A New Approach for Designing Fluid Concrete with Low Cement Content: Optimization of Packing Density of Aggregates.

Ning Zhang,Shenyou Song,Wen Xu,Wenqiang Zuo

doi:10.3390/ma13184082

Abstract

The current study aims at proposing a novel and simple method for designing fluid concrete such as self-compacting concrete (SCC) with a low cementitious binder content to reduce the carbon footprint. Different testing methods regarding the packing density of aggregate mixtures are performed and compared. The W/C was determined according to the target compression strength. Slump flow spread is carried out to determine the most appropriate superplasticizer (SP) dosage and aggregate volume fractions and proportions in concrete mixtures. Furthermore, hardened performance, including compression strength and drying shrinkage of the fluid concrete, are characterized. Finally, a mix design process of fluid concrete with low cement content was proposed based on the preferred fresh and hardened properties of the concrete mixtures.

Highlights

Since the 1980s, construction projects have placed increasing demands on the workability of concrete
The ever-increasing complexity of the construction elements led to the difficulty of the implementation of the traditional vibrating technology, which further led to serious durability problems due to the lack of the compaction of the fresh concrete
High-range water-reducing agent is required to achieve a high flowability of the interstitial cement paste while maintaining a high content of powders to provide a decent flowability for fresh fluid concrete [1,3,4,5]

Summary

Introduction

Since the 1980s, construction projects have placed increasing demands on the workability of concrete. The ever-increasing complexity of the construction elements led to the difficulty of the implementation of the traditional vibrating technology, which further led to serious durability problems due to the lack of the compaction of the fresh concrete. In order to solve these dilemmas, a flowable concrete, which was later named self-compacting concrete (SCC), was designed by Okamura et al [1,2]. The idea behind this novel type concrete is to reduce the size and the amount of the coarse aggregates and to increase the powder and paste content in the mixture. High-range water-reducing agent is required to achieve a high flowability of the interstitial cement paste while maintaining a high content of powders to provide a decent flowability for fresh fluid concrete [1,3,4,5]

Methods

Results

Conclusion