DBPapers
DOI: 10.5593/SGEM2014/B62/S27.059

ANALYSIS OF THE CRACKING PROCESS OF LEAN CONCRETE ROAD BASES

M. Pradena, L. Houben
Wednesday 1 October 2014 by Libadmin2014

References: 14th International Multidisciplinary Scientific GeoConference SGEM 2014, www.sgem.org, SGEM2014 Conference Proceedings, ISBN 978-619-7105-21-6 / ISSN 1314-2704, June 19-25, 2014, Book 6, Vol. 2, 457-464 pp

ABSTRACT
Lean Concrete Bases (LCBs) are an interesting alternative with respect to sustainable infrastructure. In fact, because of the structural properties and resistance to erosion of LCBs, they provide long-term support to the overlaying pavement layers. Even more, these overlaying layers can be replaced while maintaining the LCB. Even when LCBs are used in flexible and rigid pavements because of their beneficial properties, the LCBs suffer from deformations, starting at the ‘green’ state, as a result of shrinkage and changes in temperature. As the LCBs cannot move freely, cracks are produced. These cracks have the potential to reflect through the overlaying pavement layers. The objective of the present paper is to analyse the longitudinal and transversal cracking process of LCBs. For that, a model previously published by the authors is used. The modelling was compared with field investigations on concrete pavements in Chile and Belgium. The model predicts the cracking process in LCBs (time of occurrence of the cracks, magnitude of the cracks, etc.) without and with saw-cutting. These modelling results are fundamental to the structural design and analysis of cracks reflective in the layers over the LCBs. It was possible to conclude, for instance, about the magnitude of the transverse crack width in LCBs, the reduction of more than 70% of the crack width through saw-cuts, the induction of earlier cracks (40 hours), or the negligible effect of the longitudinal cracks in LCBs on reflective cracking in the pavement surface.

Keywords: Lean Concrete, Roads, Shrinkage, Cracks.