Due by Friday, March 21, 9:30am(10 Homework Points)

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1 Winter CEE454 Extra Credit Assignment Due by Friday, March 21, 9:30am Due by Friday, March 21, 9:30am(10 Homework Points) The purpose of this assignment is 1) to give you an opportunity to boost your overall homework grade, and 2) for you to demonstrate your knowledge of some key concepts we learned in this course over the quarter specifically, those that you will be using throughout the rest of your career. This assignment is partially formal and partially informal, and also based on actual field examples. The few calcs there will be should be submitted to Jeralee either by , or in paper as you would a normal homework assignment. The informal portion of the assignment comes after you have finished the calcs. I will set up a few blocks of time this week (probably starting Wednesday after lunch and Thursday), and you will need to come discuss your answers with me in order to get full credit, or me a detailed explanation (however, then I can t give you real-time feedback). Mostly I am looking to gather whether you can explain your design process, your models, and think a bit outside the box. You may collaborate on ideas, but not numbers, and you must submit an individual paper of all your own work. Show all of your work. (Note: C for Calc and D for Discussion - 2C + 1D = 2 points EC) PROBLEM 1 (2 POINTS TOTAL) An electrical contractor has taken some structural liberties with stringing conduit through one of the joists in the floor of your newly-remodeled second-floor piano room as shown below in the structural framing detail. You like to keep your superiorly energy-inefficient downstairs sauna at a toasty and steamy 105 o F, and you are dead-set on having exposed framing in this area for looks. Part C1. For ASD, is the member adequate in shear under a total applied load (D+L only)? Floor Finish is ¾ ceramic tile o/ 1-1/8 ply o/ 1 rigid (waterproof) insulation. Ignore wood self-weight. Use typical residential live load. Joists are Northern Species lumber spaced at 28 o.c. for some weird reason. Ignore span length. Part C2. You have (or plan to have) a child who is destined to be the next Baby Beethoven, which absolutely requires the immediate purchase of a Steinway Concert Grand Model D (because they are on one-time-only sale at your local Steinway-mart.) The only logical place to locate the new piano is directly above the beam with the electrical wiring. Would the beam be adequate? (Hint: Internet.) Part D1: Regardless of the results of Parts 1 and 2, you don t feel comfortable knowing there are holes poked through your floor (besides, you just spent a good chunk of change on a brand new Steinway!) and while you are enjoying your evening basting, you don t like looking at those rather unsightly holes in your wood. Suggest some solutions that would make you feel more comfortable about how your floor is performing for this joist.

2 PROBLEM 2 (6 POINTS) You are the structural engineer for a new two-story mixed-use commercial building with the profiles and plans as shown below. Roof DL = Floor DL = 10 psf. W = 15 psf, E = 1.25 psf for roof and walls contributing to roof diaphragm, E = 0.62 psf floor and walls contributing to floor diaphragm. Framing is Douglas-Fir Larch. Part C3. For ASD, find the distributed wind and seismic loads for second floor Wall 2 (in plf). Note which governs. You may discount partition loading (PL), and self-weight of walls is included in the given loads. Part C4. For ASD, find the total wind and seismic point loads for first floor Wall 11. (Think carefully.) Part D2. What concerns do you have for supporting Wall 2 under the lateral loading as described? What other elements would need to be designed in order to complete the load path? How would you approach this? Part C5. With one sheet of ½ Struct-I OSB nailed at 3,3 & 12 with 8d commons and 2x wall blocking, 3x PT sill plate per code, does Wall 11 have adequate capacity for shear? Part C6. The architect you are working with decides to split the kitchen on the first floor into a breakfast nook and cooking area. You now have a framed wall with sheathing directly below Wall 2 as shown. Determine the total lateral force in the line of the new wall, the unit shear, and specify the plywood panel nailing for ½ Struct-I OSB with 8d commons in a framed wall with 2x4 studs at 16 o.c. Part D3. You decide that Wall 11, sheathed and nailed as noted above in C5, does not make you feel comfortable with its shear capacity. What solutions can you suggest to ameliorate the shear problem here? (There is more than one answer here. Think of as many as you can.) Part C7. Find the total net overturning moment of the stacked walls from Part C6. Dead load is 15 psf for interior walls. Part C8. Specify an appropriate Simpson Strong-Tie holdown (use an HDU type) to accommodate the uplift load you found in Part C7. Make sure you specify an appropriate foundation anchor to match your holdown. (Hint: Part D4. You were given a foundation system with a slab-on-grade bottom floor. What types of anchors would be appropriate for this application if the architect changed the exterior lower floor support system to a 6 concrete stemwall, such as in a raised-floor application with a crawl space? If it were an existing building, would your answer change?

3 LATERAL ANALYSIS PARAMETERS DL: 10 psf PL: 0 psf 20.0 ft 5.0 ft DL: PL: 10 psf 0 psf 10.0 ft 20.0 ft 10.0 ft SEIS(ASD)= 0.092W (R = 6.5) WIND = 15 PSF (EXP. C)

4 40'-0" 14'-0" w/ 2x trimmer stud Wall 2 8'-0" CCQ46 Floor 2 (Roof Level) ECCQ46 40'-0" 14'-0" 25'-0" Proposed Nook Wall (Wall 12) Proposed (N) Beam 10'-6" Wall 14 Floor 1 (Floor Level) 4'-0" Wall 11 25'-0" DBL RR RR Wall 1 Wall 3 Proposed FJ Layout Original FJ Layout LIVING KITCHEN DN OPEN

5 PROBLEM 3 (2 POINTS) You have a 20-foot long wall in an 8-foot tall wood framed wall with double 2x4 top plates in the first floor of a two-story building. The wall supports 10 feet of floor and roof joists weighing cumulative total of 100 psf (including D+L) and lateral unit shear of 25 plf. Assume stud spacing aligns with joists. Part C9. For ASD, determine the number of 16d common nails needed for a double 2x4 top plate splice of 48 in length adequate to carry a chord or drag load based on the given loading. Part C10. For ASD, assuming studs are laterally braced by blocking or sheathing in both the strong and weak directions, is 16 o.c. adequate for the vertical compressive load? Part D5. Your client (the architect) is all into this green building hullabaloo and wants you to help earn his/her project some LEED points. What suggestions might you make to help reduce the amount of structural materials and impact that this project could have on the environment? (Hint: Advanced Framing )