Q9. Consider an elevated concrete floor slab that is 85 mm thick. Sheathing will be actual 19.1 mm { inch) plyform class 1, with grains facing across supports. Nominal 50 x 200 mm (2 8 inch) Hemlock - fir will be used for joists, and nominal 100 x 200 mm (4 x 8 inch) Southern pine will be used for stringers. Commercial 20_8 kN shores will be used. Assume that all members are continuously supported over two spans. Maximum deflection of form members will be limited to {/240. Use the minimum value of live load permitted by ACI being 2.4 kPa, and ensure the minimum design load permitted by AClof 4. B kPais considered. Given that centre to centre (c/fc) joist spacing is 730 mm governed by bending, and c/c stringer spacing is 1,980 mm governed by bending, determine: al The maximum allowable concrete density. (S Marks) b} The cfc shore spacing, assuming concrete density is 2,403 kg/m3. The maximum spacing value is required to be rounded to the nearest 10 mm. (4 Marks) {Type in your final answers in the text box below, and upload full handwritten calculations to the Moodle immediately after you have submitted the quiz.)