Double-layer model updating for steel-concrete composite beam cable-stayed bridge based on GPS

作者：Liu Yun^*; Qian Zhendong

来源：Journal of Southeast University (english Edition), 2008, 24(1): 80-84.

• Double layer model updating
• Finite element iteration algorithm
• First layer model updating
• Integral structure stiffness
• Long span bridges
• Manual tuning technique
• Nanpu Bridge
• Second layer model updating
• Steel-concrete composite beam

In order to establish the relationship between the measured dynamic response and the health status of long-span bridges, a double-layer model updating method for steel-concrete composite beam cable-stayed bridges is proposed. Measured frequencies are selected as the first-layer reference data, and the mass of the bridge deck, the grid density, the modulus of concrete and the ballast on the side span are modified by using a manual tuning technique. Measured global positioning system (GPS) data is selected as the second-layer reference data, and the degradation of the integral structure stiffness EI of the whole bridge is taken into account for the second-layer model updating by using the finite element iteration algorithm. The Nanpu Bridge in Shanghai is taken as a case to verify the applicability of the proposed model updating method. After the first-layer model updating, the standard deviation of modal frequencies is smaller than 7%. After the second-layer model updating, the error of the deflection of the mid-span is smaller than 10%. The integral structure stiffness of the whole bridge decreases about 20%. The research results show a good agreement between the calculated response and the measured response.

• 出版日期2008
• 单位东南大学