Comparison of lightweight aggregate and foamed concrete with the same density level using image-based characterizations. (30th June 2019)

• Record Type: Journal Article
• Authors: Chung, Sang-Yeop; Abd Elrahman, Mohamed; Kim, Ji-Su; Han, Tong-Seok; Stephan, Dietmar; Sikora, Pawel
• Is Part Of: Construction & building materials. Volume 211(2019)
• Page Start: 988
• Page End: 999
• Publication Date: 2019-06-30
• Subjects: Lightweight aggregate concrete -- Foamed concrete -- X-ray μ-CT -- SEM -- Density -- Compressive strength -- Thermal conductivity; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2019.03.270
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The characteristics and properties of lightweight aggregate concrete and foamed concrete with the same density levels were investigated based on image analysis. SEM images confirmed that the solid structures of the matrix in foamed concrete are relatively denser than that of lightweight aggregate concrete. The micro-CT images demonstrated that foamed concrete has larger porosity than lightweight aggregate concrete when the material density is similar. The proper use of lightweight aggregate concrete can be more beneficial in terms of having a material with better mechanical performance by minimizing the loss of the insulation effect. Abstract: Lightweight concrete is a special type of concrete with low density and advanced insulation, mainly produced using lightweight aggregates or a cellular matrix. Concrete material made of lightweight aggregates is called lightweight aggregate concrete, while material made from a cellular matrix is generally called foamed concrete because of the pores introduced by a foaming agent. Both lightweight concrete types have different characteristics due to their different compositions. In this study, the material properties and characteristics of these lightweight concretes were investigated and compared. A series of foamed and lightweight aggregate concrete specimens with the same density level were produced, with their mechanical and thermal properties being evaluated using sensitive measurement tools. X-ray micro-computed tomography ( μ -CT) and scanning electron microscopy (SEM) were used to characterize each material, using image-based techniques. The results brought to light the details of each lightweight concrete, at the microstructural level, in regard to their material properties and showed that the properly designed lightweight aggregate concrete can be more beneficial in mechanical performance by minimizing the loss of the insulation.