A rectangular slab of concrete in a highway as shown in Figure P15–29 can be considered...

A rectangular slab of concrete in a highway as shown in Figure P15–29 can be considered to have sides parallel to the road free and sides perpendicular to the road simply supported. The critical buckling stress is shown to be

where for medium strength concrete we assume E = 3.5 × 10⁶ psi and v = 0.20. Let the slab dimensions be length a = 120 in., width b = 96 in., and thickness t = 6 in. Determine the uniform temperature increase in the slab that will buckle it. Use a finite element code to solve this problem.