Vancouver, BC

The Charleson

The Charleson is 44-story residential building with an irregular plan. Due to vortex shedding and open wind exposure of the building, the building was assessed to have relatively high acceleration. To mitigate the building vibration, a single large Tuned Liquid Sloshing Damper (TLSD) was designed. However, due to the fact that the excess of acceleration is not high and usually as-built building frequency is expected to be better than the theoretical value, supplemental damper design was postponed until building structure was nearly completion. This new procedure allowed very efficient damper design based on actual building frequencies and corresponding real building responses.

Vancouver, BC
In order to meet the purpose described above, the new design procedure required very flexible damper system which does not required prefabrication of permanent structures such as concrete tanks or supporting structures. Besides, since the required level of supplemental damping was determined after building topping-off, the damping system has to be adaptable to the available space at the time of completion of the tower. In order to satisfy these conditions, Gradient Wind Engineering invented Modular Damper, and designed, tested and successfully installed in The Charleson as the first time of the same kind not only in North America, but also in the world. Whereas conventional Tuned Liquid Sloshing Damper (TLSD) requires a large space with concrete walls and mechanical systems for water supply and drainage and its space should be allocated during the early design stage, Modular Damper can be divided in to multiple small units and can be distributed into available spaces, which allows flexible damper design. The benefits of MTLSD can be summarized follows: i) it does not require a permanent structure, such as concrete tanks; ii) the necessity/number of tanks can be determined after the as-built building properties are known from field monitoring; iii) since the modular damper units are light and convenient for delivery, construction cranes are not required to stay for the installation of the damper; iv) the tanks are virtually leak-free and easily replaceable, as necessary. The modular dampers will help structural engineers and building developers minimize the necessary building space for the damper, and also reduce construction costs by introducing a versatile and adaptive damping solution for tall buildings.