Browsing by Author "Feighan, Kieran"

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    Development and Implementation of a Simplified System for Assessing the Condition of Irish Regional and Local Roads
    Mulry, Brian; Feighan, Kieran; McCarthy, John (2015-06-04)
    The surface condition of road pavements is a vital element in pavement management to prioritize projects, select appropriate treatments and make the best use of available resources. In Ireland, the overall road network of 99,008 kilometres includes 5,415 kilometres of National Roads and 93,593 kilometres of Regional and Local Roads. To evaluate the condition of the Regional and Local Roads, a simplified pavement inspection methodology, the Pavement Surface Condition Index (PSCI) rating system, has been developed. The PSCI system is outlined in a new Rural Flexible Roads Manual published by the Department of Transport, Tourism and Sport. The manual describes types of defects for Irish roads and provides a simple 1 to 10 scale based on pavement defects to visually rate pavement surface condition. The condition survey is carried out from a moving vehicle and the assigned PSCI rating is recorded and geo-referenced using an innovative tablet and App device. The results of the rating system provide a standardized approach to link pavement distress to specified maintenance treatment measures for Irish roads. The implementation of the Rural Flexible Roads Manual and PSCI rating system involved the development of new IT solutions and the training of local authority personnel in 31 Local Authorities. The simplified system and App device is being used by local authorities to visually rate their rural road networks with over 45,000 kilometres of network rated to date. In addition, the PSCI was successfully used as part of a major study in 2011/12 to survey the entire network of 13,121 kilometres of Regional Roads. The overall objective is to use the results of the 1 to 10 rating to establish the existing pavement condition, and the lengths of roadway requiring various types of remedial works, both nationally and at county level. This paper describes the development and implementation of a new Rural Flexible Roads Manual and PSCI rating system using an innovative tablet and App device for Irish roads. In addition, the key role of the PSCI data in the management of the Irish roads network and experience to-date of local agencies in the use of the system is discussed.
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    Recent Developments in Pavement Management on Irish National Roads
    Feighan, Kieran; McGowan, Ray; Casey, Tom; O’Sullivan, Andrew (2015-05)
    The Irish National pavement network is Ireland’s strategic road network consisting of over 5,300 centreline kilometres of road and is managed by the National Roads Authority (NRA). There is a very significant variation across the network under a variety of headings, including pavement construction, pavement age, carriageway width, lane width, geometric design and traffic volumes carried. A large proportion of the network consists of “legacy” roads that have evolved from historic routes that are often constrained by physical or environmental conditions This diversity in road construction as well as varied traffic volumes, leads to significantly different deterioration and failure modes across the network. Constraints in the geometrical alignment also tend to alter how the route is driven, e.g. The average inter-urban speed is lower for routes with tight radius bends. Accordingly, a range of innovative measures have been adopted to customise and adapt the Authority’s Pavement Management System for the Irish National road system. The objective of this paper is to describe these innovative measures to an international audience. Pavement Condition data collection using high speed machine survey vehicles has been carried out annually on the National road network. Most of the road condition data is collected using the Road Surface Profiler (RSP) machine. The skidding resistance data is collected using the Sideways-force Routine Investigation Machine (SCRIM). In 2013, LCMS has been used to collect cracking and ravelling data on the entire network. In addition, in 2013, a Ground Penetrating Radar (GPR) survey has been carried out on the entire network to improve the pavement construction and layer thickness data. To manage this diverse network effectively, it was decided to define a series of five subnetworks by grouping similar sections such that there is considerably less variation in pavement condition, traffic and construction type. This approach enabled the service levels set for the different subnetworks to take account of the differences in traffic levels, pavement type and foundation characteristics of each subnetwork. The approach recognises the necessity to adopt progressively lower performance levels on Subnetworks 1 to 4, as compared to Subnetwork 0 (the motorway / dual carriageway network). In effect it recognises the constraints and adopts a “fit for purpose” approach. The performance levels are also used at tactical and strategic level for management of the network. There is a comprehensive managed skid resistance programme based on 100% measurement of the skid resistance of the network on an annual basis. Principles of risk equalisation have been developed with a range of skid resistance investigatory values used on the network, dependent on the road section characteristics – approaches to roundabouts and traffic lights having significantly higher skid resistance requirements than straight line nonevent sections, for example. This skid resistance policy is applied consistently across all subnetworks. The NRA corporate GIS, ArcGIS, is used to co-ordinate and cross-reference the data from a range of management systems including the PMS, Bridge Management System, Accident Database, Traffic modelling database, Routine Maintenance Management Systems among others. A new ArcGIS add-in has been developed for the NRA to allow display and querying of the imagery collected on the annual surveys.The processed video is also available to the NRA and its clients through a web browser system.