QI// A three span one way slab as shown in Fig. 1 is supported on 300 mm wide beams with clear spacing of beams is 4.5m, the slab carries a service dead load of 0.5 kN/m² in addition to self-weight and a service live load of 6 kN/m². Use fe = 28 MPa and fy = 420 MPa 1-Estimate the slab thickness using limitation of ACI-318M. 2- Use the ACI-318M moment coefficients to determine the design moments at critical sections of the slab. Fig.1 300 4.5m 300 4.5m 300 300 4.5m

Q1 For the composite beam shown in fig. 1. Draw bending stress distribution .if E₁= 20 000 MPa., E22000 MPa. E1 20 000 MPa 20 MM- MATERIAL 1 E2 2000 MPa 10 kN A -4 M B 50 MM MATERIAL 2 100 MM -2 M -200 MM-

A simply supported post-tension beam as shown in Figure (1), span length is 14m, carries a uniformly distributed service live load of 10 kN/m. Find the value and location of initial pre-stress force (Pi), so that the mid span stresses in concrete at top fiber is zero at initial stage and zero stress at bottom fiber in service stage. Total losses in pre-stressed force are 15%. 100 200 100 750 100 400 Typical Cross section. Figure (1)

A rectangular R.C beam of detail shown in Fig. subjected to bending moment of (150 kN.m), n=9, f'c = 28 Mpa, fy = 413Mpa, use the working stresses method (Cracked State) to find: 1- Maximum compression stresses in concrete. 2- Maximum tensile stresses in steel reinforcement. 4025mm 250 mm 500mm 70 mm