Effects of expansive additive on cement composite properties

Construmat 2018

Gregorova, V.^1 ; Stefunkova, Z.^1 ; Ledererova, M.^1

Department of Material Engineering, Faculty of Civil Engineering, Slovak University of Technology in Bratislava, Radlinskeho 11, Bratislava

810 05, Slovakia^1

关键词: Cement composite;    Cement mortars;    Environmental conditions;    Expansive additives;    Expansive cement;    Fresh concrete;    Physical process;    Synthetic gypsum;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/385/1/012015/pdf
DOI  :  10.1088/1757-899X/385/1/012015

来源: IOP

【 摘 要 】

Shrinkage is a due to chemical and physical processes in concrete. The results of these are volume changes that may cause cracking, deformation, decrease in strength and especially durability of a construction. The amount of water in concrete, the fine particles content, the dimension of construction, the method of curing of the fresh concrete and environmental conditions (temperature, humidity) are some factors influencing the shrinkage of concrete. This article deals with reduction the shrinkage of cement composites by addition of expansive cement Denka CSA and synthetic gypsum. The additives were used at a dosage of 10% of the original weight of cement. The obtained results showed different impact of these additives to the volume changes and the compressive strength of cement composites. The Denka CSA additive had a positive effect to monitored properties of cement mortars. It caused the lowest shrinkage; slight increasing of long-term compressive strength and decreasing of bulk densities after 2, 28 and 90 days of hardening.