Pavement Inspection Research Articles

Applications of thermography in the assessment of masonry, airport pavements and composite materials

The paper presents some applications of infrared thermography. These are: □ Surface cleaning assessment of historic buildings. □ Inspection of airport pavements. □ Inspection of composite sheets for aerospace applications.

Investigation of causes of failures of flexible pavements: a case study of Nairobi-Thika highway

Failures of flexible pavements (bituminous roads) have been prevalent in many developing countries, a trend causing concern to both the road users and the roads authorities. In this regard, it was found necessary that an investigation be initiated to determine the possible causes of such failures, and a case study was carried out on Nairobi-Thika Highway in Kenya. The investigations were conducted in several categories to determine the pavement characteristics such as structural strength by Benkelman Beam Deflection Test (BBDT), skid resistance by British Pendulum Tester (BPT). Traffic loading by Axle load measurements, Traffic volumes by traffic counting and ageing characteristics of the type of the bitumen used by cutting cores and extracting the bitumen for the standard tests, such as penetration, ductility, bitumen content, air voids, softening point and CBR using the Light Drop Weight Tester (LDWT). The visual inspection of the pavement showed that due to the hardening of the bitumen and overloading, cracks and potholes were very common for the whole stretch of the road. Axle load data revealed that, there has been a tendency to exceed the maximum allowed axle load limits, especially until 19th august, 1999, after that the enforcement of axle load limits was tightened. This fact together with the revelation that the road is a very busy one as depicted in the traffic counts, could be one of the major causes of the road's fast deterioration. (Journal of Civil Engineering, JKUAT: 2002 7: 13-26)

Pavement Performance Analysis Applying Probabilistic Deterioration Methods

The procedure used to determine whether performance differences exist among the Ohio Department of Transportation’s (ODOT’s) 12 districts is presented. Two performance measures were used: pavement condition rating deterioration trends and distributions. The methods used to develop the performance measures from existing pavement data are presented. Five years of actual pavement inspection data were supplied. The study was limited to divided highways with four or more lanes. To develop the deterioration trends, existing data were transformed into a probabilistic deterioration model using geographic information systems and relational database software. Monte Carlo simulation was used to establish deterioration trends and a Markovian deterioration envelope. Hypothesis testing was implemented to determine which districts were performing better or worse than the state as a whole. ODOT’s northeastern districts performed worse than the state average, and rural districts performed better than the state average.

Field inspection and laboratory testing of highway pavement rutting

The main objective of this research was to investigate the contribution of pavement characteristics, traffic, and physical and mechanical properties of asphaltic mixtures to highway pavement rutting. A total of 51 pavement sections from the rural highway network in Jordan were selected for a case study. The average rut depths for these sections were measured and three cores were drilled for comprehensive laboratory testing. The investigation was performed using four approaches. The first approach considered pavement characteristics represented by surface thickness, last overlay thickness, pavement age, and subgrade California bearing ratio. The average annual equivalent single axle load was also included in this approach. The second approach included Marshall test parameters such as stability, flow, stiffness, and Marshall modulus. The third approach dealt with the effect of mixture air voids on rutting. The variables examined in this approach include air void content within the ruts, voids between ruts, voids near the pavement centerline, and the difference between centerline and rut voids. The fourth approach considered the dynamic permanent deformation characteristics of the pavement surface layer represented by the dynamic modulus. Regression analysis techniques were employed to develop statistical relationships between average rut depths and the parameters examined in each individual approach. The combined effect of these significant parameters on pavement rutting was also examined for prediction purposes. Rutting formation was found to be most dependent on the traffic loading, dynamic modulus of the bituminous mixture and its susceptibility to further compaction, and foundation soil strength.Key words: pavement rutting and characteristics, Marshall test, traffic loading, air voids, static creep, dynamic permanent deformation.

Neural network system for automated highway pavement inspection : Guralnick, S.A.; Suen, E.S.; Gu, J. Infrastructure Planning and Management Conference Proceedings, Denver, Colorado (United States), 21–23 Jun. 1993. pp. 272–276. Edited by J.L. Gifford, D.R. Vzarski and S. McNeil. American Society of Civil Engineers (1993). ISBN 0-87262-917-1

A multi-layer perceptron back propagation neural network based methodology has been developed to process and analyze moire fringes obtained with an automated highway pavement inspection system developed in our laboratory. The sensitivity, accuracy, and efficiency of the model is compared with benchmark results obtained by means of traditional techniques to evaluate the overall system performance.

Prototype Knowledge-Based System for Corrective Maintenance of Pavements

Corrective maintenance of pavements involves identifying the existing problems and selecting the most effective remedial measure to correct the deficiencies. Regular inspection and minor repairs ensure a satisfactory level of pavement performance, and it prevents the occurrence of future major problems. Due to the unbalanced proportion of too many pavements in need of repairs and too few experienced engineers to carry out the task of condition and treatment evaluation, pavement inspections and necessary repairs are irregular and are not performed as often as needed. More often than not, methods of rehabilitation are more practically available than competent engineers. The dissemination of expert knowledge about pavement inspection and treatment evaluation by means of knowledge-based systems to a wider group of engineers (such as local maintenance personnel) is needed. This paper discusses the maintenance requirements in Ontario, Canada, and presents the development of a prototype object-oriented knowledge-based system for the inspection and repair of pavements.

Parametric investigation of an automated NDE pavement inspection system

This paper describes an investigation of the principal operating and design parameters relevant to a newly developed automatic, nondestructive evaluation (NDE) pavement inspection system which produces quantitative, machine-readable data for the objective assessment of highway-pavement condition. The sensitivity, accuracy, and efficiency of system performance is treated in this paper.

Condition Evaluation of Jointed Concrete Airfield Pavement

This paper describes the development and field verification of a Pavement Condition Index (PCI) for rating jointed concrete airfield pavements. The PCI, which is a measure of pavement structural integrity and surface operational condition, is calculated based on measured distress types, severities, and densities obtained during a pavement inspection. A distress identification manual has been developed which provides a standardized reference for measurement. The PCI has been extensively field tested and validated at many airfields. It was also found to correlate closely with maintenance and rehabilitation needs. The PCI procedure has been adopted by the U.S. Air Force and is under full implementation at many airfields.