The aim of this study is to find a way to reuse the huge amounts of glass wastes in construction industry, by making new products at a lower price and also to reduce the glass wastes. In this research several types of ecological plastering mortars have been studied from a physical and mechanical point of view when natural aggregates were replaced by waste glass. The research also aims to study the impact which glass waste has on the hydration processes and the dimension of pores of the plastering mortars using innovative methods, such as optical microscopy and nuclear magnetic resonance. The objective of this study is to support the sustainable development policy, which requires mainly the development of eco-friendly constructions, based on two major goals: construction of buildings based on a sustainable design and constructions achieving energy performance

The current context regarding the management of waste obtained from the construction industry, according to European Union laws and directives, requires the imposition of an integrated waste management system. The main objective of this study was to integrate and reuse old plaster waste as a substitute for aggregates in significant proportions in mortar composition and analyzing the impact on the physical and mechanical characteristics of mortar in fresh state and in hardened state. Over periods of 7, 14, and 28 days, the experimental program studied three types of plastering mortars: a standard recipe (without waste) and another two proposed recipes, in which construction waste was re-used as a substitute for aggregates in proportions of 10% and 15%. Results obtained on the fresh properties of the proposed plastering mortars (apparent density, consistency, and segregation trend) indicated a variation (increase/decrease) of 1% to 2.5% compared with the standard recipe. Mechanical strengths showed decreased values; that is, the compressive strength decreased by 11.09% and the flexural strength decreased by 22% when waste replaced aggregates in a proportion of 15%. The results of the experimental program identified the potential of waste plaster, which can replace up to 15% of the aggregates in plaster mortars, which still guarantees their successful use in practice. To reduce the influence of the use of waste on the mechanical strengths, we propose to conduct further investigations (nuclear magnetic resonance, electronic microscopy, and X-ray diffraction) on these mortars reinforced with different types of fibers. The large amount of waste resulting from the rehabilitation of damaged building facades and the fact that there are currently no experimental studies on the reuse of waste from old plaster mortars were the main reasons for the present study examining the possibility of their use in the production of new building materials.

The rising concern for the environment and the need for a sustainable economic model has stimulated experimentation in the field of construction materials, notably in replacing certain components from cementitious materials with construction and demolition waste. The main objective of this study is to replace a significant proportion of natural aggregates with glass waste, in the composition of plastering mortars, and to observe the evolution of physical–mechanical characteristics in the fresh state: apparent density, consistency, and segregation tendency, and in the hardened state: apparent density, flexural strength, compression strength, and adhesion to the substrate, across time, at 3, 7, 14, and 28 days. SEM and EDX tests were also performed to observe the microscopical characteristics. The experimental program studied four types of plastering mortars: the reference mortar—CS IV, and three mortars in which aggregates have been replaced with glass waste in the following proportions, by mass: 15%, 30%, and 45%. Results obtained on fresh properties (apparent density and consistency) indicate a decrease in values as the percentage of glass increases, with the exception of the mortar with 30% aggregated glass replacement. The flexural strength and the compressive strength were improved by replacing 30% of the aggregates with glass waste and were not significantly impacted by a replacement of 15%. Mechanical properties decreased at a replacement level of 45%. All glass aggregate mortars had lower adhesion strength to the brick substrate than the reference mortar by up to 70%. SEM and EDX analyses showed the morphology of the studied mortars and the processes taking place to increase mechanical strength. Further research directions are proposed, including studying the glass particles, the occurrence of alkali–silica reactions, durability, and improvement of adhesion to the substrate, for progressing towards the most viable, locally sourced, waste-containing plastering mortar.

The current framework for managing construction waste, guided by European Union regulations, calls for an integrated waste management system. However, the reuse of old plaster waste, particularly from deteriorated facades, remains underexplored. This study investigates the potential of repurposing old plaster waste as a substitute for aggregates and cement in mortars, with the aim of promoting environmental sustainability and resource efficiency. Three mortar mixes were analyzed: a control mix, a mix with 45% waste replacing aggregates, and a mix with 10% waste replacing cement. Results show that replacing 45% of aggregates with plaster waste led to a 30% reduction in flexural strength, while the 10% cement replacement increased flexural strength by 6%. Compressive strength dropped by 27% and 38% for cement and aggregate replacements, respectively. Despite these reductions, the waste replacement remained within acceptable limits for structural integrity. Further microscopic analysis revealed that the incomplete integration of portlandite particles from the waste contributed to non-uniform bonding and crystal formation, weakening the mortar’s structure. This research demonstrates the feasibility of reusing old plaster waste, offering a novel approach to reducing construction waste and promoting a circular economy. It contributes to filling the knowledge gap on the reuse of plaster mortars while aligning with sustainable construction goals.