Design parameters effects on the required steel areas of two-way slabs

Abstract EN

The present research shows clearly the effects of yield strength of steel, compressive strength of concrete, thickness of slab and the bar diameter used on the areas (As) of steel required in edge-supported two-way slabs (short and long direction).

The analysis was done by computer program constructed by author utilizing the facility of coefficient method to analysis the two-way slabs.

A survey analysis and design had been done for many cases of study considering the shear forces effect and deflection limits according to the (ACI 318M-2008) requirements.

The results of analysis and design are briefly discussed.

Among conclusions the results show if (fc') increases from 15MPa to 35MPa the (As) will be decreased about (13 %) if (Mu2/d =3.5 kN/m ) and for any values of other variables, also it is not economical to use high strength of concrete when the term (Mu2/d) between (0.5-1 kN / mm) because the gain in areas of reinforcement will be very small.

The study proved that when the thickness (t) increases (50 %), the (As) decreases (28 % to 32 % according to the parameter Mu1/fc ), while ; if the thickness of slab increases (100 %), the (As) will decrease (62 % to 64 %).