A rigid pavement is to be designed to provide a service life of20 years and has an initial PSI of 4.4 and a TSI of 2.5. Themodulus of subgrade reaction is determined to be 300 lb/in3. Fordesign, the daily car, pickup truck, and light van traffic is30,000; and the daily truck traffic consists of 300 passes ofsingle-unit trucks with single and tandem axles, and 400 passes oftractor semi-trailer trucks with single, tandem, and triple axles.The weights for cars, pickups, light vans is two -2000 lb singleaxles, for single unit trucks are 10,000 lb steering, single axleand 22,000 lb drive, tandem axle and for tractor semi-trailertrucksare 12000 lb steering, single axle, 18,000-lb drive, tandemaxle and 50,000 lb, trailer, triple axle.Reliability is 95%, theoverall standard deviation is 0.45, the concrete modulus ofelasticity is 4.5 million ln/in2, the concrete’s modulus of ruptureis 900 lb/in2, the load transfer coefficient is 3.2, the drainagecoefficient is 1.0. Determine the required slab thickness.
