SHEAR LAG

2. In 2 words, what is the reason for calculation of a reduction coefficient, U, for effective net area, Ae? SHEAR LAG

3. Name the three strength limit states for tension members. Yield of the gross cross section, net area fracture, and block shear

4. What is s2/4g and how is it used? It is a ‘length correction’ for calculation of net area when considering net area fracture paths for staggered bolts.

5. For this W18x40 subject to tension, with bolted splice plates at the top and bottom flanges, what would you use for connection eccentricity, x? WT9x20x=2.29”AISC Table 1-8 [1-58] 2.29” USE AISC MANUAL

6. Which block shear path would you NOT check and why not? 1 2 3 #1, since the middle bolt would also have to be sheared

7. Name the serviceability limit state for tension members based on ease of handling and prevention of excessive sagging or vibration. L / r less than or equal to 300

8. What is the general rule of thumb that determines whether or not a hole can be punched? dhole greater than tplate(often quickly check dbolt≥ tplate)

9. What is the definition of ‘gage’ length? Distance between bolts perpendicular to the direction of loading

10. What is the f factor associated with fracture, what is the f factor associated with yield, and why is one lower than the other? 0.75, 0.9, lower resistance factor results in a higher margin of safety for brittle limit state of fracture

11. If Tu=120 kips, and the service load, T, is 25% dead load and 75% live load, what is the value of T? Tu=120 kips=1.2D+1.6LL=3D120 kips = 1.2D+1.6(3D)=6DD=20 kipsT = D + L = D + 3D = 80 kips

12. Bolted connecting elements (e.g., splice plates) are typically ‘short’ with limited inelastic deformation. Therefore, we apply this ‘rule’ as an additional factor of safety: The 85% ruleAe = An ≤ 0.85 Ag AISC J4.1

13. In this equation for capacity of a tension rod or bolts in tension, one 0.75 is the resistance factor; what is the purpose of the other 0.75? The other 0.75 provides a way to account for the reduced cross-sectional area of the threaded portion.

14. Why does the equation for bearing capacity of a bolt include Fu of the plate or connected part? Derivation of the bearing resistance equations considers splitting failure of the plate

15. What are the proper gage distances for this L8x4x1/2 with 2 bolts in the long leg and 1 bolt in the short leg? 3” 3” 2-1/2” 3”, 3” and 2-1/2” AISC [1-46] USE AISC MANUAL

16. In the above equation for shear of bolts with threads excluded, the 0.5 includes a 0.62 for shear and a 0.8 for what? Connection length effect

17. If bolts used in combination with welds, they should be designed as slip critical, with slip prevented at the required strength level. Why? The bolts will not bear on the plate unless welds have failed and the bolts can slip; therefore, they should be designed as slip-critical with the f of 0.85, since slip would be associated with a reduction in strength

18. In this equation for slip-critical connections, the resistance factor, f, varies depending upon what? Whether slip is prevented as a serviceability limit state or a strength requirement

19. In the AISC spec, the minimum edge distance, Le, depends on what? Le The diameter of bolt and the condition of the edge – if it is rolled, thermally-cut, or sheared (AISC Table J3.4)

20. NOTE: NOT COVERED ON 1st MIDTERM For A325N bolts in bearing-type connections subject to combined shear and tension, the tensile stress demand must be less than the available tensile stress, F’nt, which also must be less than ___? 0.75 Fub = 90 ksi

21. Even though the upper limit on the block shear limit state includes a rupture component and a yield component, it is primarily a rupture limit state. Therefore, the f factor is ___? 0.75