黄土场地桩基横向力学行为数值模拟
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摘要
为探讨黄土地区桩基的水平承载特性,研究桩基在桩顶水平荷载作用下的内力和变形分布规律。借助有限元软件ANSYS建立桩基半结构模型,结合水平加载制度,深入探究桩基的横向承载能力,对桩长、桩径进行了参数分析。结果表明:桩顶水平荷载作用下,桩-土界面有明显的相互作用力学行为,桩-土界面分离深度可达4.5 d,桩径比桩长参数对桩基的抗侧移刚度和水平承载力影响更显著,桩基减震耗能能力有限。
In order to investigate the horizontal bearing characteristics of the pile foundation in a loess area, the distribution law for the internal force and deformation of a pile foundation under horizontal loading at the top of a pile was studied. The finite element software ANSYS was used to establish a semi-structural mode for the pile foundation. Combined with a horizontal loading system, the lateral bearing capacity of the pile foundation was deeply explored, and the parameters of pile length and pile diameter were analyzed. The results show that the pile-soil interface has an obvious interaction mechanics behavior under horizontal loading at pile top. The depth of pile-soil interface separation can reach 4.5 d. The influence of pile diameter on the lateral stiffness and horizontal bearing capacity of a pile foundation is more significant than that of pile length, and the seismic energy dissipation capacity of a pile foundation is limited.
In order to investigate the horizontal bearing characteristics of the pile foundation in a loess area, the distribution law for the internal force and deformation of a pile foundation under horizontal loading at the top of a pile was studied. The finite element software ANSYS was used to establish a semi-structural mode for the pile foundation. Combined with a horizontal loading system, the lateral bearing capacity of the pile foundation was deeply explored, and the parameters of pile length and pile diameter were analyzed. The results show that the pile-soil interface has an obvious interaction mechanics behavior under horizontal loading at pile top. The depth of pile-soil interface separation can reach 4.5 d. The influence of pile diameter on the lateral stiffness and horizontal bearing capacity of a pile foundation is more significant than that of pile length, and the seismic energy dissipation capacity of a pile foundation is limited.
引文
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[4]胡伟,王宏,肖天崟.桩体长径比对桩基动力特性的影响研究[J].岩土力学,2010,31(9):2845―2848.Hu Wei,Wang Hong,Xiao Tianyin.Research on influence of pile's slenderness ratio on pile-soil-structure system’s dynamic interaction[J].Rock and Soil Mechanics,2010,31(9):2845―2848.(in Chinese)
[5]冯君,张俊云,朱明,等.软土地层高承台桥梁群桩基础横向承载特性研究[J].岩土力学,2016,37(增刊2):94―104.Feng Jun,Zhang Junyun,Zhu Ming,et al.Characteristic study of horizontal bearing capacity and pile group effect coefficient of laterally loaded high pile group foundation for bridge in soft soil[J].Rock and Soil Mechanics,2016,37(Suppl 2):94―104.(in Chinese)
[6]李晋.黄土地区桩基桩土共同作用性状仿真与试验研究[J].岩石力学与工程学报,2008,27(5):1081.Li Jin.Simulation of pile-soil interaction behavior of bridge pile in loess area and its test study[J].Chinese Journal of Rock Mechanics and Engineering,2008,27(5):1081.(in Chinese)
[7]吴奕喆,吴亚平,舒春生,等.浸水及固结过程对湿陷性黄土桩基力学特性影响的机理分析[J].科学技术与工程,2018,18(2):146―152.Wu Yizhe,Wu Yaping,Shu Chunsheng,et al.Mechanism analysis of influence of immersion and consolidation process on mechanical proper-ties of collapsible loess pile foundation[J].Science Technology and Engineering,2018,18(2):146―152.(in Chinese)
[8]赵明华,尹平保,杨明辉,等.考虑土体液化侧移影响的轴横向受荷桩内力与位移分析[J].铁道学报,2014,36(4):86―92.Zhao Minghua,Yin Pingbao,Yang Minghui,et al.Analysis on inner-force and displacement of piles under axial and lateral loads considering lateral displacement of surrounding liquefied soils mass[J].Journal of the China Railway Society,2014,36(4):86―92.(in Chinese)
[9]王建华,冯士伦.液化土层中桩基水平承载特性分析[J].岩土力学,2005,26(10):76-80.Wang Jianhua,Feng Shilun.Research on lateral resistance of pile foundation in liquefaction strata[J].Rock and Soil Mechanics,2005,26(10):76―80.(in Chinese)
[10]冯士伦,王建华,郭金童.液化土层中桩基抗震性能振动台试验研究[J].土木工程学报,2005(7):92―95.Feng Shilun,Wang Jianhua,Guo Jintong.A shake table test on the seismic resistance of pile foundation in liquefied soil[J].China Civil Engineering Journal,2005(7):92―95.(in Chinese)