A new explanation of pavement cracking from top to bottom: the visco-elasticity of asphalt materials?

Title: A new explanation of pavement cracking from top to bottom: the visco-elasticity of asphalt materials?
Author(s): P. Tamagny, L. Wendling, J. M. Piau
Paper category : conference
Book title: Fifth International RILEM Conference on Reflective Cracking in Pavements
Editor(s): C. Petit, I.L. Al-Qadi and A. Millien
Print-ISBN: 2-912143-47-0
e-ISBN: 2912143764
Publisher: RILEM Publications SARL
Publication year: 2004
Pages: 425 - 432
Total Pages: 8
Nb references: 3
Language: English

Abstract: Cracking from top to bottom is one of the recognized way of deterioration of pavements. The diversity of climates and traffic conditions for which this phenomenon is observed leads to formulate numerous possible causes for this type of cracking (complex tyre/ pavement surface interaction, ageing of binders, thermal cycles, etc). However among these explanations the structural behaviour of pavements itself is seldom mentioned, since wear courses are supposed to work in compression under traffic loads.The aim of this paper is to show that this last assumption may be wrong, in some cases because of the viscoelastic behaviour of asphalt materials and because of their high thermal susceptibility. Some results issued from laboratory experiments and detailed analyses of the pavement structural behaviour are used as a proof. The starting point is based on the study of crack propagation in bituminous materials obtained with the MEFISTO laboratory test [1], which shows cracks occurring from top to bottom in some circumstances, whereas the cracks were initially expected to develop from bottom to top. In fact the visco-elastic stress redistribution justifies the phenomenon. Then it is shown from numerical simulation of bituminous pavements that due also to viscoelasticity the wearing course may also exhibit some significant tensile stresses after the passing by of a vehicle. The laboratory experiments are presented and the transposition of the phenomenon to a bituminous pavement is discussed on the basis of CESAR-LCPC finite element code.

Online publication: 2004-04-15
Publication type : full_text
Public price (Euros): 0.00