Just like tree branches rustling in the breeze, skyscrapers do sway in the wind. Their steel construction allows for normal swaying without endangering the building's structural integrity nor disturbing the occupants’ comfort inside… and they have a secret weapon: the TMD.
The TMD (Tuned Mass Damper) is a mass, mounted to a specific location in a high rise, so as to reduce the amplitude of vibration to an acceptable level whenever a strong lateral force, such as high winds, hit. It ‘damps’ the low-frequency vibrations and reduce their amplitudes especially on the upper floors. TMD’s are frequently used in power transmission, automobiles and buildings.
Usually hidden in the high-rise structure of the building, the TMD is sometimes visible. The most famous one is the one at Taipei 101 (Taiwan). Between the 88th and 92nd floors, an impressive gold-coloured, 730-ton orb swings gently back and forth, balancing the tower against the forces of the wind, ensuring the comfort of its occupants and preventing structural failure.
No gold-coloured TMD on the 250-metre high Mohammed VI Tower, however, but an impressive 160 tons TMD, made of several steel plates. The last few weeks, the plates have been progressively brought up to the last few storeys of the tower – a very delicate exercise as you can see on the pictures below.
Our BESIX-TGCC teams just finished the installation of this impressive device.
Congratulations to our colleagues for reaching this major milestone!
