Expansion joints of bridges are vulnerable to damage due to the thermal expansion and contraction, vehicle traffic, and so forth. Currently, the temperature–displacement relationship model may be the only qualitative method for condition evaluation of bridge expansion joints using the field monitoring data. The quantitative assessment based on the finite element model updating techniques is heavy computational burden and time consuming. Therefore, a Gaussian process (GP) metamodel‐based model updating method is proposed in this study and performed for the quantitative identification on the boundary condition of the expansion joints of Jiangyin Suspension Bridge using the long‐term displacement and temperature monitoring data. At first, the relationship between the longitudinal boundary stiffness (LBS) and structural temperature is formulated on the basis of thermal effects of the bridge deck. The range of LBS is approximately estimated by the regression coefficients from 1‐year monitoring data and is used as initial bounds for the subsequent model updating procedure. The GP metamodel is formulated to map the relationship between the LBS and the longitudinal displacements under the thermal effects. The LBS identification of the Jiangyin Suspension Bridge is performed within the fast‐running GP metamodel. The results show that the longitudinal displacements using the updated LBS are in good agreement with the measurements, which verifies the effectiveness of GP metamodel‐based model updating method in identifying the LBS of the long‐span suspension bridge.

中文翻译：

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考虑热效应的基于元模型的模型更新对大跨度悬索桥伸缩缝状态分析

由于热膨胀和收缩，车辆通行等等，桥梁的伸缩缝容易受到损坏。目前，温度-位移关系模型可能是使用现场监测数据进行桥梁伸缩缝状态评估的唯一定性方法。基于有限元模型更新技术的定量评估是沉重的计算负担和耗时的。因此，本研究提出了一种基于高斯过程（GP）元模型的模型更新方法，该方法用于利用长期位移和温度监测数据对江阴吊桥伸缩缝边界条件进行定量识别。首先，纵向边界刚度（LBS）与结构温度之间的关系是根据桥面板的热效应来制定的。LBS的范围大致由1年监测数据的回归系数估算，并用作后续模型更新过程的初始范围。GP元模型的制定是为了映射LBS与热效应下的纵向位移之间的关系。江阴吊桥的LBS识别是在快速运行的GP元模型中进行的。结果表明，采用更新后的LBS进行纵向位移与实测值吻合较好，验证了基于GP元模型的模型更新方法在识别大跨度悬索桥LBS方面的有效性。