Irregularity Effects of Masonry Infills on Nonlinear Seismic Behaviour of RC Buildings

Table 1

Calibrated values of parameters of masonry infill panels.

Elastic modulus Emo (kPa)	1158000
Compressive strength fn (kN)	680
Tensile strength (kN)	0.5
Strain at max stress εm	0.004
Closing strain εcl	0.04
Unloading stiffness factor γun	1.6
Reloading strain factor αre	0.48
Strain inflection factor αch	0.90
Complete unloading strain factor βa	0.99
Stress inflection factor βch	1.4
Zero-stress stiffness factor γplu	0.7
Reloading stiffness factor γplr	1.7
Plastic unloading stiffness factor ex1	3.2
Repeated cycle strain factor ex2	1.7
Shear fraction γs (kN)	140
Friction coefficient µ	0.9
Bond shear strength τo (kN)	250
Reduction shear factor αs	1.8