Cracking sensitivity of slag cement concrete

Title: Cracking sensitivity of slag cement concrete
Author(s): A. Darquennes, S. Staquet, B. Espion
Paper category : conference
Book title: 2nd International RILEM Symposium on Advances in Concrete through Science and Engineering
Editor(s): J. Marchand, B. Bissonnette, R. Gagné, M. Jolin and F. Paradis
Print-ISBN: 2-35158-003-6
e-ISBN: 2351580028
Publisher: RILEM Publications SARL
Publication year: 2006
Nb references: 13
Language: English

Abstract: The blast-furnace slag cement concrete presents a lot of advantages but it may also present a higher sensitivity to cracking at early ages than Portland cement concrete. This cracking that may jeopardize the durability is related to the free shrinkage (thermal, autogenous and drying) of the concrete and the restrained conditions. This paper will present and discuss the results of some preliminary laboratory experiments carried out to investigate the cracking sensitivity of slag cement concretes. Various slag cement concretes were studied and compared to reference Portland cement concretes characterized by similar rheological and mechanical performances. The free autogenous and drying shrinkage was recorded during more than one year on cylindrical specimens and the susceptibility of a particular concrete composition to cracking induced by restrained shrinkage was evaluated by ring tests. This study enlights the role of the autogenous deformation at early ages. For slag cement concrete, the magnitude of the autogenous shrinkage was clearly higher and it showed a faster evolution of the kinetics. Furthermore all rings with slag cement concretes exhibited cracking between 15 and 60 days while Portland cement concrete rings resisted to cracking beyond several months. Indeed a more important shrinkage generates a higher tensile stresses rate in concrete. Important deformations growth and slow strength development provide a larger cracking sensitivity at early ages for slag cement concrete.

Online publication: 2006-08-02
Classification: 3.2 Theme 2: From Fresh to Hardened Concrete
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/2351580028.055