Saturday, October 9, 2010

Top Down Construction


The top-down method of construction enables a high-rise superstructure and its sub-basement to be built simultaneously. Perimeter foundation walls are constructed using the concrete diaphragm or secant wall methods. Load-bearing elements or drilled shafts are installed and the building columns brought up to grade level. Ground level and first basement slabs are poured, with access holes left to allow excavation beneath. As each subsequent subgrade level is completed, the floors act as lateral bracing for the perimeter wall system. Above grade construction can proceed while the subgrade work is ongoing since the building’s structural support is already in place.

Take from http://www.casefoundation.com/services/topdownconstruction.aspx

Sekilas mengenai top down construction methode,
metode ini didasari dari dua kepentingan :
1. menekan biaya pembuatan retaining wall pada multistore basement struktur (struktur basemen betingkat banyak) yang biasanya menggunakan soil nailing maupun strouting.
2. menekan waktu yang lama pada saat menggunakan metode konstruksi bottom up. dimana waktu terbanyak biasanya dipakai untuk pembuatan retaining wall dan struktur basemen. baru setelah selesai dilanjutkan dengan upper structurenya.