Name: 1 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED. CE311 Fall 2017 Exam 3 11/16/2017. ASD Load Combinations: LRFD Load Combinations:

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1 CE 311 Celebration of Knowledge points November 16, 2017, 7pm to 9:30pm YOU MUST CITE ANY AISC DESIGN AIDS USED You are allowed to have the AISC manual, and a calculator. Given Formulae: Live Load Reduction Factor: Name: ASD Load Combinations: LRFD Load Combinations: THEORETICAL K-VALUES. Table C-A-7.1 Approximate Values of Effective Length ABBREVIATIONS psf pounds per square foot plf pounds per linear foot k kip (kilo-pound) DOI Degree of Indeterminacy 1 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

2 Bonus Questions 1. (0.1 points) The Battle of Midway is considered the turning point in the US war against Japan in World War Two s Pacific theater. In what year did this battle take place? 2. (0.1 points) What right was guaranteed by the 19 th Amendment to the US Constitution? 3. (0.1 points) Who is the only college football player to have been awarded the Heisman Trophy twice? 4. (0.1 points) On what date did Mao Zedong declare the formation of The People s Republic of China? 5. (0.1 points) TRUE or FALSE. Lafayette College shared the College Football National Championship with Alabama in (1 point) Team A vs Team B. Las Vegas lists the game as Team A (+3.5), with an over-under of 48.5, so you decide to bet $1000 on Team A, while putting $500 on the over. Team B beats Team A by a score of 24 to 21. How much money did you win or lose? Engineering Bonus Question (4 points): Determine the net area of the C6x13 channel, considering fracture path abcd, only. Given: ¾ bolts in standard holes. Engineering Bonus Question (4 points): Determine the plastic moment capacity M p for a 1 diameter steel rod that has F y = 50 ksi. 2 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

3 1. (5 points). What is the ASD allowable strong-axis bending moment for an A992 (F y =50 ksi) W21x55 shape that has its compression flange continuously braced? Mn/ = kip-ft 2. (5 points). What is the ASD allowable strong-axis bending moment for an A36 (F y =36 ksi) W21x55 shape that has its compression flange continuously braced? Mn/ = kip-ft 3. (2 points) TRUE or FALSE. If a wide-flange shape is known to be compact for F y =50 ksi, then it is definitely compact for F y =70 ksi. 4. (4 points). A W18x76 is made from F y =100ksi steel, while its compression flange is continuously braced, in strong-axis bending. Circle the correct answer a. M n = M p b. M n = M r c. M n < M r d. M p > M n > M r e. I m hungry 5. (2 points). (Circle the answer). Assuming each has the same cross-sectional area (and, therefore, the same weight and cost), which shape (A or B) is better suited for the application, shown. Cross Section (A) Cross Section (B) Long P Long 3 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

4 6. (15 points) Select the lightest A992 Wide-Flange shape for a typical interior fill beam, for the floor plan shown, assuring adequacy with respect to ASD specifications. Given: Beams support a 5 thick normal weight concrete (unit weight = 150 lb/ft 3 ) slab, which continuously braces the top flanges of the beams, laterally. Loads to Consider: Slab Weight, Beam Self-Weight, and a live load of 70 psf (use 70psf live load. The live load reduction factor has already been applied). Live Load Deflection not to exceed L/360 Notes: All connections are simple, non-moment-resisting. 36, typ 32, typ FLOOR PLAN s Selection: M: kip-ft M n / = kip-ft V: kips V n / = kips LL = inches 4 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

5 7. (15 points) Select the lightest A992 W shape that is adequate for the application, shown. Ignore self-weight. Do not consider deflection or shear kips kips s Selection: M: kip-ft M n / = kip-ft 5 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

6 8. (20 points). An A36 S8 x 18.4 beam is used as a crane rail, spanning 15 feet. Determine if this beam can safely lift 6 kips, at midspan, using ASD specifications ( = 1.67). Given: Laterally and vertically supported at the ends, only 15-foot span L r = inches Ignore Self-Weight A36 S8 x 18.4 Crane Rail Cross Section S 8 x kips FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED

7 9. (5 points). Determine the ASD design strength R n / for the welded connection. The base metals are A36. The E60 fillet welds are 3/8. The gusset is ¼ thick. The angles are 2L5x5x½ R n / Cross-Section 2L5x5x½ ¼ Gusset 3/8 E60 Welds 3/8 5 3/8 10 Rn/ = kips 10. (8 points). Determine the plastic moment capacity M p for a x solid, rectangular steel (F y =50 ksi) shape, bent about the axis, shown. Note that = Axis of Bending 7 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED Mp = kip-in.

8 11. (19 points) Determine the AISC ASD PM Interaction ratio. Given: A992 W16x36 (F y = 50 ksi) Concrete slab braces the top flange Distributed load of 1 kip/ft already includes the beam self-weight Axial force = 75 kips Assume second-order effects are negligible w = 1 kip/ft 75 kips Concrete Slab W16x36 A kips 30 Interaction ratio = 8 FOR ANY AISC DESIGN AIDS: YOU MUST SPECIFY THE TABLE USED