In-service bridge SHM point arrangement with consideration of structural robustness

Abstract

To date, structural health monitoring (SHM) has been used in several long-span bridges and even some middle-span bridges. Many monitoring sensors are usually arranged based on traditional structural mechanical analysis, such as load tests and engineering experiences. Moreover, several studies have also been carried out to reduce the number of monitoring sensor deployments and improve the pertinence of monitoring sensor arrangements. One example is structural robustness analysis, which can be used to locate the vulnerable and weak parts of a bridge to determine the arrangement of SHM sensors. In this paper, a strain energy index is first proposed to evaluate structural robustness. The universal applicability of the evaluation index is also verified by energy principle, and then this index can be widely accepted for engineering applications. A theoretical numerical simulation of the structural robustness of a simply supported beam subjected to different damage effects is then carried out. Different damage locations, different damage degrees and different moving speeds are considered. With the consideration of the same structural type, an in-service simply supported girder bridge is also presented as the verification case study. The bridge once experienced an explosion caused by a moving fireworks vehicle. The monitoring point arrangement based on load tests and engineering experiences can be verified to be highly consistent with the theoretical numerical simulation result. This study provides a method for the SHM point arrangement of this kind of bridge. The structural robustness strain energy evaluation index is also acceptable for other kinds of bridges. The inconvenience caused by traditional structural analysis, such as the temporary closing of road traffic, can also be greatly reduced.