Internal force monitoring and estimation of a long‐span ring beam using long‐gauge strain sensing

Abstract

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.

Full-field static and dynamic strain measurement by an inverse conjugate beam method with two-type sensor placement

“…L is the length of the sensing unit, and θ o (t) and θ p (t) refer to the angle degrees of freedom of nodes o and p, respectively, at both ends of the sensing unit at time t. These sensors provide static and dynamic strain outputs encompassing both local and global structural information, making them a popular choice for health monitoring in large civil structures [35][36][37][38].…”

Moving Load Identification with Long Gauge Fiber Optic Strain Sensing

“…As mentioned previously, most strain sensors used for moving load identification described in the literature are point-type sensors, which are too local to reveal inherent structural characteristics. Even the widely used FBG-based strain sensor characterized by such promising features as high precision level, stable sensing capacity and reliability (Bocciolone et al, 2013;Zhang et al, 2015;Zhang et al, 2020) is still categorized into the group of point sensors due to its short gauge length. The recently developed distributed sensing technologies such as the Brillouin Optical Time Domain Reflectometry (BOTDR) also have limited properties and high costs.…”

Novel measurement method for full-field bridge strain and displacement with limited long-gauge strain sensors

“…Nowadays, FBG strain sensors have many noteworthy advantages, including multiplexing capability, high sampling rates, and immunity to optical and electromagnetic interference [32][33][34]. A long-gauge FBG sensor was developed to measure average strain over an extended gauge length of 1-2 m [35][36][37]. These sensors provide dynamic strain outputs encompassing both local and global structural information, making them a popular choice for health monitoring in large civil structures.…”