1 / 32

(1) Materials

(1) Materials. Reinforced Concrete VS Steel. Materials. Reinforced Concrete . Advantage. good resistance to weather & chemical, and good sound and thermal insulation

lewis
Download Presentation

(1) Materials

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. (1) Materials Reinforced Concrete VS Steel

  2. Materials Reinforced Concrete Advantage • good resistance to weather & chemical, and good sound and thermal insulation • the structure system is more rigid, thus, less severe problem associated with sway deflection, floor vibration, and local column buckling • higher fire resistance • minimal maintenance is required • materials required to make concrete are readily available in the local market, thus no pre-ordering is necessary • local contractors are firmly familiar with RC construction • can be cast into any versatile shape, thus, allow more flexible design • fairly tolerable on last minute changes from Client and Architect • waterproofing can be easily applied with different degree of waterproofing • can produce a good finished surface, thus, no painting is necessary

  3. Materials Reinforced Concrete Disadvantage • general heavier and hence more expensive foundation resulted • special care must be taken to ensure esthetic appearance against cracks induced by creeping and shrinkage effects • intensive amount of falsework and shuttering are required • easily affected by weather condition, this will prolong construction time

  4. Materials Steel Advantage • fast construction, weather independent • flooring can be cast at the same time where formwork are provided by un-propped corrugated steel decking • lightweighted, thus, less expansive foundation can be designed (i.e. shallow foundation.) • assembly is simple, since all members can be pre-fabricated prior to delivery to site • structure tends to be shallower in structural depth, thus, more space will be provided for service routing • with high strength to weigh ratio, suitable for long span construction.

  5. Materials Steel Disadvantage • Long pre-ordering and delivery time would be required since majority members are to be import from overseas • Early decision on member size & connection details are required so as to allow for ordering and shop drawing preparation. • Steel members require special treatment and protection on fire & corrosion. • Special surface treatments are needed: • Low cost – Sprayed System (Mineral fibre sprayed systems, Vermiculite/gypsum/cement system) • External System (Mineral fibre boards/batts, Vermiculite/gypsum boards, Plasterboard) • Preformed System • Intumescent Coatings • Water or Concrete filled structural hollow sections • Concrete casings

  6. Materials Steel Disadvantage • frequent maintenance is required • skilful labors are required for fabrication, erection, and welding • large area on site is required for storage of structural member prior to erection • sensitive to temperature change and vibration • steel members will deflect appreciably under total load, needs pre-cambering • fabrication needs heavy plant and crane

  7. (2) Structural Systems Vertical Load Supporting System Lateral Load Supporting System (x & y directions)

  8. Structural Systems Cantilever without back span Columns do not vertically align Too long cantilevers Cantilever from column without back span Heavy loading on long span transfer beam Long Slender Columns

  9. (3) Structural Forms Floor Supporting Systems

  10. Structural Forms w L (Floor Supporting System) Deflection depends on: • Shear α L • Moment α L2 • Deflection α L4 • Span • Structural Depth • Loading • Restraints

  11. Structural Forms Different forms of Bracing (Bracing)

  12. Athletic Centre, Sydney, Australia

  13. State Hockey Centre

  14. Irregular Form

  15. Federation Square

  16. (4) Preliminary Member Sizing

  17. Typical service zone requirements

  18. Reinforced Concrete

  19. Steel * Avoid if high point loads; increase Ireq by 1.3 + Precamber by L/250

  20. Typical column size

  21. Appendix: Preliminary design charts

  22. Appendix: Preliminary design charts (cont’d)

  23. Appendix: Preliminary design charts (cont’d)

  24. Appendix: Preliminary design charts (cont’d)

  25. Appendix: Preliminary design charts (cont’d)

  26. Appendix: Preliminary design charts (cont’d)

  27. Appendix: Preliminary design charts (cont’d)

  28. (4) References • Fuller Moore, Understanding Structures, Boston, WCB/McGraw-Hill, 1999. • Institution of Structured Engineers, Manual for the design of reinforced concrete building structures, London, the Institution, 1985. • Institution of Structured Engineers, Manual for the design of steelwork building structures, London, the Institution, 1989. • Ove Arup & Partners, Structural scheme design guide, London, Arup Research & Development, 1998.

More Related