How by choosing an appropriate system the cost of construction for a high-rise building can be reduced ?

 By choossing an appropriate system the cost of construction can be reduced e.g.the Shanghai Word Financial Centre (492m height ) is an extraordinary building making use of composite , steel and concrete mega-structure , the structural system is organized to respond to the beauty of the architecture while meeting extraordinary engineering challenged.In order to decrease the weight of the building, the majority of that decrease had to be found in a reduction of the thickness of the concrete shear walls of the services core. This reduction could be achieved only by decreasing the wind- and earthquake-induced lateral forces resisted by those walls. That decrease could be found only by increasing the stiffness of the lateral force resisting system of the perimeter wall.

Accordingly, abandoning the Developer’s design for the perimeter framing (that of a Vierendeel moment-resisting space frame), LERA resurrected its1995 design: a diagonal-braced frame with added outrigger trusses. This change enabled a decrease in the thickness of the services core shear walls, as well as a decrease in the weight of structural steel in the perimeter walls. Further, by making use of outrigger trusses coupled to the columns of the mega-structure, an additional reduction was realized.

These conceptual changes made possible the ability to design an efficient and economical structural system while still responding to the constraints of the existing piling.