Analysis of Soil and Environmental Conditions for Resilient Pavements in the Niger Delta

The short service life of pavements in the Niger Delta has resulted in high recurrent maintenance cost of roads.

Pavement failures have been attributed to widespread weak, expansive clays and silty soils, which lead to high water table issues and poor drainage without an understanding of the mechanisms involved and an appreciation of the
adequacy of the codes used in their design. This paper explores the concepts of pavement design, assessing the necessity and functions of individual layers as well as the geological materials they are made of. The paper then identifies the weaknesses in the pavement design culture practiced in Nigeria to include poorly prepared subgrades, use of unsuitable aggregates, insensitivity to the environmental conditions among others. It further investigates the relationship between the distribution of axial load and the thicknesses of pavement layers to identify vulnerabilities particularly in the Niger Delta that can promote pavement failure. It examines the influence of moisture on the attainment of adequate compaction as well as on the resilience of pavements. The paper argues that the extensive weak subgrades and rapid variability of superficial geology such as exist in the Niger Delta demands a review of the national design code to accommodate the peculiarities of the region. To ensure resilient pavements, understanding
soil and environmental conditions is paramount. This involves integrating soil-structure interaction principles, ground improvement and stabilization techniques, as well as risk assessment methodologies to enhance structural integrity and sustainability of pavements.