基于高精度模态环境振动测试及导入最佳平差参数的桥梁在线抗弯刚度识别方法

提出了一种基于高精度低阶测试模态对桥梁构件抗弯刚度通过导入最佳参数进行平差的最小二乘解识别方法。通过对混凝土试验梁及一座3跨变截面连续箱梁抗弯刚度现场检测及数值模拟计算，结果表明，此方法有效地抑制了模态振型测试误差对识别精度的过度影响，即使对1．5％的锯齿形严重模态振型误差及20％的偶然模态振型误差，识别精度都在6％左右，较好地满足工程精度要求。此外，通过多例模拟数值计算表明锯齿形模态振型误差可作为识别精度的控制性误差。

On-line Identification of Flexural Rigidity Modal for Bridge Structural Members Based on Accurate Modal Test of Ambient Vibration and Best Parameter Adjustment

A least-squares solutions method with best parameter adjustment of flexural rigidity identification for bridge structural members is developed by using measured modes. The result of numerical identification for concrete experimental beam and full-scale three-span continuous beam shows that the introduction of the parameter adjustment is very important for reducing the effect of measurement error on identified result. Also the problem for excessive great effect of mode shape error on identified accuracy can be quite satisfactorily solved using this method.