Experimental study of axial compression of reinforced concrete columns made by environment‐friendly post‐filling coarse aggregate process

Abstract

The increase of coarse aggregate content decreases the shrinkage of concrete, decreases the cost of concrete production as well as reduces the carbon dioxide emission to the environment. In this study, the mixture proportions of PFCC (post‐filling coarse aggregate concrete) for C40, C50, and C60 were designed and the comprehensive performances of workability, compressive strength and elastic modulus were conducted experimentally. Then, 15 reinforced concrete columns made by PFCC with different concrete grades and post filling rates (PFR) were designed and tested. The failure mode, load‐deflection curve, load‐strain curve and load bearing capacity were analyzed and elaborated. Results showed that, compared with the conventional concrete, the compressive strength and elastic modulus of the post filling coarse aggregate concrete were improved, which reached the highest when the post filling rate is 20%. At the same time, the load bearing capacity of column specimen increased first and then decreased as the post filling rate increased, with the transition point being at 10% post filling rate. This study provides reference and research data for technical regulations and design specifications of structural members made of post filling coarse aggregate concrete.

Seismic performance of reinforced concrete beam‐column joint made of post‐filling coarse aggregate concrete

“…Its flexural performance increases first and then decreases with the increase of post‐filling ratio, reaching the best at 20%. Jia et al 24 also studied the effect of volume replacement ratio, strength grade of concrete, shear span ratio, volume‐stirrup ratio on the shear performance and results shows that 25 the post‐filling aggregate process can reduce the porosity and increase the concrete strength by reducing the effective water binder ratio and increasing the volume fraction of aggregate, among which the effect of increasing the volume fraction of aggregate is more significant. When the concrete strength grade is certain, the ultimate bearing shear force of the beam as a whole increases first and then decreases with the increase of the post‐filling ratio, reaching the peak at 15%.…”

“…Cao et al 25,26 studied the axial and eccentric compression performance of post-filling coarse aggregate concrete columns. Test results show that the ultimate bearing capacity of concrete columns with small eccentric compression can be improved by the post-filling aggregate.…”

“…Although the basic properties, flexural and shear properties of beams as well as axial compression and eccentric compression of columns specimens have been investigated, 1,[22][23][24][25][26] the seismic behavior of beam-column joint made of post-filling coarse aggregate concrete has not been reported. It is crucial to study and understand the seismic behavior of post filling coarse aggregate to facilitate its application in engineering.…”

Shear Behavior of Reinforced Post-Filling Coarse Aggregate Concrete Beams Produced by Creative Construction Process

“…The technology of post-filling coarse aggregate concrete could reduce cement production and decrease carbon emissions. Furthermore, the compressive strength, elastic modulus and load-carrying capacity of columns of post-filling coarse aggregate concrete were also found to be improved [5,21,22]. The post-filling coarse aggregate ratio (PFR) is the volume fraction of the coarse aggregate in the total volume of the post-filling coarse aggregate concrete.…”