Impact of recycled aggregate brick on the physical-mechanical and environmental characteristics of cement treated bases

Recycled aggregate brick (RAB) constitutes a significant waste stream in developed countries, originating from brick manufacturing and demolition processes. This paper investigates the potential utilization of various sizes of RAB as replacements for natural aggregate (NA) in cement-treated bases (CTB), along with an assessment of their mechanical and environmental properties. The study includes a life cycle analysis to evaluate the environmental impacts of different CTB formulations. The novelty of this study lies in the environmental evaluation of four types of CTB, including natural, recycled, and mixed CTB. The physical and mechanical properties of the recycled brick and natural materials are characterized and compared. Results indicate that recycled brick aggregates, when combined with a cement mixture, can be used as a base and sub-base layer with good mechanical performance. Moreover, environmental analyses demonstrate that recycled aggregate generates fewer impacts than natural aggregates. Consequently, this study suggests that the utilization of recycled aggregates brick in CTB offers a sustainable waste management solution while simultaneously contributing to the reduction of environmental impacts associated with construction activities

Rheological and mechanical performance evaluation of high performance mortar based natural pozzolan

This paper presents an experimental study on the rheological and mechanical properties of High Performance Mortar (HPM) based on natural pozzolan (NP). The specific surface BET of NP was 370 m²/kg used with different contents by weight of cement (5, 10, 15 and 20%). Two (w/b) water-binder ratios (0.35and 0.40) were used, the dosage of Superplasticizer (Sp) was kept constant (0.32 by weight of cement). The experimental results show that rheological properties of HPM increased with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both yield stress and plastic viscosity of mixtures.The mechanical characteristics were improved with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both compressive strength. The optimal percentage substitution was 15% of NP, reducing CO2 emission by 20% for each cubic meter of mortar production

Rheological and mechanical performance evaluation of high performance mortar based natural pozzolan

This paper presents an experimental study on the rheological and mechanical properties of High Performance Mortar (HPM) based on natural pozzolan (NP). The specific surface BET of NP was 370 m²/kg used with different contents by weight of cement (5, 10, 15 and 20%). Two (w/b) water-binder ratios (0.35and 0.40) were used, the dosage of Superplasticizer (Sp) was kept constant (0.32 by weight of cement). The experimental results show that rheological properties of HPM increased with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both yield stress and plastic viscosity of mixtures.The mechanical characteristics were improved with increasing NP content when w/b kept constant, but the increasing of (w/b) ratio led to decrease of both compressive strength. The optimal percentage substitution was 15% of NP, reducing CO2 emission by 20% for each cubic meter of mortar production

Impact of recycled aggregate brick on the physical-mechanical and environmental characteristics of cement treated bases

Recycled aggregate brick (RAB) constitutes a significant waste stream in developed countries, originating from brick manufacturing and demolition processes. This paper investigates the potential utilization of various sizes of RAB as replacements for natural aggregate (NA) in cement-treated bases (CTB), along with an assessment of their mechanical and environmental properties. The study includes a life cycle analysis to evaluate the environmental impacts of different CTB formulations. The novelty of this study lies in the environmental evaluation of four types of CTB, including natural, recycled, and mixed CTB. The physical and mechanical properties of the recycled brick and natural materials are characterized and compared. Results indicate that recycled brick aggregates, when combined with a cement mixture, can be used as a base and sub-base layer with good mechanical performance. Moreover, environmental analyses demonstrate that recycled aggregate generates fewer impacts than natural aggregates. Consequently, this study suggests that the utilization of recycled aggregates brick in CTB offers a sustainable waste management solution while simultaneously contributing to the reduction of environmental impacts associated with construction activities

Effect of the fineness of mineral additions on the behavior of low impact environment self-compacting mortars

The aim of this experimental work is to analyze the effect of mineral additions fineness on the hydration of self-compacting mortars, as well as their behavior in the fresh and hardened states. To do this, cement was partially replaced with a fixed rate of 20% for natural pozzolan and 30% for slag. The additions were ground to three different fineness. The results showed that the use of slag is favourable to the formulation of self-compacting mortars, the workability has been considerably improved, the increase in its fineness, meanwhile, reduces the dosage of superplasticizer up to 46%. For the pozzolan, on the other hand, not only was the workability reduced, but the increase in fineness implies an additional demand for superplasticizer up to 16%. Mortars based on additions release less heat, nevertheless, this reduction is accompanied by a drop in compressive strength at a young age. However, the increase in fineness lets to accelerate the initial hydration, inducing additional strength, and to generate heat comparable to that of the reference mortar. Nonetheless, in the case of excessive grinding, the heat release must be taken into account in order to avoid the thermal cracking