【作者】 刘立；

【导师】 胡庆武；

【作者基本信息】 武汉大学 ， 摄影测量与遥感， 2017， 硕士

【摘要】 铁路隧道拱顶沉降指隧道基于拱架结构主体上连续的半圆拱结构的下沉。近年来,我国科技和经济的发展不断推动着铁路隧道的快速建设,铁路线路逐年增多,火车运行不断提速,这要求铁路隧道拱顶沉降监测的效率和精度应该不断提高。目前国内外已有多种隧道拱顶沉降监测的方法,但由于这些方法自身的局限性,使得它们无法满足当前不断增多的隧道拱顶沉降监测要求。全站仪与反射标靶相结合测量固定点从而获取隧道断面的方法,数据密度低、采集速度慢、人力消耗大;数字摄影测量通过影像配准、定向等数字图像数据处理流程可以较快获得隧道三维数据,但是该方法要求照明条件好,因此限制了该方法在隧道中的应用;传感器测量通过在隧道中放置位移计、收敛计等来测量固定点的相对沉降量,但是只能监测单个固定点,无法分析整个断面的沉降量,费时费力;隧道沉降检测车可以实时、快速获得等间隔隧道横断面,但由于造价问题,在我国生产应用的数量并不多。地面三维激光扫描通过远距离非被动测量方式获取被测物体的点云,具有高速、高精度、高密度、不受时间限制等优点,而且测距长。利用地面三维激光扫描仪获取隧道点云,可以夜间作业,测站布设少,数据获取快,本文研究基于地面激光扫描点云数据的隧道拱顶沉降监测方法,研究的主要内容如下:1)研究目前隧道拱顶沉降监测方法的原理,结合地面三维激光扫描数据的特点,研究将地面三维激光扫描数据与隧道拱顶沉降监测相结合的方法,整理出基于地面激光扫描的铁路隧道拱顶沉降监测的技术流程和框架。2)结合隧道的结构和特点,研究面向铁路隧道沉降监测的地面激光扫描点云预处理方法,研究合理架设测站、布设标靶并对隧道点云中的冗余信息进行有针对性的过滤,从而精简点云数据、提高数据精度的方法;研究基于全景影像和点云的由粗到精的配准方法。3)提出单站铁路隧道点云的拱顶沉降计算与定位方法,首先是断面提取与各个断面沉降分析,通过建立坐标系提取断面,根据点云切片确定各点高程值和沉降量;通过三次样条曲线插值拟合处理断面上的离散点集,提高离散点密度;通过分段采用不同窗口的中值滤波算法平滑曲线;通过求曲线的导数极值点找出沉降最大值所在区间范围。其次是基于单站密集断面构TIN进行单站拱顶沉降分析,再通过构TIN和填挖方实现单站拱顶沉降分析和可视化。4)通过两个实验验证了本文的方法,本文实验证明基于三维激光扫描的铁路隧道拱顶沉降监测方法行之有效。更多还原

【Abstract】 The railway tunnel vault settlement refers to the settlement of continuous half-circle vault based on the main arch structure of tunnel.In recent years,Chinese technology and economic development continue to promote the rapid construction of railway tunnels,railway lines increased year by year,the train running speed,which requires the railway tunnel vault settlement monitoring efficiency and quality should continue to improve.At present,there are a variety of tunnel vault settlement monitoring methods at home and abroad,but because of the limitations of these methods,they can not meet the current increasing demand for tunnel dome settlement monitoring.The data density is low,the acquisition speed is slow and the human consumption is large.The digital photogrammetry can obtain the digital image data processing process through image registration and orientation.The digital image data can be obtained by the combination of the total station and the reflection target.Tunneling three-dimensional data,but the method requires good lighting conditions,thus limiting the application of the method in the tunnel;sensor measurement by placing a displacement meter in the tunnel,convergence meter to measure the relative settlement of fixed points,but can only monitor a single Fixed point,can not analyze the settlement of the entire section,time-consuming and laborious;tunnel settlement detection vehicle can be real-time,fast access to equal spacing tunnel cross-section,but because of the cost of production in China,the number of production applications is not much.The three-dimensional laser scanning of the ground can obtain the point cloud of the measured object through the long-distance non-passive measurement method.It has the advantages of high speed,high precision,high density,no time limit and so on.This paper studies the method of monitoring the tunnel dome settlement based on the ground laser scanning point cloud data.The main contents of the study are as follows:The method of monitoring the tunnel dome based on the ground laser scanning point cloud data is as follows:1)This paper studies the principle of monitoring method of tunnel vault settlement,combined with the characteristics of 3D laser scanning data of the ground,and studies the method of combining the three-dimensional laser scanning data of the ground with the monitoring of the tunnel vault to sort out the railway tunnel arch based on the ground laser scanning Technology and framework for monitoring of top settlement.2)Combining the structure and characteristics of the tunnel,the study of the ground laser scanning point cloud for the boundary detection of railway tunnels Segment preprocessing method to study the rational design of the station,laying the target and the tunnel point cloud redundant information in the targeted filtering,thus streamlining the point cloud data to improve the data accuracy method;study based on panoramic images and point cloud From coarse to fine registration method.3)The method of calculating the settlement of the dome of single-station railway tunnel is proposed.First,Surface subsidence analysis,by establishing the coordinate system to extract the cross section,according to the point cloud slices to determine the elevation and settlement of the points;through the cubic spline interpolation method to deal with the discrete points on the cross-section to improve the discrete point density;Window median filter algorithm smooth curve;by asking the derivative of the curve to find the range of extreme points.Secondly,the single station dome settlement analysis is carried out based on single station dense cross section TIN.The discrete point set filter is realized by grid filter based on mathematical morphology,and the single station vault settlement analysis and visualization are realized by constructing TIN and filling.4)Verify the approach proposed in this paper by two experiments,and these experiments show that the monitoring method of railway tunnel vault settlement based on 3D terrestrial laser scanning is effective.更多还原