This kind of vibration would be unacceptable to people occupying a building or driving across a bridge. The thicker a beam, the less likely it is to bend. Thick beams are used in structures that experience live and dynamic loads. The thick beam absorbed the vibrations caused by the dynamic load and prevented the structure from bending and galloping wildly out of control. When wind blows on a structure, it is called wind load.
Wind loads push horizontally on a structure.
The structure collapsed because it couldn't withstand the strong gusts of wind. Diagonal braces, usually made of steel, are used to strengthen and stabilize all kinds of structures. Cross-bracing is an excellent way to stiffen a structure experiencing wind load. When the wind blows, the diagonal brace squeezes together and prevents the structure from flopping over. When a structure expands or shrinks with the temperature,it is experiencing thermal load.