基于立体视觉的砌体房屋模型振动试验研究

Research on vibration testing of a masonry building model based on stereovision

针对结构动态响应监测三维变形的需求,研究立体视觉三维测量算法,建立基于结构测面的世界坐标系,得到结构振动响应三维位移公式。研究圆形标识点边缘检测、中心拟合及匹配约束算法,编译基于MATLAB平台的立体视觉结构振动测试分析软件。使用本文集成的立体视觉测量系统完成不同加速度峰值Taft波及El Centro波作用下砌体房屋模型振动台试验,同时测得结构三维位移时程曲线。面内位移时程曲线表明立体视觉方法与位移计数据吻合非常好,证实立体视觉测量方法的有效性。离面位移时程曲线表明砌体房屋模型在地震动作用下发生扭转,且随地震动加速度峰值增大,扭转反应加剧,充分验证立体视觉方法用于监测结构三维振动响应的可靠性及实用性。

To meet the monitoring requirement of three-dimensional deformations for structural dynamic responses, a 3 D deformation measurement algorithm based on stereovision is proposed in this paper. The world coordinate system is established on the measurement surface of the structure, and 3 D displacement equations of structural vibration responses are acquired. The algorithms of edge detection, center fitting and matching constraint are developed for circle identifying point, and the structural vibration analysis imaging processing algorithms with MATLAB. A shaking software of stereovision is compiled on the basis of above table test of masonry building model is performed under Taft and El Centro ground motions for different accelerations with the stereovision measurement system integrated in this paper. The out-of-plane and in-plane displacement time histories are obtained simultaneously. In-plane displacement curves show good agreement between stereovision method and displacement meter, and demonstrating that the former is valid for measuring structural vibration. Out-of-plane displacement curves indicate that the masonry building model twists under earthquake ground motions and the twist responses become stronger, when the peak acceleration of earthquake ground motion increases. The experimental results fully prove that the proposed approach in this paper is reliable and useful for monitoring the structural 3D vibration responses.