Title: Preface
Author(s): L. Francken, A.O. Abd El Halim, D. Taylor
Paper category : conference
Book title: Fourth International RILEM Conference on Reflective Cracking in Pavements - Research in Practice
Editor(s): A. O. Abd El Halim, D. A. Taylor
and El H. H. Mohamed
Print-ISBN: 2-912143-14-4
e-ISBN: 2351580265
Publisher: RILEM Publications SARL
Publication year: 2000
Pages: XIII - XV
Total Pages: 1
Language: English

The most common method for the rehabilitation of cracked pavements has been the use of bituminous overlays. However, unless high performance designs and materials and proper construction methods and techniques are used, cracks often propagate through the new overlay during the first years of service. This mode of distress, traditionally referred to as "reflective cracking" is one of the main causes of premature pavement deterioration. This phenomena, which often appears when a layer of asphalt material is placed on top of discontinuous base, can have many different aspects, in accordance with the large number of factors governing the mechanism of crack initiation and propagation through a road structure. Highway maintenance authorities wolrd-wide are in need of economic, efficient and lasting solutions to mend this complex problem.

The first internationally coordinated action given in response to this issue came from Professor J.M. Rigo of the University of Liège, who created in 1987 the Technical Committee 97-GCR "Application of Geotextiles to Crack Prevention in Roads".

Two RILEM Conferences on Reflective Cracking in Pavements, RC89 and RC93, were organized by that committee and the University of Liège in 1989 and 1993, respectively. These events have demonstrated that many innovative systems are now commonly implemented, and the proceedings of these conferences remain unmatched sources of information on the reflective cracking issue:

- RC89 pointed out the main factors and mechanisms involved in the initiation and propagation of cracks. A first inventory of systems and approaches available to prevent cracking was presented.

- At the RC93 Conference, emphasis was on the theoretical and experimental research required to optimize solutions. The foundations were laid for a classification of products and overlay systems with the aim of setting up a procedure for selection and design.

In 1993 the RILEM Technical Committee 157-PRC "Systems to Prevent Reflective Cracking in Pavements" was formed with a broader field of tasks than TC97-GRC to deal not only with geotextiles and related products, but also with other innovative materials and technical solutions involved in the prevention of crack reflection such as:

- preventative measures to be taken in new construction projects,

- repair and rehabilitation work to be carried out prior to the application of an interlayer,

- practical problems during laying and construction, and

- long-term performance of overlay systems

A third conference, RC 96, was organized in Maastricht, in October 1996, by the new RILEM Technical Committee 157-PRC, the Belgian Road Research Centre and the Centre for Research and Contract Standardization in Civil and Traffic Engineering (CROW) and Delft University of Technology, both of the Netherlands.

- At RC96 the focus was on the design and performance of overlay systems - full scale performance verifications and practical field experience.

- The Committee seized this opportunity to gather the information needed to finalise a state-of-the-art report on the prevention of reflective cracking in pavements. This resulted in the production of the RILEM Report N°18 that was published in 1997, and which is, so far, the most comprehensive overview of the subject.

The main objective of the RILEM Technical Committee 157-PRC in organizing this Fourth International Conference on Reflective Cracking in Pavements - Research in Practice is to gather information on the application of research in construction. Eleven years have passed since the first conference and almost four years since the last, in 1996. New innovative techniques have been developed and employed in field trials; new mix design procedures from the Strategic Highway Research Program, new construction methods and equipment, performance data from test sections and new advanced materials are being utilized in the search for more reliable solutions to reflective cracking. As we enter the year 2000 it is time to evaluate the application of the previous technologies and trials of recent innovations.

Fifty papers have been selected and are organized in the proceedings under seven major topics:
- Design and analysis
- Resistance to cracking
- Crack prevention - Modified mixes
- Crack prevention - Stress relief layers
- Crack prevention - Pre-cracking
- Crack prevention - Pavement reinforcement materials
- Evaluation of prevention techniques

The interest in this conference and the quality of the contributions are testimony to the major research efforts continuing around the world to mitigate the effects of reflective cracking in roadway pavements.

Louis FRANCKEN, Dr. Sc.
Chairman RILEM TC 157-PRC

A.O. Abd El HALIM, Ph.D., P.Eng.,
Don TAYLOR, PhD., P.Eng.
Conference Co-Chairs

Online publication: 2009-12-23
Publication type : full_text
Public price (Euros): 0.00