桥墩冲刷坑形态试验测绘新方法

A new method of pier scour test surveying and mapping

桥墩冲刷试验中冲刷坑测量是试验的关键步骤,传统人工标尺测量方式具有测量费时、数据处理繁杂、易破坏地形等不足。文章引入倾斜摄影技术,提出了能够快速准确测量桥墩冲刷试验冲刷坑的新方式——摄影测量,完成了桥墩冲刷试验中冲刷坑三维形态快速重建,实现了三维地形实景模型向地形等高线图的转化,提取了试验桩周冲刷坑的冲刷深度。研究结果表明:(1)摄影测量在满足精度要求的同时,可大幅缩短冲刷试验测量的时间成本;(2)冲刷坑三维形态重建模型能够快速转换成地形等高线图,可直观表示冲刷坑的形态,网格等高线图采用线性内差可快速得出冲刷坑重建区每一点的冲刷深度,相较于人工标尺测量数据再处理得到的冲刷坑形态更加形象,测量方式更加简便。

The scour pit measurement is a key step in the bridge pier scour experiment.The traditional manual scale measurement method has the disadvantages of time-consuming,complicated data processing,and easily causing the scour terrain damage.In this paper,the oblique photography technology was introduced,and a new method based on photogrammetry was proposed,which can quickly and accurately measure the scour pit in the scouring experiment of the bridge pier.The 3D model of the scour pit in the pier scour experiment was restored,the 3D terrain real scene model was transformed to the terrain contour map,and the scour depth of the scour pit around the piles was extracted.The research results show that:(1)photogrammetry can significantly shorten the time cost of scour experiment measurement while satisfying accuracy requirements;(2)the three-dimensional model of the scour pit can be conveniently converted into a topographic contour map,which can visually represent the pattern of the scour pit.The scour depth at each point in the scour pit can be quickly read on grid contour map by using linear interpolation method.Compared with the traditional manual measurement,photogrammetry could obtain the scour pit pattern much more vivid with simpler operation.