Influence of expanded glass aggregate size, aerogel and binding materials volume on the properties of lightweight concrete

Expanded glass aggregate and aerogel is a very lightweight material and has excellent thermal insulating properties, which can be used to produce lightweight thermal insulating cement-based composites. Herewith, two different series of lightweight concrete samples were prepared by using different sizes expanded glass aggregates and silica aerogel. In the first series, the concrete was prepared by using individual and combinations of different sizes of expanded glass aggregates with 787.5 kg/m(3) binding material volume. The second series of concrete samples were prepared by individual and combinations of smaller size expanded glass aggregates with 500 kg/m3 binding material volume to understand the influence of binding materials volume in the lightweight concrete. In addition, a partial amount of expanded glass arrogates was replaced by aerogel particles and aerogel powder to investigate the influence of aerogel particles/powder on the properties of lightweight concrete. The result shows the compressive strength and flowability of lightweight concrete greatly influenced by the aggregate size and its properties. Smaller size aggregate has a higher specific surface area which increases the water demand and greatly influences the flowability of concrete. A higher volume of binding material paste causes the segregations and lightweight aggregates to start floating on the top and influence the uniform distribution of lightweight aggregates in the lightweight concrete. Scanning electron microscopy shows aerogel particle is a very brittle material and has lower adhesive properties with cementitious materials. (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 3rd International Conference on Innovative Technologies for Clean and Sustainable Development.