PhD student presents wind and bridge engineering research at international conference

Real-Time Aerodynamics Hybrid Simulation: A Novel Wind-Tunnel for Flexible Bridges (RTAHS) is a research topic carried out by Li under the supervision of Wu and Mettupalayam Sivaselvan, a bridge and structural engineering and computational engineering mechanics associate professor. RTAHS addresses some of the issues with conventional scaled model tests of full-span bridge models in wind tunnels.

“Currently, the full-span bridge model tests in the wind tunnel are still a final check for long span flexible bridges,” Li says, “because of the small scaling ratio, it is difficult for the models to accurately capture structural properties.”

In order to enhance the performance of conventional wind tunnel tests, Li, Wu and Sivaselvan developed an RTAHS. Their simulation divides the bridge model into two substructures: the “skin model,” consists of the bridge deck and captures the aerodynamic properties, and the “skeleton model,” captures the structural dynamic properties, including cables, hangers and pylons.

The skin and skeleton interact through a system of sensors, electromagnetic actuators and controllers. “The current scaled models can only accurately simulate the first two or three lower modes,” Li says, “RTAHS will be able to accurately simulate higher modes throughout the entire test.”

“EMI is the prime venue for disseminating progress in engineering mechanics,” Wu says. The conference took place at the Massachusetts Institute of Technology in 2018.

“The feasibility of RTAHS methodology is demonstrated by the numerical example in our work,” Li says, “hopefully the RTAHS will be in wind tunnels is in the near future.”