The Utilization of Recycled Masonry Aggregate and Recycled EPS for Concrete Blocks for Mortarless Masonry

Abstract

The main aim of this paper is to carry out the environmentally based enhancement of a concrete mixture containing recycled materials whilst considering natural resource consumption as well as mechanical and thermal property levels. The developed concrete is intended to be used in mortarless masonry wall structures. Ten concrete mixtures with different types and replacement rates of recycled masonry aggregate and recycled expanded polystyrene were prepared, and their mechanical and thermal properties were experimentally investigated. It was found that the use of recycled masonry aggregate led to better thermal properties while maintaining sufficient mechanical properties. On the contrary, the addition of recycled expanded polystyrene did not significantly affect the thermal properties of concrete, but the mechanical properties considerably declined. For this reason, the recycled masonry aggregate is suitable to use as an aggregate for concrete masonry blocks for wall structures.

Sustainable Masonry Made from Recycled Aggregates: LCA Case Study

“…The utilization of recycled aggregate (RA) from construction and demolition waste (CDW) as a partial or full replacement of natural aggregate (NA) in concrete mixtures mostly negatively influences its mechanical and durability properties. However, RA has a positive impact on thermal properties [2,3]. The RA from waste concrete (RCA) is mostly used for constructing base layers in road structures and RA from waste masonry (RMA), as backfill layers or as layers to make landfills safe.…”

“…There have been many studies published in which concrete including different recycled materials is used for structural elements, for instance, RCA [12][13][14][15][16][17][18], RMA [2,[19][20][21][22][23][24][25][26][27], glass waste [28][29][30][31], crumb rubber waste [32][33][34], ceramic and tile industry waste [35], marble waste [36,37], plastic waste [38], and concrete slurry waste [39,40]. The use of RA as a partial or full replacement of aggregate in structural concrete was examined for manufacturing precast prestressed beams [41], paving with precast concrete [23], paving blocks or hollow tiles [25], concrete masonry blocks for indoor applications [19,20], or concrete wall blocks for mortarless masonry [2]. The utilization of RA for reinforced concrete structural elements is limited due to the inferior durability properties of RAC [42,43].…”

“…This paper presents a comparison of the four wall systems with the same utility characteristics, as well an environmental evaluation of the systems using the LCA method. The following constructions were compared: (1) Reusable masonry blocks made of RMAC with full replacement of NA by RMA; (2) reusable masonry blocks made of RCAC with full replacement of natural gravel and partial replacement of natural sand by RCA; (3) reusable masonry blocks made of NAC with only NA; (4) conventional Sustainability 2020, 12, 1581 3 of 21 concrete wall system with only NA. These constructions were compared in four scenarios with the different time scales of use and other assumptions.…”

Comparing Compressive Strengths of Layered and Random Placement of Expanded Polystyrene Wastes in Quarry Dust Blocks

“…Proponents of EPS encourage its use as it results in overall cost reduction by 25 % and construction time by 50%, therefore ideal building material for the poor. Another advantage of EPS is that it results in thermal insulation of houses [2]. On the contrary, EPS use in construction, leaves behind a trail of wastes and hence the need to recycle them in this era of sustainable development.…”

“…[12] considered using EPS beads reinforced with polyamide-66 in coming up with lightweight concrete. A study by [2] compared densities of concrete made of recycled EPS and recycled concrete. As [7] and manufacturers worldwide advocate and promote the use of EPS, there is need for in-depth study on EPS so as to give more information that will guide decision makers at the county and national levels in Kenya.…”