Identification of road defects, causes of road deterioration and relationship among them for bitumen penetration macadam roads in Sri Lanka

Abstract

The study was particularly concentrated on identifying the causes of road deterioration, road defects and determining the most important parameters which could be used to predict the rate of deterioration particularly in Bitumen penetration macadam roads. A comprehensive literature review was conducted with literature related to both local an international context to determine the road deterioration factors, road defects, rate of deterioration ..... etc both locally and foreign countries. Moreover, the literature review was accompanied with the road condition surveys where sophisticated equipments were used in developed countries while manual data collection methods were used in developing countries like ours. In achieving the above objectives, a suitable surface condition survey form was developed. Surface condition survey form was accompanied with road surface information, road geometry, sand sealing history and road deformations. Traffic data and sand sealing history were obtained from Provincial Road Development Authority (PRDA) and the rest was obtained by field observations. Data collection was carried out in selected Bitumen penetration macadam roads for about nine months. Cracks, potholes, edge defects, depressions, corrugations are the significant road defects observed in the field. Traffic, age, road geometry, weather, drainage, construction quality as well construction material, maintenance policy play the major role as road deteriorate agents. Potholes and cracks were mainly considered in the field observations of road deformations. The data was analysed by usingthe statistical softwares SPSS and SAS. Category data was used for data analysis and statistical tests were carried out to check the significance of the road deterioration agents. It was found that both potholes and cracks were having significant relationship with age as well as traffic.