预制混凝土微型桩广泛应用于南水北调工程含长大裂隙膨胀土边坡抢险加固工程,研究其加固力学机制,对膨胀土边坡安全防护具有重要意义。在相似模型试验的基础上,建立含裂隙面边坡滑体及微型单排桩模型;以平行裂隙面方向施加推阻力,开展了相似模型试验及数值模拟。结果表明:微型单排桩加固表现出较好的阻滑效果,将坡体系统的抗滑力维持在较高水平,边坡抵抗破坏的韧性增加,边坡稳定性显著提高。边坡抗滑阻力随桩间距增加而减小,单根微型桩的影响范围有限,随着桩间距的增大,土拱效应逐渐减弱,当桩间距为12倍桩直径时,桩之间的相互作用可以忽略,建议桩间距取8倍桩直径;布置在边坡中部的微型桩加固效果较布置在边坡上1/3位置的微型桩加固效果更好。
Abstract
The widely application of precast concrete micro piles in the emergency reinforcement of expansive soil slope with long cracks in the South-to-North Water Diversion Project highlights their significance in ensuring slope safety. Studying the reinforcement mechanism is essential. Based on similar model test, a model was established to examine the interaction between the sliding mass and the micro single row pile in the slope with fracture surface. A thrust force was applied parallel to the fracture surface, and both similar model test and numerical simulation were conducted. The results demonstrated the effectiveness of preventing sliding by micro single row pile reinforcement. It maintained a high level of anti-sliding force in the slope system, increased slope toughness against failure, and significantly improved slope stability. The slope’s resistance to sliding decreased as the pile spacing increased. The influence of a single micro pile only extended over a limited range. As the pile spacing increased, the soil arching effect gradually weakened. Ignoring the interaction between piles became feasible when the pile spacing exceeded 12 times the pile diameter. It is recommended to maintain a pile spacing 8 times of the pile diameter. Moreover, the strengthening effect of micro piles arranged in the middle of the slope surpassed that of those arranged in the upper 1/3 of the slope.
关键词
微型桩 /
缓倾长大裂隙 /
膨胀土边坡 /
相似模型试验 /
数值模拟
Key words
micro pile /
gently inclined long fissure /
expansive soil slope /
similarity model test /
numerical simulation
{{custom_sec.title}}
{{custom_sec.title}}
{{custom_sec.content}}
参考文献
[1] 王小波, 蔡耀军, 李 亮, 等. 南水北调中线膨胀土开挖边坡破坏特点与机制[J]. 人民长江, 2015, 46(1): 26-29.(WANG Xiao-bo, CAI Yao-jun, LI Liang, et al. Failure Characteristics and Mechanism of Excavated Expansive Soil Slope of MRP of South-To-North Water Diversion[J]. Yangtze River, 2015, 46(1): 26-29.(in Chinese))
[2] 陆定杰, 陈善雄, 罗红明, 等. 南阳膨胀土渠道滑坡破坏特征与演化机制研究[J]. 岩土力学, 2014, 35(1): 189-196.(LU Ding-jie, CHEN Shan-xiong, LUO Hong-ming, et al. Study of Failure Characteristics and Evolution Mechanism of Canal Slope of Nanyang Expansive Soil[J]. Rock and Soil Mechanics, 2014, 35(1): 189-196.(in Chinese))
[3] 庞毅玲. 广西百色地区某膨胀土边坡破坏成因机制与防治措施研究[J]. 广西城镇建设, 2019(9): 121-123.(PANG Yi-ling. Study on the Failure Mechanism and Prevention Measures of an Expansive Soil Slope in Baise, Guangxi[J]. Cities and Towns Construction in Guangxi, 2019(9): 121-123.(in Chinese))
[4] 殷宗泽, 韦 杰, 袁俊平, 等. 膨胀土边坡的失稳机理及其加固[J]. 水利学报, 2010, 41(1): 1-6.(YIN Zong-ze, WEI Jie, YUAN Jun-ping, et al. Mechanism of Slope Slide of Expansive Soil and Reinforcement for the Slope[J]. Journal of Hydraulic Engineering, 2010, 41(1): 1-6.(in Chinese))
[5] 张 锐. 合肥地区膨胀土裂隙发育和下渗特性试验研究[D]. 合肥: 安徽建筑大学, 2014.(ZHANG Rui. Experimental Study on Crack Expansion and Infiltration Characteristics of Expansive Soils in Hefei Area[D]. Hefei: Anhui Jianzhu University, 2014.(in Chinese))
[6] 陈 强, 韩 军, 刘自楷, 等. 武汉绕城高速公路生态防护膨胀土边坡失稳的几种形式及加固处理[J]. 岩石力学与工程学报, 2006, 25(增刊2): 4040-4045.(CHEN Qiang, HAN Jun, LIU Zi-kai, et al. Several Forms of Instability of Expansive Soil Slope for Ecological Protection of Wuhan Ring Expressway and Its Reinforcement Treatment[J]. Chinese Journal of Rock Mechanics and Engineering, 2006, 25(Supp.2): 4040-4045.(in Chinese))
[7] 郑 勇. 膨胀土边坡失稳成因机制及其演化过程分析[J]. 中国水运(下半月),2009,9(12):152-153.(ZHENG Yong.Cause Mechanism and Evolution Process Analysis of Expansive Soil Slope Instability[J]. China Water Transport,2009,9(12):152-153.(in Chinese))
[8] 邓铭江, 蔡正银, 朱 洵, 等. 北疆渠道膨胀土边坡破坏机制及加固措施[J]. 岩土工程学报, 2020, 42(增刊2): 50-55.(DENG Ming-jiang, CAI Zheng-yin, ZHU Xun, et al. Failure Mechanism and Reinforcement Measures of Expansive Soil Slope in Northern Xinjiang Channel[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(Supp.2): 50-55.(in Chinese))
[9] LIANG C, WU Z, LIU X, et al. Analysis of Shallow Landslide Mechanism of Expansive Soil Slope under Rainfall: A Case Study[J]. Arabian Journal of Geosciences, 2021, 14(7): 584.
[10] XIAO J, TONG C, YANG H P. Causes of Shallow Landslides of Expansive Soil Slopes[J]. Journal of Highway and Transportation Research and Development, 2017, 11: 1-6.
[11] HUANG Z, WEI B, ZHANG L, et al. Surface Crack Development Rules and Shear Strength of Compacted Expansive Soil Due to Dry–Wet Cycles[J]. Geotechnical and Geological Engineering, 2019, 37(4): 2647-2657.
[12] 张晓斌. 缓倾滑坡成因机制及其防治技术研究[D]. 福州: 福州大学, 2016.(ZHANG Xiao-bin. Formation Mechanism of Gently Inclined Landslide and Prevention and Control Technologies[D].Fuzhou:Fuzhou University, 2016.(in Chinese))
[13] 刘雅君, 罗文柯. 膨胀土边坡失稳特征与多维防治技术研究[J]. 四川建材, 2010, 36(4): 87-91.(LIU Ya-jun, LUO Wen-ke. Research on Instable Character of Expansive Soil Slope and Multidimensional Control Technology[J]. Sichuan Building Materials, 2010, 36(4): 87-91.(in Chinese))
[14] 逯卓奇, 陈虹旭, 王靓露, 等. 微型桩加固边坡计算理论及试验研究综述[J]. 公路, 2017, 62(5): 16-20.(LU Zhuo-qi, CHEN Hong-xu, WANG Liang-lu, et al. Reviews of Theoretical and Experimental Researches on Applications of Micro-pile in Slope Reinforcement[J]. Highway, 2017, 62(5): 16-20.(in Chinese))
[15] ELSAIED A E. Performance of Footing with Single Side Micro-piles Adjacent to Slopes[J]. Alexandria Engineering Journal, 2014, 53(4): 903-910.
[16] 谷拴成, 甄希翠. 微型桩加固边坡的合理桩间距确定[J]. 地下空间与工程学报, 2015, 11(6): 1617-1621.(GU Shuan-cheng, ZHEN Xi-cui. Analysis of Micropile’s Slope Reinforcement and Determination of Rational Pile Spacing[J]. Chinese Journal of Underground Space and Engineering, 2015, 11(6): 1617-1621.(in Chinese))
[17] 刘 续. 注浆微型桩加固边坡计算方法探讨[J]. 工程建设与设计, 2015(1): 69-71, 74.(LIU Xu. Discussion on the Calculation Method of Grouting Micropiles Used for Reinforced Slope[J]. Construction & Design for Engineering, 2015(1): 69-71, 74.(in Chinese))
[18] KHAN M S, HOSSAIN S, AHMED A, et al. Investigation of a Shallow Slope Failure on Expansive Clay in Texas[J]. Engineering Geology, 2017, 219: 118-129.
[19] ABDOLLAHI K, MORTEZAEI A. A New Expression for Determining the Bending Stiffness of Circular Micropile Groups[J]. Soil Dynamics and Earthquake Engineering, 2015, 77: 58-70.
[20] LAHUTA H, ALDORF J, HRUBESOVA E, et al. Influence of Buckling at the Rod Micropiles[J]. Procedia Engineering, 2016, 142: 328-333.
[21] 邓友生, 刘华飞, 姚志刚, 等. 微型桩群的抗滑机理及设计理论的研究[J]. 公路, 2014, 59(12): 20-26.(DENG You-sheng, LIU Hua-fei, YAO Zhi-gang, et al. Landslide Control Mechanism and Study of Design Theory for Micro-pile Groups[J]. Highway, 2014, 59(12): 20-26.(in Chinese))
[22] 辛建平, 郑颖人, 唐晓松. 基于弹塑性模型的微型抗滑桩破坏机制研究[J]. 岩石力学与工程学报, 2014, 33(增刊2): 4113-4121.(XIN Jian-ping, ZHENG Ying-ren, TANG Xiao-song. Study on Failure Mechanism of Micro Anti-slide Pile Based on Elastic-plastic Model[J]. Chinese Journal of Rock Mechanics and Engineering, 2014, 33(Supp.2): 4113-4121.(in Chinese))
[23] IAI S. Similitude for Shaking Table Tests on Soil-structure-fluid Model in 1g Gravitational Field[J]. Soils and Foundations, 1989, 29(1): 105-118.
基金
国家自然科学基金面上项目(42272315)
PDF(7005 KB)
