Structural Description
FMC Tower at Cira Center South includes three parts: 575,000 SF of office space, 235,000 SF of luxury residential space, and 10,000 SF of retail. It includes Cira Green, a one-acre park atop the existing parking garage, connected by a skybridge to FMC Tower
|
System Selection
The construction of this project began in 2014, and it might be finish in Summer 2017. The structural system for the residential part are all concrete, and the structural system for the office part is both concrete and steel. The figure on left shows the concrete and steel frame of the building. There are several reasons for choosing that typical system. First, because of the wind loads, rigid core (concrete) lateral forces taken by shear walls. Secondly, the damper on the top floor reduces magnitude of lateral motion of top of tower. At the same time, the steel on the outside of the building takes up less space. The technique of using concrete frame structure is well-known nowadays. It has been utilized for many years. The whole system consists of concrete beams, columns, and girders that transfer the loads into the concretes. As described above, there are many advantages to a reinforced concrete frame. However, there are also some disadvantages. The biggest the concern would be the self-weight of the reinforced concrete. Since there are total three parts, especially a 50-story building, if all the structure is concrete frame, it will produce tremendous self-weights, I think that's one of the biggest reason why construction company chose to use both concrete and steel frame for office space instead of only concrete. They wanted to reduce the use of concrete. |
Structural Improvement
Philadelphia is known to be a windy city. It will experience several severe windy days in a year. Although the concrete material has a very good performance in the compression, when it comes to tension or shear, it is not as efficient, especially it's a 50-story high building. I think a more aerodynamic structure should be helpful the reduce the wind load to the building.
Philadelphia is known to be a windy city. It will experience several severe windy days in a year. Although the concrete material has a very good performance in the compression, when it comes to tension or shear, it is not as efficient, especially it's a 50-story high building. I think a more aerodynamic structure should be helpful the reduce the wind load to the building.
Load Patterns
Numerical Parameters