Lifting of the provisional staying towers of the Almonte Viaduct

Abstract

For the lifting of the provisional staying towers of the Almonte’s viaduct, a 4-bar mechanism has been used, more commonly known as a slider-crank mechanism. It allows, with the arrangement of two heavy lifting jacks which activate the mechanism, to move the tower from an horizontal position on the deck to vertical position above the pier. The basis of this mechanism is known since antiquity and basically consists of a slipper that by means of an external action is moving on a rail and to which is attached a biarticulated rod at its two ends. This rod rotates and makes the tower rise to the vertical position.