In the field of bridge structural system identification (SSI), Bernoulli beam element models are often used to solve inverse problems. More rarely, Timoshenko beam element models can be calibrated. However, these models account for only the general shear effects, whereas other shear effects, such as shear lag, are not accounted for. However, as wide-flange box girder bridges become prevalent due to design demands, neglecting shear lag may introduce significant errors in predicting the mechanical parameters of the system and, hence, reduce the accuracy. In this paper, for the first time, the shear lag's effect on the vertical deflections is taken into account in an inverse problem. A parametric SSI, the observability method (OM), is updated to address the identification of thin-walled box girder bridges with wide flanges, including the shear lag effects. The structural analytical equations are used to connect the spatial shear effects with the beam-unidimensional-element model to be applied in the inverse analysis, which is referred to as the analytical observability method (AOM-SSI). This updated version of the OM is established and validated to identify the mechanical parameters of a structural test. The identified mechanical parameters show much better agreement with the expected results than those obtained with previous methods.

在桥梁结构系统识别（SSI）领域，伯努利梁单元模型常用于求解逆问题。更罕见的是，可以校准 Timoshenko 梁单元模型。然而，这些模型只考虑了一般的剪切效应，而没有考虑其他剪切效应，例如剪切滞后。然而，由于设计要求，宽翼缘箱梁桥变得普遍，忽略剪力滞可能会在预测系统的力学参数时引入重大误差，从而降低精度。在本文中，第一次在反问题中考虑了剪力滞对竖向挠度的影响。更新了参数 SSI，即可观察性方法 (OM)，以解决具有宽翼缘的薄壁箱梁桥的识别问题，包括剪力滞效应。结构解析方程用于将空间剪切效应与梁一维元模型应用于逆分析，称为解析可观测性方法（AOM-SSI）。已建立并验证此更新版本的 OM，以识别结构测试的机械参数。与以前的方法获得的结果相比，确定的机械参数与预期结果的一致性要好得多。已建立并验证此更新版本的 OM，以识别结构测试的机械参数。与以前的方法获得的结果相比，确定的机械参数与预期结果的一致性要好得多。已建立并验证此更新版本的 OM，以识别结构测试的机械参数。与以前的方法获得的结果相比，确定的机械参数与预期结果的一致性要好得多。