Module 4: Pavement Design

Lecture 29 Rigid pavement design

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Problems

1. Design size and spacing of dowel bars at an expansion joint of concrete pavement of thickness 20 cm. Given the radius of relative stiffness of 90 cm. design wheel load 4000 kg. Load capacity of the dowel system is 40 percent of design wheel load. Joint width is 3.0 cm and the permissible stress in shear, bending and bearing stress in dowel bars are 1000,1500 and 100 $kg/cm^2$ respectively.
2. Design the length and spacing of tie bars given that the pavement thickness is 20cm and width of the road is 7m with one longitudinal joint. The unit weight of concrete is 2400 $kg/m^3$, the coefficient of friction is 1.5, allowable working tensile stress in steel is 1750 $kg/cm^2$, and bond stress of deformed bars is 24.6 $kg/cm^2$.