基于视频图像技术的简支梁动静载试验分析

Analysis of Static and Dynamic Load Test of Simply Supported Beam based on Video Image Technology

针对简支梁的试验模型,与传统的动载和静载试验不用,采用了视频图像技术来对简支梁的振动进行模态分析。一共进行了两组模型试验,分别为带传感器和不带传感器下的简支梁模型。并采用Matlab软件把简支梁的振动视频分解成图像,对分解得到的图像裁剪出感兴趣区域进行灰度化和二值化处理。为了精确,对得到的整像素边缘进行了亚像素化处理,并处理出梁下边缘的亚像素级别的时域信号。对这些信号数据进行模态分析得出前三阶频率和振型,并与Midas建立的有限元模型,传统的动载试验处理得到的结果三者相比对,论证视频图像技术在动静载试验中的可行性和精确性。经两组试验对比论证,基于视频图像技术的动静载检测较传统检测有更高的精度和可操作性,可以弥补传统检测的不足之处。

According to the experimental model of simply supported beam,compared with the traditional dynamic load and static load tests,the new video image technology is used to analyze the vibration of the simply supported beam.Two groups of model tests are carried out,which are the simple supported beam model with the sensors and without the sensors.The Matlab software is used to decompose the vibration video of the simply supported beam into images,and the region of interest is cut out to do the graying and binarizing processing.In order to be accurate,the sub-pixel edge of the integer-pixel edge is processed by sub-pixel and obtaining sub-pixel-level domain signal.Three frequencies and mode shapes are obtained by modal analysis,compared with the finite element model established by Midas,the results of the traditional dynamic load test to prove the feasibility and accuracy of video image technology in dynamic and static load test.Based on the comparison of two groups of experiments,the dynamic and static load detection based on video image technology has higher precision and maneuverability than traditional detection and it can make up for the shortcomings of traditional detections.