Influence of different compacting methods on concrete compressive strength

Materia

Oliveira, Alessandro¹  Medeiros-Junior, Ronaldo Alves de²  Lima, Maryangela Geimba de³ 

[1] Department of Civil Engineering, Rio de Janeiro, Brazil;Federal University of Parana, Curitiba, Brazil;Technological Institute of Aeronautics, Sao Jose dos Campos, Brazil

关键词: Concrete;    materials technology;    compressive strength;    durability;    long term data.;   

DOI  :  10.1590/s1517-707620180003.0486

学科分类：工程和技术（综合）

来源: Universidade Federal do Rio de Janeiro * Coordenacao dos Programas de Pos-Graduacao de Engenharia

【 摘 要 】

Adequate compacting is an important stage contributing for the durability and final quality of concrete structures. The two main ways of compacting concrete are: manual and mechanical (immersion vibrator). This paper has the goal of verifying the influence of those two compacting methods on the compressive strength of concrete from long term data. In order to do that, cylindrical test specimens of a same concrete were molded with different compacting methods and the compressive strength was investigated at 1, 3 , 7, 14, 21, 28, 63, 91, 180, 365 and 730 days. Concrete used was casted in plant. Manual compacting was performed using a metallic and cylindrical rod. Mechanical compacting was performed using a rigid immersion vibrator driven by an electric motor. This study confirmed greater compressive strength in test specimens compacted with immersion vibrator, when compared with results in manually compacted test specimens. However, the novelty of this article is that variance analysis test demonstrated that only from 63 days the difference between compressive strengths is significant. Long term data also made it possible to generate a trend equation with good coefficient of determination for estimating the difference between compressive strengths for the two compacting methods investigated over time.

【 授权许可】

CC BY