PRIMARY CAUSES OF ROAD PAVEMENT FAILURE AND POSSIBLE SOLUTION

ABSTRACT
This project investigates the primary causes of Road Pavement Failure and Possible Solution (a case study of Iree-Ibokun road). Various tests are carried out on soil samples colleted from failed areas of the road such as CBR test, sieve analysis test, liquid limit, Plastic limit test, Plastic index test and compaction test. The foundation failures of the road pavement observed are caused by excess ground water penetrated into the base and sub-base courses and geotechnical properties of the soil were also responsible for the failure of the road pavement such as: inadequate compaction, water infiltration through edge break, lack of adequate drainage and unsuitable soil. From location A,B and C the results of sieve analysis ranges from liquid limit (LL) is 51-20% Plastic limit (PL) is 31.11% and plastic index is 20.89% respectively, CBR of the sample ranges from 24%, - 26% respectively. The values are not meet the requirement of sub-base and base courses which suppose to have not less than 80% respectively. To obtain optimum performance of the road, the causes identified above should be corrected