Paper ID#: 57

Paper Title: The New Generation Data Collection Regime for Pavements for Major Roads in England

Primary Author: L. Hawker

Abstract Text : The paper describes the reasons for, and use of, a new regime of data collection for the pavements of the National Roads of England, including a new machine for collecting surface condition data at the speed of the prevailing traffic, causing a minimum of disruption to road users.Historically, there has been extensive use of visual surveys for pavement surface condition assessment, but these, by their nature, are subjective and have been both expensive and the cause of extensive delays to the road users. With the ever increasing levels of traffic and the greater accent being placed on the views and wishes of the travelling public, it became imperative to further the move to machine based surveys. The network wide surveys have therefore moved from routine visual and machine surveys of the surface and structure to solely machine based surveys of the surface. Deflection surveys and a new type of visual surveys are being restricted to the project level to define maintenance work to be done.To undertake network wide surveys entirely by machine, a new generation of machine (TRACS) was implemented, based on extensive research and prototype development. These surveys are carried out at the speed of the prevailing traffic and collect data on longitudinal profile, transverse profile, texture and cracking. Surveys are undertaken on one lane in each direction of single carriageways and at least 2 lanes in each direction of dual carriageways, plus each slip road, each year. A total of more than 40,000 lane-kilometres is surveyed each year, resulting in 6 Mb of raw data per lane-kilometre. At the network level, these surveys are currently supplemented by SCRIM surveys, but research continues to relate the skid resistance, as measured by SCRIM, to the texture as measured by TRACS with a view to needing only the data from a single TRACS survey.Before confirmation of the maintenance treatment design, and of expenditure, at a particular location, the surveys undertaken on the entire network are supplemented by additional project level surveys at the particular location. These project level surveys include deflection (Deflectograph) and limited visual surveys. All of the information collected by machines is processed automatically using a single, new software package to validate, locationally reference and partially analyse the output from each of the machines (i. e. TRACS, SCRIM and Deflectograph). Together with data from visual surveys, the machine data forms the principal data source for the new Highways Agency Pavement Management System (HAPMS).The paper gives orders of magnitude of the costs of development and implementation of the new systems, set in the context of the perceived benefits of the new regime, the perceived value of the asset being maintained and the annual spend on maintenance works.