The 'radius of relative stiffness' l in rigid pavement design is given by:
Choose the correct answer
l = Eh/k
l = (Eh³/[12(1−μ²)k])^(1/4)
l = h/k
l = k/Eh
Correct Answer
B. l = (Eh³/[12(1−μ²)k])^(1/4)
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l = (Eh³/[12(1−μ²)k])^(1/4) where E = modulus of elasticity of concrete, h = slab thickness, μ = Poisson''s ratio (0.15), k = modulus of subgrade reaction (MN/m³). l characterises the stiffness of slab relative to foundation; it appears in Westergaard''s stress equations. Larger l → stiffer slab, more load spreading.
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