Now showing 1 - 7 of 7
  • Publication
    An Experimental Investigtion of Spatial Repeatability
    (Inderscience Enterprises Limited, 2000) ; ;
    The results of an experimental road research project are presented which demonstrate the existence of spatial repeatability and show patterns of axle impact forces along a pavement. As part of the project, a section of highway near Paris, France, was instrumented with 18 weigh-in-motion sensors. Data was collected for a large number of vehicles over fourteen days between June 1994 and May 1995. For all the vehicles, the impact factors were calculated and typical graphs are presented which show the variation of impact factor with distance along the sensor array. Mean impact factors and coefficients of variation are also presented and differences between steel and air suspensions are highlighted. The influence of vehicle speed on maximum impact factor is also considered.
      374Scopus© Citations 13
  • Publication
    Assessment of the Accuracy and Classification of Weigh-in-Motion Systems: Part 2 European Specification
    This is the second part of a two-part paper which addresses the issue of accuracy in weigh-in-motion (WIM) systems. The first part develops the statistical background necessary for any system of accuracy classification applied to a WIM system. This second part describes a draft European specification for the weigh-in-motion (WIM) of road vehicles, prepared by the COST 323 management committee. The philosophy behind the specification is outlined and the basic structure detailed. The specification gives an indication of what WIM accuracy might be achievable from sites with particular characteristics. There is a comprehensive review of methods of calibrating and testing WIM systems. Four types of calibration/test condition are described for tests using statically pre- or post-weighed vehicles. Accuracy classes are defined on the basis of the width of the confidence interval within which the measured results lie. Confidence interval widths arc specified for gross weights and weights of individual axles among other things. The percentage of test results which are required to fall within the confidence intervals is a function of the test conditions and the number of test runs. Examples using real WIM data illustrate the use of the specification.
      1187
  • Publication
    WAVE - A European Research Project on Weigh-in-Motion
    (National Traffic Data Acquisition Conference, 1996-05-05) ;
    WAVE (Weigh-in-motion of Axles and Vehicles for Europe) is a research project, part-funded by the European Commission, with the objective of improving the accuracy and performance of Weigh-in-Motion (WIM) technology. It has a budget of the order of $ 2 million and will run from mid 1996 to mid 1998. It has close links and a substantial overlap of membership with COST323, a pan-European group with representatives from about 20 countries which coordinates nationally funded activities relating to WIM. The principal objectives of WAVE are: (i) to improve the accuracy of WIM systems, (ii) to develop a prototype pan-European WIM database, (iii) to develop calibration and testing procedures for WIM system performance and accuracy, particularly for cold climates and (iv) to develop a prototype fibre optic WIM sensor
      276
  • Publication
    Report of Current Studies Performed on Normal Load Model of EC1-Part 2. Traffic Loads on Bridges, 5(4),
    This report gives results of some new studies performed to validate the European road traffic load model proposed by the Eurocode EC1. Weight in motion has developed greatly in the last ten years and confidence in the accuracy of recorded data has increased significantly. Traffic data recently obtained from a number of representative European sites are used to re-calibrate the codified main load model of the European bridge loading code, Eurocode 1 Part 3. A wide range of real and virtual bridge forms were chosen for the study. Simulations were performed using free-flowing and jammed traffic. Load effects generated were determined and statistical extrapolations were performed, where appropriate, to determine characteristic values for the load effects. Some of the assumptions used in the derivation of the original loading model were re-assessed.
      595
  • Publication
    Test of WIM Sensors and Systems on an Urban Road
    This paper describes a large scale test of six WIM systems and four additional sensors on an urban roadway in Zürich, Switzerland. Gross weights from some thousands of statically weighed vehicles were used to determine the levels of accuracy for each system, with reference to the new draft of the European specification on WIM (COST323). The accuracy of axle weights was not tested. The WIM sensors, which included one prototype were tested with the assistance of a recording and processing device supplied by the organiser. Most systems encountered some problems, failures and faults, under the carefully controlled conditions of the 30 month test. However, these were generally solved by the suppliers after some delay. Statistics are provided on overall levels of accuracy and on trends with season and time. In addition, a brief history of system malfunctions and failures is provided. Nevertheless the scope of the conclusions are limited by the traffic conditions and the test plan.
      940
  • Publication
    Weigh-in-Motion: Recent Developments in Europe
    (International Society for Weigh-In-Motion, 2005) ;
    This paper provides a review of recent European developments in WIM. Pan-European and national projects are reported plus developments in sensor technologies and system design. Recent developments in multiple-sensor WIM systems are given particular attention. The coming of prototype fully-automatic overload systems is discussed and the technologies and legal framework necessary for their success. The commercialisation of Bridge WIM in Europe since the ICWIM3 is considered and the continued development of this technology towards almost maintenance-free systems. WIM applications are also discussed including pavement and bridge design and assessment.
      1004
  • Publication
    Effects of Traffic Loads on Road Bridges - Preliminary Studies for the Re-Asessment of the Traffic Load Model for Eurocode 1, Part 3.
    WIM has developed greatly in the last ten years and confidence in the accuracy of recorded data has increased significantly. Traffic data recently obtained from a number of representative European sites are used to re-calibrate the codified main load model of the European bridge loading code, Eurocode 1 Part 3. A wide range of real and virtual bridge forms were chosen for the study. Simulations were performed using free-flowing and jammed traffic. Load effects generated were determined and statistical extrapolations were performed, where appropriate, to determine characteristic values for the load effects. Some of the assumptions used in the derivation of the original loading model were reassessed.
      895