The Use of Magnification Factor Formula in Partial Capacity Design Method for Fully Ductile Moment Resisting Frames

Abstract

The concept of Partial Capacity Design (PCD) offers a new attractive alternative in the seismic design especially for fully ductile moment resisting frame. Different from conventional Capacity Design which attempt to maintain the condition of “strong column weak beam”, PCD allows the interior columns become plastic while the exterior columns are kept being elastic during severe earthquake. In order to maintain the elastic condition, columns are designed to sustain larger seismic load by multiplying the nominal seismic load with a Magnification Factor. The latest study on PCD recommends the use of an empirical formula to define the value of Magnification Factor. The objective of this study is to check the validity of the formula. Eight symmetrical fully ductile concrete moment resisting frames consist of 6- and 10-story, 4- and 6-span in zone 2 and 6, are designed in accordance with the Indonesian Earthquake Code (SNI 03-1726-2002) using the PCD method and formulation. The seismic performances of these buildings are evaluated using three dimensional static nonlinear pushover and dynamic nonlinear time history analysis. The results show that the empirical formula of Magnification Factor applied well. Furthermore all structure has good seismic performance and meets the failure mechanism as expected.