In concrete construction the effect of changing storey height againnst to irregular stiffnes in neighbour storey

Key words: Poor floor irregularity, floor height ratio, Mod combination method. In this study, 5 floored symmetrical building has been solved in different floor heights. By the assistance of ideCAD of a total of 68 different construction models; the 3 dimensional dynamic analyses have been made by Mod combination method. For the purpose of evaluation of the rigidity irregularity behavior of the constructions between the floors; the Poor floor irregularity was submitted as reports and by at the end of the study by shortly summarizing the results in hand the evaluation of regulation related with the buildings to be constructed in earth quake zones (D.B.Y.B.H.Y 2007) has been made. As a result of the study: As the values of the biggest floor height ratio found at the graund flor of the structure with the biggest floor height ratio of hi= 2.00 m that is obtained according to the regulation related with the buildings to be constructed in disaster areas ( A.B.Y.Y.H.Y.97) is 1.75 floors: in other words as it is being found as: 1.75 X 2= 3.50 m; the same construction will be 4.65 according to the regulation related with the constructions to be built in earthquake zones ( D.B.Y.B.H.Y.2007); in other words: it has been found as : 4.50 X 2= 9.00 m. The biggest floor height ratio?s ratio for the same construction between the two regulations has been determined as: 4.50 / 1.75= 2.57 By starting from these values, the thing that is to be done; to review the rigidity irregularity between the floors of the regulation related with the constructions to be made in earth quake zones ( D.B.Y.B.H.Y.2007) and lower the nki< 2 value or to decrease the floor height impacts in the formula or remove them from the formula.