Permeability testing of radiation shielding concrete manufactured at industrial scale

Wojciech Kubissa,Mariusz Dąbrowski,Michał A Glinicki

doi:10.1617/s11527-018-1213-0

Abstract

The effect of the composition of industrial concrete designed for radiation shielding structures on the air permeability and the diffusion of moisture was studied. The mix design for heavyweight concrete of bulk density 3168–3317 kg/m3 was developed using barite and magnetite aggregate and cements blended with fly ash and blastfurnace slag. Structural elements, like columns of a height of 4 m and massive blocks made of mixtures with different cements were manufactured using ready mixed concrete pumped into the formwork. Core specimens were taken from the elements at different locations. The air permeability index was tested using Autoclam device. Evaluation of the quality of concrete on the basis of API results varied from “very good” to “good”. The moisture distribution inside concrete specimens was equilibrated to RH = 60 ± 5%. Observation of RH changes allowed to determine the moisture diffusion coefficient. Significant differences of the permeability and moisture diffusion coefficient depending on the location of the core specimens drilling and mix design of concrete were found. The D coefficient provided a good reflection of the different quality of heavyweight concrete in structural elements.

Highlights

The criteria for selection of ingredients and concrete mix design for radiation shielding structures include both mechanical and physical properties, the shielding against ionizing radiation, and the impermeability to liquids and gases [1, 2]
The evolution of relative humidity (RH) distribution in the specimen B during concrete drying and RH stabilization period is shown in Figs. 2 and 3
During the moisture stabilization period it can be observed that the rate of RH change in different specimen layers is well correlated with RH gradients

Summary

Introduction

The criteria for selection of ingredients and concrete mix design for radiation shielding structures include both mechanical and physical properties, the shielding against ionizing radiation, and the impermeability to liquids and gases [1, 2]. A low permeability concrete can prevent the penetration of harmful substances to the inside of the structure. This reduces the risk of corrosion of the reinforcement or the destruction of the concrete. It is important for example in the storage pools for spent fuel [3].

Results

Discussion

Conclusion