Design of Rigid Pavement for Oke- Omi Road, Ibadan, Nigeria

Abstract

Rigid pavements are often preferred to flexible types due to their higher durability and ease of maintenance also to reduce early road failure and increase its longevity. This study redesigned a deteriorated segment of Oke-Omi flexible road pavement as a rigid pavement. The pavement thickness was derived using the American Association of State Highway and Transportation Officials (AASHTO) design method. A programme using a spreadsheet was developed to facilitate the design process. The sieve analysis result showed that the soil was poorly graded. The soil has a low plasticity index of 28.1% (liquid limit 46.2%, plastic limit 18.1%); the Maximum Dry Density and Optimum Moisture Content were 1999 g/cm³ and 10.8% respectively. The California Bearing Ratio of the soil was 48.43% which shows that the subgrade strength was adequate. The computed Estimated Single Axle Load (ESAL) for both the base year and the projected year are 6.74x10⁶ and 100x10⁶ single axle respectively. The design process yielded the pavement thickness of 240 mm and 380 mm for the base year (2017) and projected year (2037) respectively. A rigid pavement of adequate thickness was designed for the deteriorated segment of the Oke-Omi road.