The internal force information of curved beam members is important evidence for the stress state evaluation and design verification of long‐span space structure during construction. Many structural analysis methods for curved beams have been proposed, but most are used to handle the complex geometric shapes. For stress state evaluation of long‐span steel‐concrete composite (SCC) ring beam, this article presents a method that employs a sectional strain distribution model (SSDM) and a fiber model to estimate the internal force distribution depending on the long‐gauge strain. The SSDM of the ring beam used in the article is based on a mechanical model of two‐dimensional (2‐D) plane bending deformation and a three‐dimensional (3‐D) solid finite element model of curved beam members. The application range of the SSDM is defined by the divided different stress areas of ring beam based on the 3‐D solid finite element model. Combined with the established SSDM and the different stress areas, the axial force and bending moment along the span are then identified separately based on the fiber model. In consideration of field monitoring, the influence of different sensor layout on the establishment of SSDM and the result of internal force identification is discussed. The results of the numerical studies show that the proposed methodology can identify the internal force distribution accurately. Internal force of long‐span ring beam from Jiangsu Grand Theater during construction is also identified through the proposed method by using the strain monitoring data.

中文翻译：

---

大跨度环梁的内力监测和估计

弯梁构件的内力信息是大跨度空间结构施工过程中应力状态评估和设计验证的重要依据。已经提出了许多用于弯曲梁的结构分析方法，但是大多数方法用于处理复杂的几何形状。为了评估大跨度钢-混凝土复合材料（SCC）环形梁的应力状态，本文提出了一种采用截面应变分布模型（SSDM）和纤维模型来根据长规应变估算内力分布的方法。本文中使用的环形梁的SSDM基于二维（2D）平面弯曲变形的力学模型和弯曲梁构件的三维（3D）实体有限元模型。SSDM的应用范围由基于3D固体有限元模型的环形梁的不同应力区域定义。结合已建立的SSDM和不同的应力区域，然后基于纤维模型分别确定沿跨距的轴向力和弯矩。在现场监测的基础上，讨论了不同传感器布局对SSDM建立和内力识别结果的影响。数值研究结果表明，所提出的方法能够准确识别内力分布。该方法还利用应变监测数据，确定了江苏大剧院大跨度环形梁在施工过程中的内力。结合已建立的SSDM和不同的应力区域，然后基于纤维模型分别确定沿跨距的轴向力和弯矩。在现场监测的基础上，讨论了不同传感器布局对SSDM建立和内力识别结果的影响。数值研究结果表明，所提出的方法能够准确识别内力分布。该方法还利用应变监测数据确定了江苏大剧院大跨度环形梁在施工过程中的内力。结合已建立的SSDM和不同的应力区域，然后基于纤维模型分别确定沿跨距的轴向力和弯矩。在现场监测的基础上，讨论了不同传感器布局对SSDM建立和内力识别结果的影响。数值研究结果表明，所提出的方法能够准确识别内力分布。该方法还利用应变监测数据确定了江苏大剧院大跨度环形梁在施工过程中的内力。讨论了不同传感器布局对SSDM建立的影响以及内力识别结果。数值研究结果表明，所提出的方法能够准确识别内力分布。该方法还利用应变监测数据确定了江苏大剧院大跨度环形梁在施工过程中的内力。讨论了不同传感器布局对SSDM建立的影响以及内力识别结果。数值研究结果表明，所提出的方法能够准确识别内力分布。该方法还利用应变监测数据确定了江苏大剧院大跨度环形梁在施工过程中的内力。