Insulating Bricks Filled with Cellulose Fibers, Packed in Recycled Plastic and Covered with Mortar Coating

摘要

This article presents a new composite brick made of cellulose fibers packed in a thin, hermetically sealed plastic block made of a set of recycled PET bottles, and coated with a layer of mortar. This brick is made to provide good thermal and acoustic insulation in building walls and possibly in floor slabs. The properties of cellulose fibers, mortar, and PET plastic are presented as well as the manufacturing process used to produce the brick. The physical properties of the proposed brick have been experimentally measured through laboratory tests and they have been numerically evaluated using specific formulae or software simulation. These properties include density, compressive strength, flexural strength, thermal conductivity and sound reduction index. Two thicknesses for the brick are considered in this study: a medium one of 12.5 cm and a large one of 24 cm. Each thickness has allowed obtaining specific properties that have been assessed and compared with other bricks cited in the references. The results of the proposed medium-thickness brick show good resistance to compression, with a more ductile failure mode, as well as a low thermal conductivity and a fair predicted noise reduction index, found using the INSUL 9.0 simulation. The estimated results of the large thickness brick predict a lower yet good compressive strength, with improved insulating properties; in particular a very low thermal conductivity and a good noise reduction index. The results of both the thicknesses have been also compared to the requirements of thermal and acoustic building codes used in many countries. There are several advantages of this brick including cost optimization, sustainment of the environment, and ease of assembly in construction. These advantages have also been discussed to prove their interesting use in the construction of buildings as well as their compliance with the recommendations of thermal and acoustic building codes.