sustainability Article Formulation of Compressed Earth Blocks Stabilized by Glass Waste Activated with NaOH Solution Sihem Larbi 1, * , Abdelkrim Khaldi 1 , Walid Maherzi 2, * and Nor-Edine Abriak 2   Citation: Larbi, S.; Khaldi, A.; Maherzi, W.; Abriak, N.-E. Formulation of Compressed Earth Blocks Stabilized by Glass Waste Activated with NaOH Solution. Sustainability 2022, 14, 102. https:// doi.org/10.3390/su14010102 Academic Editor: Giancarlo Renella Received: 13 October 2021 Accepted: 8 December 2021 Published: 23 December 2021 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). 1 Laboratory of Rheology, Transport and Treatment of Complex Fluids (LRTTFC), Hydraulics Department, University of Sciences and Technology of Oran Mohamed Boudiaf (USTO-MB), Oran 31000, Algeria; khaldiakz@yahoo.fr 2 Laboratory of Civil Engineering and Geo-Environment LGCgE, Materials and Process Department, IMT Nord Europe, F-59000 Lille, France; nor-edine.abriak@imt-nord-europe.fr * Correspondence: sihem.larbi@univ-usto.dz (S.L.); walid.maherzi@imt-nord-europe.fr (W.M.) Abstract: Due to the increase in demand for building materials and their high prices in most developing countries, many researchers are trying to recycle waste for use as secondary raw materials. The aim of this study is the optimization of a mixture of compressed earth blocks based on two sediments. These sediments were tested through the Vicat test to determine the proportion of each one and the optimal water content. The mixtures were treated by adding 10% of blast furnace slag and different proportions of dissolved glass in a NaOH solution. The results indicated that the mixture of 70% Oran sediments with 30% Sidi Lakhdar sediments treated with 4% glass waste produced a CEB (compressed earth block) with high compressive strength with low porosity. In addition, formulated CEBs have a very good resistance to water immersion. Keywords: sediments; glass; NaOH concentration; compressed earth blocks; circular economy 1. Introduction Low-cost construction is a modern civil engineering concept that uses locally available materials to obtain the desired strength, performance, and durability [1]. The current construction rate in developing countries is generally insufficient to meet the needs of only a 10% net population increase per year [2]. Therefore, it is necessary to introduce new modern techniques in building construction by using new materials such as compressed earth blocks (CEB), which are a form of a ground construction unit based on the use of local materials [3], stabilized and pressurized to form a soil block [3]. This is an available material that is recyclable as raw materials in cases of improper treatment [4]. The energy needed for their manufacture is also very low. When local sectors are available, the im- pact associated with transportation is negligible. Moisture is the main barrier to using ground bricks [5]. The soil is mixed with an adjuvant, and sometimes Portland cement [6] or hydrated lime is added at a consistent ratio to increase weather resistance [7]. The consumption of CEB in Algeria has increased by around 7.3 million m 3 /year [8]. Sedi- ments raise many problems through the concentration of pollution and the movement of potentially dangerous pollutants [9]. Dredging deposits are considered waste [10] rather than raw materials [11]. Dredged sediments are one of the largest potential waste streams in Algeria, with an annual production of about 10 million m 3 [12]. Inland water bodies in Algeria are estimated to produce 1.9 billion m 3 : 375 Hm 3 /year in Oran and 27 Hm 3 /year in Mostaganem [13]. Recently, several studies have explored the possibility of reusing dredging sediments as alternative materials for different applications: such as a mineral addition to cement [14], as lightweight aggregates [10], raw materials for road construc- tion [15], or as cementation materials [11], geopolymers [16], and bricks and tiles [16,17]. One innovative solution to recovering dredged sediments is the use of environmental binders, also called geopolymer binders or alkaline active binders. Miranda et al. [18] used Sustainability 2022, 14, 102. https://doi.org/10.3390/su14010102 https://www.mdpi.com/journal/sustainability