Effect of pre-tensioned loads to vibration at the ladder tip in raising and lowering processes on a turntable ladder

A turntable ladder is an indispensable vehicle in fire and rescue work. Vibration on the top of the ladder is considerable when the ladder set is maximally extended. It induces the discomfort and unsafety for beings in the rescue cage. Aiming at the reduction of the vibration, in this study, one additional steel wire rope is assumedly added into each handrail of the ladder set. The steel wire ropes are suggested to be pre-tensioned before the turntable ladder works. This study is based on an available ladder set structure which includes three ladder sections with different area moments of inertia. Additionally, a ladder structure model is established as a multibody system dynamic model. The changes of kinetic parameters in the raising and lowering processes of the ladder set are investigated. The obtained results can be the fundamentals for modeling, experiments and applications of turntable ladders.