Video of roof-top pool sloshing during an earthquake in Bangkok
Well this is something new. The news today is full of reports of the severe damage in Myanmar where a 7.7 magnitude earthquake destroyed many buildings including some brand-new construction projects.
Over a thousand miles away, but along the same geological fault-line, Bangkok was also violently shaken. Far less damage occurred because of better building codes, but some novel effects of an earthquake on tall buildings were dramatically demonstrated. Bangkok’s newest skyscrapers often have large swimming pools on the upper floors or roofs, purposely included in the design to act as “mass-dampers.” The reaction of the large volume of water resists the building’s swaying during earthquakes by absorbing energy and countering some of the shaking motion.
Free to move, the large masses of water in such pools are accelerated into waves by the earthquake's shaking force thus absorbing energy and reducing the stress on the building’s structure. Larger waves do spill over the pool’s edge, as expected by the design, resulting in spectacular cascades of water down the sides of several of Bangkok’s newest high-rises during an earthquake.
The short video below dramatically illustrates these phenomenon …. as seen from a pool security camera. The spilled water is heading down 30 stories to the street below
