Risk-based Inspection on Highway Assets with Category 2 Defects

Risk-based Inspection on Highway Assets with Category 2 Defects

E.O. Ekpiwhre K.F. Tee S.A. Aghagba K. Bishop 

Department of Engineering Science, University of Greenwich, UK

Department of Highways, Ministry of Works, Delta State, Nigeria

Asset Management Directorate, Transport for London, UK

30 June 2016
| Citation



This paper presents a study piloted on highway assets Category 2 defects. Imminent hazards on high-way road networks are significantly accelerated by structural deterioration of highway infrastructures. The inspection and maintenance strategy for highway infrastructure requires continuous improvements to reduce high occurrence of defective highway assets. Combined risk-based inspection (RBI) and stochastic (STOC) techniques is considered in this investigation to give an in-depth understanding of highway asset maintenance response. Appropriate data information is extracted from Network Maintenance Management System and complementary information elicited from maintenance experts as well as recommended standards. Safety inspections piloted within the period of 5 years is evaluated using the projected RBI-STOC approach. The RBI incorporates the consequences and likelihood of the defects and the combined STOC techniques utilised defines the actual maintenance interval operated. The RBI-STOC approach proposes reclassification of highway asset defect repair intervals, appropriate maintenance task response and efficient maintenance prioritisation of highway assets in equivalence with contribution to system average mean time to repair and downtime.


category 2 defects, probability distribution, risk-based highway assets management, risk-based inspections, safety inspection


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