PROBLEMS\ Note: For all problems use load factors from ACI Code Section 5.3.1 and strength reduction factors from ACI Code Tables 21.2.1 and 21.2.2.\ 4-1 Figure P4-1 shows a simply supported beam and the cross section at midspan. The beam supports a uniform dead load consisting of its own weight plus

1.5kip(s)/(f)t

and a uniform live load of

1.2kip(s)/()

ft

. The concrete strength is

4500\\\\psi

, and the yield strength of the reinforcement is

60,000\\\\psi

. The concrete is normal-weight concrete. For the midspan section shown in Fig. P4-1b, compute

\\\\phi M_(n)

and show that it exceeds

M_(u)

.\

w_(D)=1.5kip(s)/(f)t

plus weight of beam\ (a)

PROBLEMS Note: For all problems use load factors from ACI Code Section 5.3.1 and strength reduction factors from ACI Code Tables 21.2.1 and 21.2.2. 4-1 Figure P4-1 shows a simply supported beam and the cross section at midspan. The beam supports a uniform dead load consisting of its own weight plus 1.5kips/ft and a uniform live load of 1.2kips/ ft. The concrete strength is 4500psi, and the yield strength of the reinforcement is 60,000psi. The concrete is normal-weight concrete. For the midspan section shown in Fig. P4-1b, compute Mn and show that it exceeds Mu. wD=1.5kips/ftplusweightofbeamw1=1.2kips/ft (a)