ATD Plaza (Menara Thamrin)

Location

Jakarta

Client

PT Aditya – TOA

 

In the case of ATD Plaza, Wiratman simplified the 3-dimensional structure into its 2-dimensional equivalent, especially on its calculation against earthquakes. Wiratman calculated it as a 2-dimensional structure, as a plane frame and not a space frame, thus making it simpler.

The calculation of earthquake impacts was not only in the plastic domain, but also in the elastoplastic domain. ln the elastoplastic domain, to endure strong earthquakes, the structure needed to be designed to have a ductile behavior, to give the structure the ability to deviate far to its side without collapsing.

The simplification of a structure's behavior in earthquakes was considered a necessity at the time. Earthquakes must be carefully considered in a structure's design and the much simpler calculation based on the 2-dimensional equivalent model helped structural engineers to easily predict the behavior of a high-rise building should an earthquake hit.

The ATD Plaza, being a typical Japanese box-shaped building, is structurally unimpressive. The building is simple; there are no long spans, and no irregular forms either. The impressive aspect is the applied precast concrete that Wiratman applied in many of its structural elements.

A precast concrete system was applied to the stairs, cladding and the hollow core slab. The columns and beams of the building, however, were not precast concrete. At a time when many buildings still applied on site concreting, ATD plaza was one of the first buildings using prestressed precast concrete.