| 列车激振荷载下PCC桩复合地基动力分析 |
| |
| 引用本文： | 付强,丁选明,刘汉龙,孔纲强.列车激振荷载下PCC桩复合地基动力分析[J].岩土力学,2013,34(Z2):413-420. |
| |
| 作者姓名： | 付强 丁选明 刘汉龙 孔纲强 |
| |
| 作者单位： | 1. 河海大学 岩土力学与堤坝工程教育部重点实验室，南京 210098；2. 河海大学岩土工程科学研究所，南京 210098；3. 河海大学 水资源高效利用与工程安全国家工程研究中心，南京210098 |
| |
| 基金项目： | 国家自然科学基金高铁联合基金重点项目资助（No.U1134207）；创新团队；江苏省自然科学基金项目（No.BK20122811）；教育部新世纪优秀人才支持计划。 |
| |
| 摘 要： | PCC桩-网复合地基作为一种新型处理软土路基的结构形式，在软弱土地区高速铁路建设中已获得应用，其在列车激振荷载下的动力特性值得研究。本文确定了合理的列车动荷载加载形式，应用有限元软件ABAQUS建立了轨道-路堤-桩-土复合地基三维动力耦合有限元模型，基于基床、桩、垫层和地基模量参数变化，进行了路堤、桩体以及地基土的动力特性分析。结果表明：PCC桩复合地基动应力响应有别于实心桩，动应力波在管桩中发生反射交叠作用，桩与垫层动力相互作用大于土与垫层动力相互作用。基床表层模量变化对桩-土动力变化影响不大。垫层刚度的增加提高了桩体的动荷载分担比，同时桩顶动应力随着桩与垫层动力相互作用的增强而增大。随着PCC桩模量的提高，动应力在桩体中传播速度加快，动应力增大，使其承担了大部分动荷载，有效地降低了地基土承受的动荷载，同时减弱了上部荷载在复合地基内部影响。随着距离中心桩距离的增大，边桩动应力逐步减小。
|
| 关 键 词： | 高速铁路 列车激振荷载 PCC桩复合地基 ABAQUS 动力有限元分析 |
| 收稿时间： | 2013-03-24 |
Dynamic analysis of PCC pile composite foundation under train vibration load |
| |
| FU Qiang,DING Xuan-ming,LIU Han-long,KONG Gang-qiang.Dynamic analysis of PCC pile composite foundation under train vibration load[J].Rock and Soil Mechanics,2013,34(Z2):413-420. |
| |
| Authors: | FU Qiang DING Xuan-ming LIU Han-long KONG Gang-qiang |
| |
| Institution: | 1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China; 2. Geotechnical Research Institute, Hohai University, Nanjing 210098, China; 3. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety, Hohai University, Nanjing 210098, China |
| |
| Abstract: | As a new type structure form in soft soil foundation treatment, PCC pile-net composite foundation has been used in high speed railway construction in soft soil area. The dynamic characteristics of PPC pile composite foundation under the train vibration load is worth studying. A reasonable train dynamic loading form is determined in this paper. A three-dimensional dynamic coupling finite element model of tracks-embankment-pile-soil composite foundation is established using software ABAQUS. The dynamic characteristics of embankment, pile and foundation soil are studied based on the modulus changes of foundation bed, pile, cushion layer and foundation. The results show that the dynamic response of PCC pile composite foundation is different from the solid pile; the reflection overlap effect of dynamic stress occurs in the pile. The dynamic interaction of pile and cushion layer is greater than that of soil and cushion layer. The modulus changes of foundation bed don’t affect the dynamic stress of pile-soil seriously. The dynamic load sharing ratio of the pile body increases with the increasing of the cushion stiffness. Meanwhile, the increase in modulus of the cushion enhances the dynamic stress of the pile top, which is due to dynamic deformation coordination occurring between piles and cushion. The increase in modulus of the pile enhances the dynamic stress of the pile and increases the propagation speed of dynamic stress. The PCC pile can bear most of the dynamic load and reduce the dynamic load of the soil, thus reduce the influence of upper load on composite foundation effectively. As the distance increases with the center pile, the dynamic stress of the side pile decreases. |
| |
| Keywords: | high speed railway train vibration load PCC pile composite foundation ABAQUS dynamic finite element analysis |
|
| 点击此处可从《岩土力学》浏览原始摘要信息 |
| 点击此处可从《岩土力学》下载免费的PDF全文 |
