Ash-related issues during biomass combustion: Alkali-induced slagging, silicate melt-induced slagging (ash fusion), agglomeration, corrosion, ash utilization, and related countermeasures

Recent advances in understanding the role of supplementary cementitious materials in concrete

Degree of hydration and gel/space ratio of high-volume fly ash/cement systems

Aerogel is a kind of synthetic porous material, in which the liquid component of the gel is replaced with a gas. Aerogel has specific acoustic properties and remarkably lower thermal conductivity (≈0.013 W/m K) than the other commercial insulating materials. It also has superior physical and chemical characteristics like the translucent structure. Therefore, it is considered as one of the most promising thermal insulating materials for building applications. Besides its applications in residential and industrial buildings, aerogel has a great deal of application areas such as spacecrafts, skyscrapers, automobiles, electronic devices, clothing etc. Although current cost of aerogel still remains higher compared to the conventional insulation materials, intensive efforts are made to reduce its manufacturing cost and hence enable it to become widespread all over the world. In this study, a comprehensive review on aerogel and its utilization in buildings are presented. Thermal insulation materials based on aerogel are illustrated with various applications. Economic analysis and future potential of aerogel are also considered in the study.

Toward aerogel based thermal superinsulation in buildings: A comprehensive review

This paper presents a laboratory investigation on optimum level of ground granulated blast-furnace slag (GGBS) on the compressive strength of concrete. GGBS was added according to the partial replacement method in all mixtures. A total of 32 mixtures were prepared in four groups according to their binder content. Eight mixes were prepared as control mixtures with 175, 210, 245 and 280 kg/m3 cement content in order to calculate the Bolomey and Feret coefficients (KB, KF). For each group 175, 210, 245 and 280 kg/m3 dosages were determined as initial dosages, which were obtained by removing 30 percent of the cement content of control concretes with 250, 300, 350, and 400 kg/m3 dosages. Test concretes were obtained by adding GGBS to concretes in an amount equivalent to approximately 0%, 15%, 30%, 50%, 70%, 90% and 110% of cement contents of control concretes with 250, 300, 350 and 400 kg/m3 dosages. All specimens were moist cured for 7, 14, 28, 63, 119, 180 and 365 days before compressive strength testing. The test results proved that the compressive strength of concrete mixtures containing GGBS increases as the amount of GGBS increase. After an optimum point, at around 55% of the total binder content, the addition of GGBS does not improve the compressive strength. This can be explained by the presence of unreacted GGBS, acting as a filler material in the paste.

An experimental study on optimum usage of GGBS for the compressive strength of concrete

Behaviour of lightweight expanded polystyrene concrete containing silica fume

Properties of lightweight expanded polystyrene aggregate concretes containing fly ash

Efficiency of GGBS in concrete

The aim of this study is to investigate the effect of polystyrene aggregate size on strength and moisture migration characteristics of lightweight concrete. The present study covers the use of expanded polystyrene (EPS) and un-expanded polystyrene (UEPS) beads as lightweight aggregate in concretes that contain fly ash as a supplementary cementitious material. Lightweight concrete with wide range of concrete densities (1000–1900 kg/m3) were studied mainly for compressive strength, split tensile strength, moisture migration and absorption. The results indicate that for comparable aggregate size and concrete density, concrete with UEPS aggregate exhibited 70% higher compressive strength than EPS aggregate. EPS aggregate concrete with small EPS aggregates showed higher compressive strength and the increase in compressive strength was more pronounced in low density concrete when compared with high density concrete. The UEPS aggregate concrete exhibited brittle failure similar to normal weight concrete (NWC), whereas, gradual failure was observed in EPS concrete. Moreover, the moisture migration and absorption results indicate that the EPS concrete containing bigger size and higher volumes of EPS aggregate show higher moisture migration and absorption.

K. Ganesh Babu

Papers

Behaviour of lightweight expanded polystyrene concrete containing silica fume

Properties of lightweight expanded polystyrene aggregate concretes containing fly ash

Efficiency of GGBS in concrete

Effect of polystyrene aggregate size on strength and moisture migration characteristics of lightweight concrete

Quantification of hydrated cement products of blended cements in low and medium strength concrete using TG and DTA technique