软土场地条件下路基桩地震反应特性  

Seismic Response Characteristics of Subgrade Pile Under Soft Soil Site Condition

作　　者：叶尔丰 许带军 YE Er-feng;XU Dai-jun(Jiangsu Jiaoke Traffic Design Institute Co.Ltd.,Huai’an 223000,China)

机构地区：[1]江苏交科交通设计研究院有限公司,江苏淮安223000

出　　处：《工程建设与设计》2021年第19期64-67,共4页Construction & Design for Engineering

摘　　要：在公路建设中,经常会面临土性较差的软土场地,其具有高孔隙性、高压缩性、低抗剪强度等特点,软土的存在常常会给路基设计带来难题,而桩基础是一种较好的地基加固方式,在公路设计中应用广泛。我国为地震多发区,发震频繁且烈度高,同时,公路作为震后救援重建的生命线,其重要性不言而喻,故而软土场地条件下路基桩动力响应问题具有很高的研究价值。论文以国内某高等级公路工程为背景,对场地-桩基础-路堤体系进行有限元建模,并挑选了频谱特性各不相同的2条地震记录作为基岩输入,进行非线性的动力反应分析。结果表明:边桩的动力反应明显大于内部桩,且动力反应均随深度变浅而增加,地表处最大。不同位置桩体的加速度反应的差异性在桩身中部更为明显,而相对位移的差异性则在地表处最为明显。In the construction of highway, it is often encountered the soft soil site with poor soil quality, which contains the characteristics of high porosity, high compressibility, low shear strength. The existence of soft soil often brings difficult problems to design of roadbed. Pile foundation is a good way to strengthen foundation and it is widely used in the design of highway. In China, earthquakes occur frequently and with high intensity, meanwhile, as the lifeline of rescue and reconstruction after the earthquake, the importance of the road is self-evident, therefore, the dynamic response of subgrade and pile under soft soil site condition has a high research value. In this paper, with a domestic highway project as the background, the finite element modeling of the system of site-pile foundation-embankment is carried out and two seismic records with different spectrum characteristics are selected as bedrock input for nonlinear dynamic analysis. Results show that: The dynamic response of the side pile is significantly larger than that of the internal pile, and the dynamic response increase with the depth decreases, and response at the surface is the strongest. The differences of acceleration response of the piles at different positions are more obvious in the middle of pile, while the differences of relative displacement are most obvious at the surface.

关 键 词：软土场地 公路工程 桩基础 土体非线性 地震反应 有限元分析法 

分 类 号：U416.12[交通运输工程—道路与铁道工程] U419.2