Tunneling), 2010, 37(4): 58-61. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TKGC201004019.htm
[23]	陈云彬, 马德强. 临海厚砂质地层中防止基坑渗流破坏的工程实践[J]. 岩土工程学报, 2012, 34(S1): 461-464. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2012S1091.htm CHEN Yun-bin, MA De-qiang. Engineering practices of preventing seepage damage of excavations in coastal thick sand layer region[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(S1): 461-464. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2012S1091.htm
[24]	刘熙媛, 毛清志, 付士峰, 等. CFG桩基坑内施工对基坑周围环境稳定性的影响[J]. 地震工程学报, 2015, 37(3): 834-839. https://www.cnki.com.cn/Article/CJFDTOTAL-ZBDZ201503031.htm LIU Xi-yuan, MAO Qing-zhi, FU Shi-feng, et al. Influence of CFG piles construction in foundation pit on surrounding environmental stability[J]. China Earthquake Engineering Journal, 2015, 37(3): 834-839. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZBDZ201503031.htm
[25]	GUAN Cheng-li, YANG Yu-you. Field study on the water stop of the Rdin jet pile method in a water-rich sandy gravel stratum[J]. Applied Sciences, 2019, 9(8): 1709. doi: 10.3390/app9081709
[26]	王延宁, 蒋斌松, 于健, 等. 港珠澳大桥岛隧结合段高压旋喷桩地基沉降试验及研究[J]. 岩石力学与工程学报, 2017, 36(6): 1514-1521. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201706023.htm WANG Yan-ning, JIANG Bin-song, YU Jian, et al. In-situ experiment on composite foundation of high pressure jet grouting piles of Hong Kong-Zhuhai-Macau Bridge[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(6): 1514-1521. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201706023.htm
[27]	武崇福, 李玉, 张志军. 桩锚支护体系竖向土拱效应分析与桩后土压力计算[J]. 交通运输工程学报, 2014, 14(3): 24-33. https://www.cnki.com.cn/Article/CJFDTOTAL-JYGC201403006.htm WU Chong-fu, LI Yu, ZHANG Zhi-jun. Vertical soil arch effect analysis and soil pressure calculation behind piles for pile-anchor supporting system[J]. Journal of Traffic and Transportation Engineering, 2014, 14(3): 24-33. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-JYGC201403006.htm
[28]	杨涛, 王刚刚, 闫业强, 等. 桩承式路堤中土拱形态与成拱过程中土拱效应研究[J]. 岩土工程学报, 2014, 36(4): 731-735. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201404023.htm YANG Tao, WANG Gang-gang, YAN Ye-qiang, et al. Shape of soil arching and development of its effect in a piled embankment[J]. Chinese Journal of Geotechnical Engineering, 2014, 36(4): 731-735. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201404023.htm
[29]	HAN Jie, YE Shu-lin. Simplified method for consolidation rate of stone column reinforced foundations[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2001, 127(7): 597-603. doi: 10.1061/(ASCE)1090-0241(2001)127:7(597)
[30]	章定文, 谢伟, 郑晓国. 考虑桩土非等应变的路堤荷载下搅拌桩复合地基沉降计算方法[J]. 岩土力学, 2014, 35(S2): 68-74. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX2014S2010.htm ZHANG Ding-wen, XIE Wei, ZHENG Xiao-guo. Composite ground settlement calculating method with displacement non-compatibility between deep mixing columns and surrounding soil[J]. Rock and Soil Mechanics, 2014, 35(S2): 68-74. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX2014S2010.htm