Ingenious solutions in building science, including the world’s first irregular tuned sloshing damper, give the city of Qingdao a showpiece development
Embraced by sea on three sides, the city of Qingdao’s scenic beauty makes it a prized location for its nine million residents and thriving tourism industry. Amidst this natural splendor and warm hospitality, an impressive development is taking shape as the city’s new jewel. The Qingdao Guoxin Haitian Project is a world-class mini-city comprising three towers that include hotels, offices, retail and residential areas, a museum, and a 360-degree observation deck with stunning views in all directions. The 369-meter, 73-story Tower 2, which houses the Qingdao Haitian Hotel, is Shandong province’s tallest tower.
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The Challenge
Enormous expectations from the developer, citizens, and prospective tenants made it critical that every facet of the highly anticipated complex be a success. Wind effects on the building’s soaring height can create “sway,” which must be contained to conform to regulatory requirements and safeguard occupant comfort. The fact that the project is located in a typhoon region further complicated matters. The developer’s goal to achieve outstanding quality and the highest possible standards meant the hotel tower had to convey a sense of luxury, and deliver an unparalleled civic and guest experience. Faced with these challenges, the developer’s management team, Qingdao Guoxin Haitian, turned to RWDI for exacting analyses and original thinking to ensure a viable design, occupant safety and comfort, and secure approval from the authorities.
Our Approach
Working from our analyses, we knew a revolutionary response was needed to minimize wind-induced vibrations on the tower, and meet requirements set by China and the international building codes. We teamed with the project’s structural engineers, CCDI and studied the possibilities for tuned sloshing dampers (TSDs) with a unique twist. Sparked by necessity and imagination, we collectively designed the world’s first irregular shaped tuned sloshing dampers, which double as fire suppression tanks.
A TSD tank is partially filled with fluid and located near the top of a structure. With the right TSD tank dimensions and fluid depth, the natural frequency of the sloshing motion can be “tuned” to a natural frequency of the structure. When the structure experiences vibrational energy from winds, this energy is transferred to the TSD tank fluid, where it is dissipated by damping mechanisms inside the tank.
After solving this particularly challenging issue, the pioneering design of the irregularly shaped TSD tanks had to be studied in detail to ascertain their performance.
- Using an in-house analysis tool, we modeled the behavior of the dampers in typhoon and earthquake conditions.
- We then conducted scale-model testing of a representative tank on a shake table, in order to verify the behavior of the sloshing fluid and validate predictions.
- We staged a Motion Simulation Workshop to help the development team understand the effects of the dampers. This allowed the team to experience firsthand the change in motion before and after installation of the dampers inside RWDI’s motion simulator.
Our comprehensive wind engineering studies also benefited the Qingdao Guoxin Haitian Project through potential cost savings and streamlined approvals. We provided Wind Tunnel Testing and a Cladding Wind Pressure Study to help optimize the project’s structural design. Our Wind-Induced Structural Responses Study further enhanced structural design and promoted occupant comfort. To make the complex inviting – even before visitors enter the buildings – we provided a Pedestrian Wind Study that simulated wind speed and direction at street level and tower entrances. The design team and wind engineering experts agreed with the results of these studies and our work smoothly passed China’s stringent EPR (expert panel review).
The Outcome
The Qingdao Haitian Hotel sets a new bar in tower design. Our collective ingenuity and ability to customize applications gave rise to a state-of-the-art TSD solution that achieved numerous goals simultaneously. The dual-purpose tanks dampen vibrations and act as fire suppression, which saves costs and maximizes leasable space. In addition, their irregular shape helped avoid the need to redesign the building’s layout. Our ability to successfully provide wind engineering analyses and results that pass EPR in China and gain authorities’ approvals helped make the project viable and kept it moving forward.
By working closely with the design team and maintaining in-depth project participation, we helped the developers achieve their vision, elevated the building quality, and devised innovations to make the Qingdao Haitian project a truly iconic development in China and the world.