考虑空间地形效应的山区高速铁路桩基-地基耦合振动响应机理研究

The high-speed railway construction is rapidly developing towards central and western China, where is mostly mountain area. The topography and geological conditions in mountain area are complicated, which brings new challenge to the construction technique and design theory of the high-speed railway. The objective of this project is to study the pile-soil coupled vibration and load transfer mechanism of high-speed railway in complex soil in mountain area considering topography effects, based on model test, numerical simulation and theoritical analysis. The following studies are included in this project: the static and dynamic bearing characteristics pile and coupled vibration regularity of pile and soil of high-speed railway by model test and numerical simultation; theoritical analysis on the coupled vibraiton between single piles and pile groups with complex soil by considering topography effects; calculating method of the coupled vibration response of the pile-soil-track sturcture-train system in mountain area subjected to high-speed train loading. The achievements of this project may provide guidelines for design, construction and safety maintenance of high-speed railway in mountain area.

我国高速铁路建设正快速向中西部山区发展，而山区地形地质条件极为复杂，给高速铁路建设技术与设计计算理论带来了新的挑战。本课题拟采用模型试验、数值模拟和理论分析等手段对山区复杂地形中高速铁路桩基-地基的耦合振动响应和动荷载传递机理开展研究。通过开展复杂地形中桩基动力加载模型试验和数值模拟研究，得到山区复杂地形中高速铁路桩基受力特性和桩基-地基耦合振动响应规律，揭示桩基-地基动荷载传递机理；建立考虑空间地形效应的复杂地形中单桩及群桩与地基耦合振动响应理论，得到桩基-地基耦合系统的复动刚度等特性；提出高速列车移动荷载作用下山区高速铁路桩基-地基-轨道结构-列车耦合振动响应分析方法，揭示列车车速与动力响应的关系以及对运营安全的影响。通过本项目的研究，达到为山区复杂地形中高速铁路路基设计、施工和安全运营维护提供科学依据的目的。

山区地形地质条件极为复杂，给我国中西部地区高速铁路建设技术与设计计算理论带来了新的挑战。本项目通过模型试验、数值模拟和理论分析的方法，开展了以下研究：开展了循环荷载作用下斜坡地形和倾斜基岩场地中的单桩、群桩动力特性模型试验和数值模拟研究，揭示了倾斜地层桩基在不同循环周次、不同动力幅值以及不同加载频率等竖向循环荷载作用下的动力响应特性和荷载传递机理；开展了斜坡场地条件下群桩动力响应理论研究，推导了考虑地形影响的桩-桩相互作用因子，揭示了斜坡场地条件下桩-土-桩动力相互作用机理，得到了斜坡场地条件下群桩竖向动力阻抗计算方法；开展了高速列车移动荷载作用下高速铁路桩基-地基-路堤结构耦合系统动力响应数值模拟研究，揭示了高速铁路桩-土-上部路堤结构振动响应特性、荷载传递机理。研究成果为山区高速铁路路基的设计、施工和安全运营提供了科学依据。依托该项目，发表学术论文24篇，其中SCI检索20篇，EI检索3篇，获得发明专利授权8项，培养博士生2名，培养硕士生4名。