装配式钢混组合梁全息图像拼接方法试验研究

Experimental Study on the Holographic Image Mosaic Method of Prefabricate Steel-concrete Composite Beam

针对传统桥梁监测方法存在测点数量有限的问题,提出一种通过摄影测量手段获取桥梁全息几何形态信息的方法,以进行对全桥任意点变形监测。首先,采用形态图像数据采集系统获取试验梁具有重复区域连续照片;然后,基于改进后尺寸不变特征变换(scale invariant feature transform,SIFT)算法对连续图片进行拼接可得试验梁全息图片,进而获取试验梁全息几何形态;最后,基于全息形态位移信息追踪算法提取试验梁各工况下的全息变形曲线。通过与传统位移计测量结果和基于SIFT算法拼接而得位移结果进行对比发现:基于改进后SIFT算法实现的拼接图像包含信息丰富,可为大尺度结构大视场应用情况下全息几何形态监测奠定基础。

Aiming at the problem of the limited number of measuring points in traditional bridge monitoring methods,a method for obtaining holographic geometric information of bridges through photogrammetry was proposed to realize the monitoring of arbitrary point displacement of the whole bridge.Firstly,the morphological image data acquisition system was used to obtain continuous photos of the test beam with repeated regions.Then,the continuous pictures were stitched based on the improved SIFT(scale invariant feature transform)algorithm to obtain the test beam hologram.Furthermore,the holographic deformation curve of each test beam was extracted.By comparing with the displacement results obtained from the traditional displacement meter measurement and the SIFT algorithm,it is found that the stitched image based on the improved SIFT algorithm contains rich information,which can lay a good foundation for the monitoring of holographic geometry in the application of large-scale structures and large fields of view.