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**Problems:
**

**1. **Determine the ultimate moment capacity, *fM*n, of a beam with dimensions b = 14 in.,
*d*effective= 17.5 in., and h = 20 in., and that has three No. 10 bars (3.81 in.

2 ) of tension-

reinforcing steel. *F*y = 60 ksi, and *f’c = *4 ksi.
Answer: *fM*n = 258.9 k-ft

**2. **For the beam of Problem 1 which is simply supported and 32 ft long, and where the loads
are dead load = 320 lb/ft (not including self weight) and live load = 185 lb/ft, determine if

the beam is adequate in bending. = 150 lb/ft 3 .

Answer: yes (*Mu
* = 131.8 k-ft)

**3. **For the beam of Problem 1, check whether the amount of tension steel is within the limits

for ductile beam behavior. (*Refer to the table for maximum ** in Note Set 10.1)**Partial** Answer:* yes (*As*-max

= 4.43 in.2)

**4. **For the beam of Problem 1 and 2, calculate the shear capacity, *vV*c,
and determine if the

beam will required stirrups.

*Partial** Answer:* yes (*Vmax *>
2

*cvV*
= 11.6 k)

**5. **A reinforced concrete column in a rigid frame has a design compression load of
Pu = 170 kips, and a design moment of Mu = 34 k-ft. With the interaction diagram

provided on the next page, determine the amount of reinforcement (number and size of

bars) required for a 10 in. square column.*Partial** Answer:* more than 4-#7.

**6. **A two story, three bay portal frame has lateral loads from wind at each story as shown. All
columns are W12 x 40’s while all beams are W 18 x 55’s. Using a computer-based structural

analysis program, determine the shear, bending moment and axial load in each member (V, M

& P). Identify the column and beam with the critical design values. *Submit the model file
*

*(.mfd) on E-learning, and provide a print of the diagrams.**Partial Answers:* Vmax (2

nd windward column, 1st story) = 31.35 kN

Vmax (1 st windward beam, 1st story) = 11.10 kN

Pmax (1 st windward column, 1st story) = 14.89 kN

Pmax (1 st windward beam, 1st story) = 54.19 kN

Mmax (2 nd windward column, 1st story) = 75.76 kN-m

Mmax (1 st windward beam, 1st story) = 60.43 kN-m

75 kN

40 kN

10 m 10 m 10 m

4. 5

m

4. 5

m

W18x55

W 1

2x 40

2

**7. **Is the ultimate tensile capacity of 2-#6 grade 40 reinforcing bars greater than that of 1-#8
grade 60 bar?*Partial** Answer*: 2-#6 *T* = 35.2 kips, 1-#8 *T* = 47.4 kips