EVALUATION OF FNP FOR RC FRAME WITH BRICK INFILL

Amitkumar D J, G.N. Bhadri, S.S.Dyavanal

Abstract: The RC multistoryedframe buildings are commonly built with brick masonry as infill walls.Window and entryway openings are unavoidable piece of the infill dividers. The vicinity of openings in infill dividers fundamentally lessens the parallel quality and solidness of RC casings. The fundamental natural period (FNP) of the building with infill panels depend on strength and stiffness of these infill. The strength and stiffness effect of the infill walls are not considered in any of the seismic codes across the world for calculating FNP. An attempt is made in the present paper to evaluate a new empirical formula by method of least squares (MLS), considering the stiffness of the infill walls and number of bays and storeys. The analysis is carried using SAP v14.2 for gravity and seismic loading. Gravity analysis is carried out as per IS 456: 2000 code provisions. Seismic analysis is carried out as per IS 1893 (Part 1): 2002 procedures for multistoryed ordinary moment resisting frame (OMRF) buildings. All the models are constructed in seismic zone IV.The FNP results by MLS are compared with periods obtained from empirical formulae prescribed in seismic codes across the world.The authors conclude that, FNPs obtained by MLS are accurate than the FNPs calculated from the empirical formulae given in seismic codes considered in the paper.

Keywords: Fundamental Natural Period, Infill Frame, Method of Least Square, OMRF, Seismic Code

DOI: https://doi.org/10.15623/ijret.2015.0411055