Housing and Commerce Building
PECS was responsible for the structural and foundation projects and for some specialties of the residential and commercial building located in Santa Cruz, Madeira.
In addition to the development of the projects, he was also responsible for their coordination and for monitoring the respective administrative licenses.
It is a building composed of eight floors, two buried (floors –3 and -2), a semi-buried floor (floor -1) and the remaining five in elevation (floors 0 to 4). The underground floors are intended for parking, floors 0 and 1 for commerce and the rest for housing. The building has an implantation area of 1300 m2, developing in a U-shape around a central courtyard from the ground floor.
The proposed structural solution involves the use of massive fungiform slabs of 0.20 m thick, with capitals 0.40 m thick on floors -2 to 2, and massive fungiform slabs of 0.30 m thick on floors 3, 4 and running machine. These slabs work supported directly on pillars, beams and walls, which transmit the loads to the foundations.
Given the high loads coming from the superstructure and the weak geomechanical characteristics of the top layer of the land, the foundation of the building is foreseen through indirect micro-pile foundations injected at high pressure with diameters of 180 and 205 mm. The option for a solution of micropiles instead of reinforced concrete piles is due to the difficulties in the execution of the latter in a land made up of disaggregated stone blocks with reasonable dimensions. The micropiles are made by inserting a head tube with valves along the entire sealing length into a previously drilled hole. The injection technology to be used will be of the IGU type (single global injection), in which the grout is injected at once through a tube with a simple plug placed on the head of the tubular profile.
Due to the existence of a water table (about 3.75 m of maximum water height in relation to the bottom slab), at the level of the floor -3, it was decided to use a 0.15 m thick reinforced rig ( A welded mesh AQ50) is placed, a layer of gravel 0.35m thick, applied over a foundation slab 0.35m thick. The gravel layer is used to drain any residual water to the pumping station.
Once the peripheral retaining walls of the building are already completed up to a level higher than that planned for the building's implantation, it is necessary to deepen them. This deepening consists of the demolition of the shoes of the existing walls, excavation to the project level, execution of new micropiles and concreting of the rest of the wall and a new support shoe.
As floor –3 does not occupy the entire area of the building, it was also necessary to create a reinforced concrete wall to create a gap between floor –3 and floor –2. After an inspection of the site, it was possible to observe that the land in this area was somewhat unstable. In this way, it was decided to make a micropile curtain with a spacing of 1.00 m that serve simultaneously as a foundation and provisional containment during the excavation.
The entrance pergola, in wood (glued laminated type), is the result of the work developed between Architecture and Structure. This structure supports at the level of floor 2 and floor 1, through metal tubes ROR 139.7x6. The wooden elements are joined using ROR 193.7x8 metal tubes.