Shrinkage and cracking behavior of high performance concrete containing a MgO-CaO composed expansive agent

Title: Shrinkage and cracking behavior of high performance concrete containing a MgO-CaO composed expansive agent
Author(s): Changwen Miao, Jiaping Liu, Fei Guo, Shouzhi Zhang, Yujiang Wang
Paper category : conference
Book title: International RILEM Conference on Use of Superabsorbent Polymers and Other New Additives in Concrete
Editor(s): O.M. Jensen, M.T. Hasholt and S. Laustsen
Print-ISBN: 978-2-35158-104-9
e-ISBN: 978-2-35158-105-6
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 179 - 191
Total Pages: 13
Nb references: 11
Language: English

Abstract: This paper gives a comprehensive investigation on the effects of a new type of MgO-CaO composite expansive agent (MC) on the shrinkage and associated cracking behaviour of hardened high performance concrete, including length change under saturated condition, sealed condition and drying condition, and cracking under single-ring restraint, dual-ring restraint and deformation-controlled Temperature Stress Testing Machine restraint. Experimental results showed that the addition of 8% MC not only built effective expansion in HPC whatever under saturated condition or under sealed condition, but also substantially reduced its drying shrinkage. The measured shrinkage reduction was up to 65% at the age of 120d of drying. It was also found that the addition of MC could effectively improve the shrinkage cracking resistance of HPC even under drying condition. The experimental results of Temperature Stress Testing Machine showed that the expansion of MC could build effective pre-compression and partially compensate the tensile stress during the course of temperature descending, which lowered the cracking temperature of HPC more than 10°C.

Online publication: 2010-10-04
Publication type : full_text
Public price (Euros): 0.00