Investigation of the Causes of Flexible Pavement Failure along Three Selected Roads in the Niger Delta Region of Nigeria

This study investigated the causes of flexible pavement failure along three major roads in the Niger delta region of Nigeria. The three selected roads are Ogbia-Nembe road, East-West Road and Port Harcourt-Aba. Different types of failure such as alligator cracks, rutting, corrugations, etc., were observed on the selected road alignments. Pavement condition and traffic surveys were carried out on the selected road locations to ascertain their causes of failure. The study method involved the use of structured questionnaires which were distributed mostly to civil engineers and other construction stakeholders. A 5-point Likert scale was used to analyze the questionnaires retrieved from the respondents. The results of data analysis of the questionnaires and traffic survey showed that lack of laboratory investigation of construction materials, poor quality of the construction materials, lack of maintenance culture, poor soil condition of the road, inadequate drainage systems and overloading of road pavements are the major factors that are responsible for flexible pavement failures of the three selected roads in the Niger delta.