Day 6 – Chile Earthquake 2010 – University Bldgs
Bldg 3-13
University Andres Bello (36⁰ 46′ 46″, 73⁰ 04′ 33″)
Four-story private university with one older wing and a newer wing under construction. On the picture of the model, it represents one half of the main wing and one half of the longest of three fingers. The rest of wings are yet to be built. The main entry has a large cantilevered overhang supported by concrete braces. There is a lot of mass at the cantilevers with a 3 story concrete wall at the tip of the cantilever. The structural system of the building is a concrete moment frame in both directions in the newer wing and concrete shear walls in the older wing. The concrete moment frame portion had a lot of exterior glass damage. The entire building façade is a storefront system. Unlike the practice in CA, the glass does not sit inside a mullion shoe but is epoxy glued to the face of the storefront so that you don’t see the mullions from the outside at all. Bad idea as evidenced by the damage to the glass. The other concentration of damage was at the concrete stair that is approximately in the middle of the new portion. Our conclusion was that the stair acted as a huge brace and attracted most of the load and the damage. The building was life safe, the Chilean code requires a 1.2 importance factor for university buildings. Another interesting observation was the cantilever end was sloping down about 5%, the contractor told us that they built it 2″ up.
Bldg 3-14
University de Concepcion (36⁰ 49′ 49″, 73⁰ 02′ 12″)
This is a beautiful large university in downtown Concepcion. We saw a 3-story steel braced frame building (chevron), very regular about 50 ft x 175 ft in plan with 4 braced frames in each direction. The building houses the Civil and Systems Engg. Departments. The Columns are 12″ tubes, beams are all 21″ channels or a combination of channels. The building did not have any damage or signs of yielding in the frames or connections. Just next to it was a similar building a few bays longer that was completely burnt except for the structural frame. We were told that this was a chemistry building where the contents caught fire after the earthquake.
