Figure 3.3.2: The equivalent bar, hinged at both ends,
of the slab strip Figure 3.3.2: The equivalent bar, hinged at both ends,
of the slab strip
In this example, slab s1 is hinged at both ends with width h=170 mm, and span l=4.00 m. Τhe design stress resultants, result from the slab's self-weight and covering loads and a live load q=5.00 kN/m2.
The analysis models the slab as a strip of width 1.00 m. The self-weight of concrete is 25.0 kN/m3 therefore:
Self-weight: go=0.17mx1.00mx25.00kN/m3 =4.25 kN/m
Covering: ge=1.00mx1.00kN/m2 =1.00 kN/m
Total dead loads: g =5.25 kN/m
Total live loads: q=1.00mx5.00kN/m2 =5.00 kN/m
The design combination for the ultimate limit state derives from the design load psd=γg·g+γq·q which in this case is:
psd=1.35g+1.50q=1.35x5.25+1.50x5.0=14.59 kN/m,
therefore, the stress resultants used for the slab design, derive from the expressions:
V Ad =-V Bd =14.59x(4.00/2)=29.18 kN
M md =14.59x(4.002/8)=29.18 kNm