【作者】 张敏；

【导师】 张俊云；

【作者基本信息】 西南交通大学 ， 建筑与土木工程（专业学位）， 2018， 硕士

【摘要】 经过多年运营,多数既有线铁路存在不同程度的病害,主要病害表现为路基下沉现象,同时对于处于季节性冻土区域的既有线,均在春融期出现不同程度的翻浆冒泥、不均匀冻胀变形等现象。列车经过引起的强迫振动是导致路基病害的主要因素,本文以既有线路基整治工程为工程背景,研究既有线的路基动力响应,以及病害路基的振动检测方法,取得的主要成果有:1.为了研究季节性冻土区铁路路基在不同时期振动特性,针对典型季节性冻土区宝中铁路线分别在冻结期和正常期进行了行驶列车经过时引起的的路基振动加速度的现场监测,得到了不同时期填方路基道砟旁、坡脚处三个方向的振动加速度响应变化规律。2.结合工程现场路基整治工程,选取典型路堤断面,对既有线重载低速铁路路基沿路基深处的动力响应进行了研究,得到相应的振动加速度响应时程曲线以及路基振动响应沿路基深度的衰减规律。3.通过对路基加固前后以及已加固段、未加固段振动响应的监测分析,提出了病害路基振动响应检测方法,确定了振动加速度、振动速度、动位移作为路基振动检测指标。4.结合大准铁路病害整治工程,对该既有线病害路基进行了振动检测,得出了不同路基的振动加速度、振动速度、动位移响应,总结提出了具体的病害路基振动响应检测方法以及路基是否为病害路基的判断方法。更多还原

【Abstract】 After many years of operation,most of the existing railway lines have different degrees of disease,and the main disease is subgrade subsidence.At the same time,for the existing lines in the seasonally frozen regions,there are different degrees of mud-slurry,uneven frost heave deformation,etc.during the spring period.The forced vibration caused by train passes is the main factor that causes the disease of the subgrade.This paper takes the existing line-based regulation project as the engineering background,studies the dynamic response of the subgrade of the existing railway,and the vibration detection method of the disease roadbed.The main achievements are:1.In order to study the vibration characteristics of railway subgrade at different periods in seasonal frozen soil area,the on-site monitoring of the subgrade vibration acceleration caused by the passing of trains during the frozen period and normal period of the Baozhong railway line in a typical seasonal frozen area,the law of vibration acceleration response in three directions of roadbed and side slope of embankment in different periods is obtained.2.Combined with the roadbed regulation works of the engineering site,the typical embankment sections are selected to study the dynamic response of the heavy haul and low-speed Railway Subgrade along the deep roadbed.The corresponding vibration acceleration response time history curve and the attenuation law of roadbed vibration response along the roadbed depth are obtained.3.Through monitoring and analyzing the vibration response of railway subgrade before and after reinforcement and reinforced section and unreinforced section,a method for detecting the vibration response of the disease subgrade is proposed,vibration acceleration,vibration speed,and dynamic displacement were determined as indicators for the detection of subgrade vibration.4.Combined with the disease control project of the Da Zhun railway,the vibration detection of the existing roadbed is carried out.The vibration acceleration,vibration velocity and dynamic displacement response of different roadbeds are obtained.Summarizes a specific method for detecting the vibration response of diseased roadbed and whether the roadbed is a method to determine the roadbed of disease.更多还原