Evaluation of the effect of concrete compositional changes and the use of ethyl-alcohol and biodegradable-oil-based release agents on the final surface appearance of self-compacting concrete precast elements

被引：10
作者：
da Silva, W. R. L. [1 ]
Lucena, D. S. [2 ]
Stemberk, P. [3 ]
Prudencio, L. R., Jr. [4 ]
机构：
[1] Czech Tech Univ, Fac Civil Engn, Dept Mech, Prague 16629 6, Czech Republic
[2] Pontificia Univ Catolica Parana, Fac Mechatron Engn, Curitiba, Parana, Brazil
[3] Czech Tech Univ, Fac Civil Engn, Dept Concrete & Masonry Struct, Prague 16629 6, Czech Republic
[4] Univ Fed Santa Catarina, Dept Civil Engn, BR-88040900 Florianopolis, SC, Brazil
来源：
CONSTRUCTION AND BUILDING MATERIALS | 2014年 / 52卷
关键词：
Bugholes; Image analysis; Precast concrete; Release agent; Self-compacting concrete; IMAGE-ANALYSIS;
D O I：
10.1016/j.conbuildmat.2013.10.102
中图分类号：
TU [建筑科学];
学科分类号：
0813 ;
摘要：
his paper investigates bughole minimization techniques in self-compacting concrete in a precast concrete plant in Brazil. Specifically, the objective of this study was to improve the final surface appearance of self-compacting concrete precast elements with respect to the presence of bugholes. Bugholes are imperfections that appear on a concrete surface after demoulding. The experimental study was based on the modification of concrete composition and the use of two types of release agents. In particular, ethyl-alcohol and biodegradable-oil-based admixtures were applied on laminated plywood formwork. By using a specific image analysis method, the concrete surface was analyzed using digital images taken from concrete board plates with dimensions of 1.00 x 0.30 x 0.08 m. The results indicate that a reduction in the concrete shear stress ratio contributed to reduce the percentage of bugholes, whereas no significant difference in the concrete surface appearance was observed as a function of the investigated release agents. (C) 2013 Elsevier Ltd. All rights reserved.
引用
收藏
页码：202 / 208
页数：7
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