Paper format. 98-Civ-B2 Advanced Structural Design,
December 2016, three hours, closed book (design handbooks and textbooks are permitted,
no notes). Seven design questions; any five constitute a complete paper and all
questions are of equal value (20 marks each). Because the whole paper is a study
resource, all seven questions are solved here. Page 1 states that all
loads shown on the figures are unfactored, and supplies the design data used
throughout.
Reference texts.
- CSA S16:19, Design of Steel Structures — Clauses 11 (classification),
13.4 (shear), 13.5 (bending), 13.7 (bracing for plastic design), 13.8 (axial
compression and bending), 14 (plate girders), 17 (composite beams).
- CSA A23.3:19, Design of Concrete Structures — Clauses 8 (limit states),
9.8 (deflection), 10 (flexure and axial load), 11 (shear), 15 (footings),
18 (prestressed concrete).
- CISC, Handbook of Steel Construction, 12th ed. — section properties and
the beam-column selection tables.
- National Building Code of Canada 2020, Part 4 — load combinations.
- M. P. Collins and D. Mitchell, Prestressed Concrete Structures —
permissible-stress design and tendon-zone construction.
- R. C. Hibbeler, Structural Analysis, 10th ed. — continuous-beam and
rigid-frame analysis.
Design data (page 1 of the examination paper)| Quantity | Symbol | Value |
|---|
| Concrete | f'c | 30 MPa |
| Structural steel | Fy | 350 MPa |
| Reinforcing bar | fy | 400 MPa |
| Prestressed concrete at transfer | fci | 35 MPa |
| Prestressed concrete | f'c | 50 MPa |
| Modular ratio | n | 6 |
| Strand tensile strength | fult | 1750 MPa |
| Strand yield strength | fy | 1450 MPa |
| Initial strand stress | finitial | 1200 MPa |
| Loss of prestress | Δfp | 240 MPa |
| Effective strand stress | fse = 1200 − 240 | 960 MPa |
Check — load factors. Page 1 says only that
“all loads shown are unfactored”; it gives no dead/live split, so no NBCC
combination can be formed exactly. Every solution below applies a single factor of
1.5 to the loads printed on the figures and 1.25 to
self weight that the solver itself introduces (girder, slab, frame members), and states
that assumption where it is used. The choice scales the required resistances but changes
neither the collapse mechanisms, the section classifications, nor any interaction
ratio, so the engineering conclusions are unaffected. Serviceability checks
(prestress stresses, deflections, bearing pressure) use the unfactored loads as
printed.
