I 摘要 Google Earth 数据在道路工程可行性研究阶段中的应用 改革开放以来，中国的交通事业得到大力支持并快速发展，2016 年交通基础设施 投资将超过 2.6 万亿。目前，我国公路网络已经基本形成，但还存在着总量不足和结构 矛盾等突出问题，到 2030 年，还有 2.6 万公里国家高速公路待建，还有 10 万公里国省 干线公路需要改造升级，可见道路工程项目一直有巨大的数量，并且需要更多的投资 额。为了工程项目建设的科学决策，可行性研究是道路工程中的重要一环。外业勘测 是编制工程可行性研究报告中的一个重要的步骤，这阶段中，一般采用比例尺是 1:10000 的地形图，外业勘测深度过深则会造成浪费资源，过浅则不满足要求。通常采 用航空摄影技术进行测绘，但其缺点是费用高（800-1000 元/ 2 km ），受天气影响。若 全部使用 GPS 技术进行测量，在地形复杂的区域导致工作艰难，人力消耗很大。为了 使地形图测绘更简便、经济，研究利用 Google Earth 数据帮助测绘制图有重要的现实 意义，并在此基础上利用 Auto CAD Civil3D 帮助进行三维可视化设计。 本文以中国某地区经实地勘测的数字地形图为依据，利用 Google Earth 的地面高 程数据与 Auto CAD Civil 3D 结合进行数字地形图制作和三维道路设计，主要用于道路 勘测设计的可行性研究阶段。为了确保 Google Earth 的高程精度满足实际工程使用要 求，并且可以实际地用于道路设计，本文以 Google Earth 的地面高程精度、提高 Google Earth 高程精度的方法和 Google Earth 数据在道路勘测工程中的使用方法为主要研究对 象，主要研究内容为： （1）研究 Google Earth 数据的来源和高程系统，以实际工程的数字地形图高程数 据和 Google Earth 上的高程数据作对比分析，确定 Google Earth 高程与实际工程高程的 误差。 （2）与高程异常拟合研究类比，研究二次多项式曲面拟合、三次多项式曲面拟合、 Matlab的V4插值法和神经网络法在建立Google Earth数据与实测数据之间高程差模型 的优劣。 （3）研究提高精度后的 Google Earth 地面高程数据能否用于道路工程可行性研究 阶段，能用的数据是否有局限性； （4）研究通过 Google Earth 和 Auto CAD Civil3D 结合，进行三维地形建模和三维吉林大学硕士学位报告 II 道路设计的步骤和优势，发挥 Google Earth 的实用性和为道路工程设计提供简便的方 法。 研究结论：Google Earth 高程数据的来源是 STRM-3 数据，与我国工程所用的正常 高之间存在着高于 1:10000 地形图允许的误差；建立地面高程差的拟合或插值模型， 灵活使用三次多项式曲面模型和神经网络法进行拟合是合理的选择，能有效预测模型 中各个地方的高程差，大幅度提高 Google Earth 高程精度；以中国某地区的 Google Earth 数据为例，提高精度后，平地地形区域的 Google Earth 数据仍不满足 1:10000 地形图 的要求，丘陵地区区域的 Google Earth 数据可以满足要求；Google Earth 和 Auto CAD Civil3D 可以简单有效地结合，给可行性研究中的道路勘测设计和展示提供更简便、生 动具体的设计流程和方法。 综上所述，本文的研究可以使道路工程可行性研究阶段中的勘测设计更便捷、更 经济，显著提高 Google Earth 地面高程数据用于实际工程中的精度，并且为道路勘测 设计的发展趋势提供了一定参考。 关键词： Google Earth，道路工程，可行性研究，高程精度分析，高程拟合，三维设计Abstract III Abstract Application of Google Earth’s Data in Feasibility Study Stage of Road Engineering Since the reform and opening up, China's transportation has been vigorously supported and developed rapidly.In 2016, the transportation infrastructure investment exceeded 2 trillion and 600 billion. At present, our country's road network has basically formed, but there still exist some problems, such as insufficiency of total and structural contradiction. In 2030, there are 26 thousand kilometers' national highway to build, and 100 thousand kilometers' national and provincial trunk highways to reform and upgrade. It can be seen that the road engineering projects are huge in quantity and require more investment. In order to make scientific decision for engineering project construction, the feasibility study is an important part of road engineering. Outdoor surveying is an important step for working out the feasibility study report of project, in this stage, topographic maps of which scale are 1:10000 are generally used and usually mapped with aerial photography technology. Too much outdoor surveying will lead to waste of resources, but too little will not meet the requirements. Aerial photogrammetry is usually used for surveying and mapping, but its disadvantages are high cost (800-1000 yuan / 2 km ) and easy to affect by the weather. If entirely using GPS technique to measure , it can be difficult to work in complex terrain, and cost of manpower is great. There is a huge amount of money, and more investment is needed. In order to make mapping simpler and more economic, research on using data of Google Earth to help surveying and mapping has important practical significance. And on this basis, usingAutoCADCivil3D to help 3D visualization design. In this paper, based on the digital topographic map of a region in China from field surveying, use modified ground elevation data of Google Earth combined with AutoCADCivil3D to make digital topographic map and design 3D road, which are mainly used in the feasibility study stage of road survey and design. In order to ensure the height accuracy of Google Earth can meet the requirements of actual project, and can be practically used in road design. This article takes the ground elevation data of Google Earth, method of improving height accuracy of Google Earth and application of Google Earth data in road survey engineering as the main study object, the main research contents are as follows: （1）Study the source and elevation system of Google Earth data, make a comparison吉林大学硕士学位报告 IV between the elevation data of actual engineering digital topographic map and the elevation data of Google Earth to determine the error between the Google Earth elevation and the actual engineering elevation. （2）Analogy with the elevation anomaly fitting, study the good and bad points of quadratic polynomial surface fitting, cubic polynomial surface fitting and Matlab V4 interpolation and neural network in establishing elevation error model between the data of Google Earth and the measured data. （3）Study whether the modified ground elevation data of Google Earth can be used in the the feasibility study stage of road engineering and whether the modified data will be limited. （4）Study the steps and advantage 3D terrain modeling and 3D road design, through the combination of Google Earth and Auto CAD Civil 3D,the practicability of Google Earth is brought into platy and the simple method for road engineering design are provided. The research conclusion: the source of Google Earth elevation data is STRM-3 data, which has an error higher than the allowable error of 1:10000 topographic maps between the normal elevation used in our country’s project; To build a fitting or interpolation model of ground elevation error , the flexible use of cubic polynomial surface fitting model and neural network method for fitting is a reasonable choice, which can effectively forecast the elevation error everywhere in the model, greatly improve the precision of Google Earth elevation; Take Google Earth data somewhere in China as an example, after improving the accuracy, the Google Earth data of flat terrain area can still not meet the requirements of 1:10000 topographic map, but the Google Earth data of hilly terrain area can meet the requirements; Google Earth and Auto CAD Civil 3D can be simply and effectively combined to provide a more convenient, vivid and specific design process and method for road survey, design and display in the feasibility study. In summary, this study can make the survey and design of feasibility study stage of road engineering more convenient and more economical, significantly improve the accuracy of Google Earth ground elevation data for actual engineering, and provide a reference for the development trend of road survey and design. Keywords: Google Earth，Road Engineering，Feasibility Study，Analysis of height accuracy，Height fitting，3D design目录 V 目录 第 1 章绪论...........................................................................................................1 1.1 报告选题的背景和意义.......................................................................... 1 1.2 国内外研究现状..................................