Collaborative Research: Coupled Hydro-structural Mechanics of Non-rigid Floating Bodies under Quasi-standing and Breaking Waves

Floating infrastructure, including buildings, bridges, breakwaters, renewable energy platforms, and aquaculture facilities, offers a sustainable alternative to land reclamation while helping communities adapt to the increasing severity of coastal hazards. However, current engineering practice often treats floating structures as rigid bodies subjected mainly to non-breaking waves, thus overlooking the intense impact forces generated by breaking waves and the inherent flexibility of the structures they support. This research will generate the fundamental knowledge needed to understand how realistic non-rigid floating structures respond to both ordinary and extreme wave conditions, thereby enabling safer coastal/ocean systems and communities. The project will advance the science of wave-floating structure interaction, provide openly accessible experimental datasets and computational tools, and establish engineering guidance for the next generation of floating infrastructure. In addition, the research will support the training of graduate and undergraduate students in interdisciplinary structural, coastal, and ocean engineering, engage K-12 students and the public through hands-on outreach activities and laboratory demonstrations, while strengthening U.S. leadership in marine infrastructure, offshore renewable energy, and coastal resilience. The overarching objective of this project is to elucidate the multi-phase and multi-scale mechanics of compliantly moored floating pontoons supporting an idealized lumped mass with tunable natural periods excited by non-breaking and breaking waves. In doing so, the researchers address a central hypothesis: that the system level performance of a floating structure will strongly depend on the dynamic properties of its inherently flexible superstructure (i.e., natural period of vibration), particularly under impulsive breaking waves. The project combines large-scale experiments, computational fluid dynamics (CFD) coupled with structural simulations, analytical mechanics, and data-driven methods to quantify wave-floating structure interaction under diverse wave conditions, including the dimensional scaling of both hydrodynamic and structural phenomena in the context of fixed and floating systems. Unique insights into overtopping discharge and the role of wave groupiness will additionally be revealed due to their importance on floating systems. These developments will be leveraged to advance the state-of-the-art in CFD to enable the simulation of non-rigid floating structures subjected to breaking wave excitation within a Lagrangian framework. Experimental and numerical results will be further augmented by advanced machine learning methods to develop novel response spectra that predict the dynamic behavior of generalized floating bodies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.