Understanding the effect of porosity on the mechanical and thermal performance of glass foam lightweight aggregates and the influence of production factors

Effect of different expanded aggregates on durability-related characteristics of lightweight aggregate concrete

“…Lightweight aggregate concrete (LWAC) is a versatile lightweight material that satisfies both thermal and mechanical performance requirements, i.e. relatively low thermal conductivity and appropriate compressive strength, considering its material density [11,12]. Highly porous natural or synthetic lightweight aggregates are used to produce LWAC; it is their presence which is the main reason for the low bulk density [13].…”

High-speed synchrotron X-ray imaging of glass foaming and thermal conductivity simulation

“…This mechanism was recently observed in foaming of metals [35]. Recently it was observed in glass foam light-weight aggregates that the porosity increases without any change in pore size before reaching a porosity around 60 % [11]. The higher porosities at the later stage of the heating is thereafter caused by an increase in the pore size.…”

“…These data clearly show that the gas phase composition is a crucial parameter for simulating λ at high porosities. Some reported values are higher than the simulated values, which is very likely linked to a higher solid contribution due to crystal residues from foaming agents in the solid phase [6] or a difference in the pore structure, e.g., in pore size [9][10][11]. Both differences increase the contribution of the solid phase to the effective thermal conductivity.…”

“…As the porosity increases, the contributions of each phase and pore structure become increasingly important. The thermal conductivity of highly porous glass foams is, therefore, highly dependent on the contribution of the glass phase [5] and its susceptibility to crystallization or its crystal content from foaming residues [6,7], the composition of the gaseous phase in the pores [8], the porosity type (open or closed) and the pore structure (pore size and the thickness of the struts and walls) [2,3,7,[9][10][11].…”

Experimental Evaluation of an Innovative Non-Metallic Flat Plate Solar Collector

“…In the case of the proposed collector, the block has a plate shape, and its thickness is determined by ensuring sufficient thermal resistance of the block and sufficient rigidity of the structure (frame function). Due to the value of the coefficient of thermal conductivity λ, which in the case of foam glass is 0.038 to 0.048 W.m −1 .K −1 [41], it was possible to consider the total thickness of the insulating part of the block of 60 mm. The foam glass block also contains openings for connection fittings and tear-shaped recesses serving as a distribution or the collecting section of the flow channels as seen in Figure 2.…”