Gaudí planned inclined branching columns in the shape of a tree for the church.
From a long, meticulous empirical study of models of inverted weights with chains or strings and graphic calculations, he managed to determine the inclination of the load-bearing elements (columns-trees) in order to optimise the structural behaviour by transferring the loads to the central nucleus. In that way he makes the compression elements work and reduces the flexed elements to the minimum. He also manages to bring down the main loads along the interior pillars of the nave and not along the perimeter of the floor or the exterior elements.
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BEYOND THE GOTHIC
THE TREE STRUCTURE
THE CALCULATIONS OF LA SAGRADA FAMÍLIA