Dr. M.E. Haque, PE 1
A Simply Supported Reinforced Concrete Beam -
Three stages before collapse:1. Un-cracked Concrete stage2. Cracked Concrete (tension zone) - Elastic Stage3. Cracked Concrete (tension zone) - Ultimate Strength Stage
Typical Stress-Strain Curves for Concrete and Reinforcing Steel
1. Un-cracked Concrete stage
1. Un-cracked Concrete stage
1. Un-cracked Concrete Stage
fcft = fcStress-Strain Diagram for Concreteft < frM < Mcr fc = ft
2. Cracked Concrete (Tension Zone) - Elastic Stage
ft > frM > Mcr fc = 0.45fc'fs =0.5 fy
3. Cracked Concrete (Tension Zone) - Ultimate Strength Stage
ft > >frM > >Mcr fs = fyfc = entire stress block until compression failure