Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Paper format. National Examinations, May 2013 — 98-Civ-A2 Elementary Structural Design, 3-hour duration, CLOSED BOOK (handbooks and textbooks permitted, no notes). Seven questions are printed: Part A (A1–A3, steel), Part B (B1–B3, reinforced concrete) and Part C (C1, timber). The candidate answers two from Part A, two from Part B and the one question in Part C — five solutions in total, all of equal value. All seven are solved here, because the set is a study resource. All loads shown on the figures are unfactored; NBCC load combination 1.25D + 1.5L is applied throughout. Solutions are to CSA-S16 (steel), CAN/CSA-A23.3 (concrete) and CSA-O86 (timber), as the paper directs.
Reference texts.
Check — assumptions carried through this paper. (1) The 60 kN, 50 kN, 40 kN, 200 kN, 250 kN and 300 kN forces on Figures A1–B3 are specified live loads, so a load factor of 1.5 is used; concrete self-weight is factored at 1.25. (2) Steel members are assumed continuously laterally supported unless an unbraced length is printed — no unbraced lengths appear on this paper. (3) In Figure B2 the "65 typical" dimension is taken as the distance from the tension face to the centroid of the bottom bars, and the 15M stirrups are assumed at 300 mm on centre in each stem (the figure gives no spacing). (4) CSA O86 Table 6.3.1B Beam-and-Stringer specified strengths for D.Fir-L No.1 are used in C1.
