Waterfront facilities are increasing on coastal area for tourism and residential purposes. Low-pressure storms such as typhoons cause overtopping and damage to facilities. To prevent this, fixed and movable overtopping prevention walls are being installed in Korea. However, fixed overtopping prevention walls are not preferred because they impede the view of the coast. In this study, a multifunctional movable barrier was studied. It is usually used as a tourist pier and is erected when overtopping waves are forecast. To analyze its applicability, hydraulic experiments, structural analysis and experiments, and detailed design were performed. In the hydraulic experiment, the amount of wave overtopping and the wave pressure acting on the barrier were analyzed. And in structural analysis and experiments, performance tests of major members were performed. Finally, a full-scale barrier with a height of 2m was manufactured, and a winch was used to operate it.

The Arecibo Telescope in Puerto Rico collapsed on December 1, 2020. After the incident, Thornton Tomasetti Inc. (TT) was engaged by the Florida Space Institute to conduct a forensic investigation of the root cause of the collapse. An essential focus of the investigation was the impact of wind loads, and particularly of Hurricane Maria in 2017, the strongest hurricane that the telescope had experienced in its service life. Computation fluid dynamic (CFD) analysis is computationally expensive for complex structures or winds with long durations. Conducting this type of analysis may be feasible by involving high-performance computing systems. However, given the scope of the investigation, as well as the limited time and budget, performing such a sophisticated CFD analysis of the telescope subjected to the full hurricane time history was infeasible. TT adopted a cost-effective method to simulate the wind loads on the telescope during Hurricane Maria, and apply those forces to a structural analysis model. A CFD model of the telescope was used to generate wind forces at a constant wind speed, and was validated by previous wind tunnel tests on a physical model of the telescope. The validation shows that the CFD analysis can adequately depict the wind tunnel test results, and that the wind forces can be scaled based on wind speeds. The wind forces from CFD analysis were then scaled to time-varying forces based on the on-site measured wind speeds during Hurricane Maria. The time-varying forces were subsequently applied to a finite element (FE) model of the telescope to evaluate its dynamic response during Hurricane Maria. This presentation provides description of each analysis step, validation of the wind force scaling method, and the telescope’s response to Hurricane Maria. The results show that the forces in the cables supporting the telescope increased 14% during Hurricane Maria.

Several tornado chambers are designed and built all around the world to understand the tornado loading on structures. Each tornado chamber structure is different and behaves differently. Verma and Selvam (2022) classified them into three major categories. To understand further the vortex forming mechanism in different chambers, computational fluid dynamics (CFD) is used. In this study different types of chambers like side opening and top opening are considered for analysis. In addition, different sizes like small aspect ratio of the chamber are also considered. Here aspect ratio is the ratio of height of the inlet (ho) to the radius of the chamber (ro).

When the aspect ratio is much smaller, extensive computer time is needed if it is a time dependent flow. For this steady state solver was also proposed. The steady state solver is based on SIMPLE method and the unsteady solver is based on fractional step method. The performance of these CFD methods will be reported. The computed vortex parameters for different chambers will be presented. Vortex parameters for aspect ratio varying from 0.03 to 1 will be reported. From the analysis, the difference in vortex formation mechanism for different chambers will be illustrated using visualization. The research findings help to understand the vortex formation mechanism and efficient design the tornado chambers in the future.