Thiết kế bê tông cốt thép - Advanced Structural Concrete Design

CE 5510 - 2004 Advanced Structural Concrete Design CE 5510 - 2004 Flat Slab System • Column Heads • Division of Panels • Deflection • Crack Control • Shear • Arrangement of Reinforcement CE 5510 - 2004 Class Objectives •Identify the types of slab construction, summarizing the advantages and disadvantages of each •Explain the methods of analysis of slabs •Determine the design moments of one-way and two way slabs •Design of flat slabs covering: division into strips, edge and corner columns, punching shear and provision of shear reinforcement CE 5510 - 2004 Recommended Reading • James G. MacGregor, “REINFORCED CONCRETE: Mechanics and Design”, 3rd Ed., Prentice-Hall, 1997, Ch. 13 and 14. • Allen, A. H., “REINFORCED CONCRETE DESIGN TO BS8110 SIMPLY EXPLAINED”, E&FN Spon, London 1988, Ch. 14 •The next few slides are from the Reinforced Concrete Council CE 5510 - 2004 Types of slabs CE 5510 - 2004 CE 5510 - 2004 CE 5510 - 2004 Flat Slab CE 5510 - 2004 CE 5510 - 2004 [...]... sides CE 5510 - 2004 Moment CE 5510 - 2004 Restrained Corners CE 5510 - 2004 Table of Values CE 5510 - 2004 Table of Coefficients CE 5510 - 2004 Adjusted CE 5510 - 2004 Flat Slabs CE 5510 - 2004 Flat Slabs - Analysis CE 5510 - 2004 CE 5510 - 2004 CE 5510 - 2004 Flat Slab - Moments CE 5510 - 2004 Widths CE 5510 - 2004 Distribution CE 5510 - 2004 Flat Slab – Moment Transfer ... moments CE 5510 - 2004 Two-way spanning slab CE 5510 - 2004 CE 5510 - 2004 Mid Span Moments - corner supported CE 5510 - 2004 Approximate moment in one direction in slabs supported on columns at corners CE 5510 - 2004 Midspan moment - edge supported CE 5510 - 2004 Approximate distribution of moment in one direction in slabs with symmetrical supports on four sides CE 5510 - 2004 Moment CE 5510 - 2004 Restrained...CE 5510 - 2004 Analysis of Slabs course CE 5510 - 2004 One-way spanning slab CE 5510 - 2004 Simplified CE 5510 - 2004 Two way action – A rectangular panel supported on all four side • Curvature more severe along lx • Moment is short span higher • Evaluation of moment is complex as behaviour is highly indeterminate CE 5510 - 2004 Consider two strips AB and ED at mid-span Deflection at central... mid-span Deflection at central point C is the same Deflection of udl beam = 5wl 4 384EI ∆ = kwl 4 CE 5510 - 2004 ∆AB = k nAB ly4 ∆DE = k nDE lx4 nAB and nDE are portions of total load intensity transferred to AB and DE respectively Since ∆AB = ∆DE , n AB 4 x wl = 4 4 l y + lx nDE = wl 4 y l +l 4 y 4 x CE 5510 - 2004 nDE > nAB Shorter span strip, DE, supports heavier portion of load and is subject to larger