Determination of standard characteristics of recycled crushed aggregate from crushed sand-lime brick and prospects of its application

Abstract

Introduction. Construction enterprises can adversely affect the environment during the extraction of natural raw materials, as well as during the reconstruction, overhaul, and demolition of buildings. The manufacturing of construction materials, the actual erection, and maintenance of various buildings and structures comprise highly material- and energy-intensive processes characterized by waste generation, which need to be disposed. In developed countries, recycling wastes as a commercial commodity represents the preferable way of recovering concrete, reinforced concrete, and masonry (brick) waste. In this regard, the disposal of construction waste (including waste from sand-lime brick and brickwork) is becoming increasingly important.Aim. In this work, the grain-size distribution, strength, and bulk density of recycled crushed aggregate from crushed sand-lime bricks (open stone mix) and brickwork (containing mortar) were determined and compared, and the prospects of its use as aggregates in the production of general-purpose concrete were identified.Materials and methods. Recycled crushed aggregate from crushed sand-lime bricks (open stone mix) and brickwork (containing mortar) was used for the studies. The recycled crushed aggregate was tested as per GOST 8269.0-97, its characteristics were evaluated as per GOST 8267-93.Results. This work shows the correlation between the bulk density, grain-size distribution, and crushing capacity of recycled crushed aggregate produced by crushing fragments of brickwork (containing mortar) and sand-lime bricks (open stone mix).Conclusions. It is shown that recycled crushed aggregate obtained by crushing fragments of brickwork (containing mortar) and sand-lime bricks (open stone mix) are suitable (along with crushed stone from sedimentary and metamorphic rocks) for use as a coarse aggregate in the production of general-purpose concrete. It is shown that it is necessary to carry out comprehensive experimental work in order to develop a new GOST, which will improve the recycling of sand-lime bricks, as well as structures and products based on them following the end of their operation lifetime, and allow high-quality ready-to-use construction material to be obtained.