Experimental and numerical investigation of fairing countermeasure for tsunami forces on three different types of bridge superstructure

Abstract

By extending Wu et al. (2023)'s research of reducing tsunami loads on bridge decks through fairings and openings, this study aims to optimize fairing designs for three typical bridge superstructures, i.e., T-girders, Single-box girders, and Multi-box girders, and assess the effectiveness of fairings in mitigating hydrodynamic forces from extreme waves. A comprehensive methodology including both experimental testing and numerical simulations is adopted and the load reduction capabilities of fairings for bridge girders is evaluated, where an active machine learning model is utilized to identify the optimal fairing configurations for each bridge type. Key findings include: (a) Well-designed fairings can substantially reduce both horizontal and vertical wave loads, simultaneously avoiding potential structural damages from openings; (b) Under the investigated tsunami bore wave conditions, as the incident tsunami bore wave height increases, the horizontal and vertical forces acting on the fairing structures significantly increase, highlighting the importance of considering these loads in the fairing design; and (c) For the studied three bridge deck structures with the same width and height dimensions, the observed variations in the optimal fairing configurations are minimal, indicating a feasible potential for the standardized implementation of fairing in practical engineering.