Degradation of concrete subjected to simultaneous attack of freeze-thaw and sustained flexural load
Title: Degradation of concrete subjected to simultaneous attack of freeze-thaw and sustained flexural load
Author(s): R. Mu, W. Sun, C. Miao, J.P. Forth
Paper category : conference
Book title: International Conference on Microstructure Related Durability of Cementitious Composites
Editor(s): W. Sun, K. van Breugel, C. Miao, G. Ye and H. Chen
Publisher: RILEM Publications
Publication year: 2008
Pages: 593 - 600
Total Pages: 8
Nb references: 16
Abstract: In this paper a new method is proposed to assess the degree of degradation of concrete subjected to the simultaneous action of several deterioration factors. In the method, a coefficient (the damage index) is defined by which all deteriorations involved can be taken into account. The deterioration of concrete under the simultaneous attack of freeze-thaw cycling and sustained external flexural load is experimentally tested and then the the degradation of the concrete under this complex deterioration is analysed using the new method. In the experiment, relative dynamic modulus of elasticity and mass loss are measured.
The experimental results show that the drop in relative dynamic modulus of elasticity of the concrete specimens dominants the failure of concrete whilst the mass loss mainly causes a considerable degradation at the initial stage. In the curve of the damage index corresponding to the concrete tested, the contribution of mass loss and the drop in relative dynamic modulus of elasticity to the degradation of concrete are clearly reflected with an obvious increase during the initial stage, followed by a slow increasing period and then finally a sharp increase in damage index. Also it is observed that the mass loss is not sensitive to external load. The criterion for mass loss suggested in the standards is quite easy to be satisfied and a more rigorous criterion should be proposed. For multi-factor attack, the interaction between the relevant factors plays an important role, which leads to the acceleration of the deterioration of concrete.
Online publication: 2009-06-09
Publication type : full_text
Public price (Euros): 0.00