Premature failures of asphalt wearing courses on newly constructed crushed stone base course

Over the past number of years there have been quite a number of road construction projects where asphalt wearing courses – that were paved on newly constructed crushed stone base courses - have failed prematurely. A similar paper was written on this same subject 20 years ago and the question is asked: What has changed? These differences and advances in analysing technique and methodology are highlighted from lessons learnt. In these new cases the detailed observation of the crack manifestation occurred very early after construction during the traffic accommodation phase or virtually directly after opening to traffic. Extensive investigations were conducted on all the projects to determine the cause of the failures. In some cases certain of these investigations served as evidence in mediation and arbitration cases. Such investigations can be very complex and as always a number of factors can contribute to such early failures. In these cases the objective conclusions reached to determine actual mechanism of failure is based on a variety of new investigation techniques and methodologies which have withstood peer review supported by paper trails. This paper is aimed at collating the data and comparing the outcome of these investigations and identified common causes for the failures and to report as lessons learnt. Therefore in this paper techniques and approaches are described with typical case evidence as demonstration to show how such premature failures should be investigated to arrive at the most probable cause or origin of distress.


  • English

Media Info

  • Pagination: 15p
  • Monograph Title: 11th Conference on Asphalt Pavements for Southern Africa: CAPSA15, 16-19 August 2015, Sun City, South Africa

Subject/Index Terms

Filing Info

  • Accession Number: 01597152
  • Record Type: Publication
  • Source Agency: ARRB
  • Files: ATRI
  • Created Date: Apr 22 2016 11:17AM