Viana do Castelo, Portugal
The building of the Municipal Library of Viana do Castelo has two stories divided structurally into two distinct zones. One (zone 1) continuously supported at floor 0 level in the foundation, and another (Zone 2) which is supported on two L-shaped columns and in the zone 1, freeing the lower space as was intended by the architecture.
The structural scheme adopted consists of a beam lattice grid at the coverage level supported zone 1 of the building and in two crossed metal which under the 1 floor becomes two L´s that for architectural reasons have one of the flaps placed in the less inconvenient, yielding tractions on the outer side of this flap. This metal grid suspends by struts the floor of the library that consists of a mixed structure of steel beams with reinforced concrete blades on the upper and lower face (apparent concrete).
Given that this whole area should have the minimum possible deformations, we decided to prestress with Dywidag rods the traction area of the cross shape support and with post-tension the mixed slabs of the hanging deck.
It should be noted that the apparent concrete is white and that the special characteristics of the work, drawing stereotomy, presence of metal structure, proximity to the sea, thick concrete sometimes thin sometimes thick (0.12 , 0.30 , 0.42 , 0.54) demanded great accuracy in the study of its composition, and the study of the formwork. The collaboration of the contractor including the direction and site preparation, enable the successful completion, with the necessary quality, designed the building.