M. TEBBAL Nadia

The disposal of sewage sludge from wastewater treatment plants presents significant environmental and economic challenges. Thermal treatment of sewage sludge results in sewage sludge ash (SSA), a by-product with pozzolanic and cementitious properties, offering a potential solution for sustainable construction materials. This review explores the valorization of SSA as a partial replacement for cement and aggregates in concrete and mortar production, aiming to enhance sustainability while reducing the environmental footprint of the construction industry. A critical analysis of SSA’s chemical composition, mineralogical phases, and physical characteristics highlights its compatibility with cementitious materials. Studies indicate that incorporating SSA can improve specific mechanical and durability properties, such as sulfate resistance, water absorption, and long-term strength. However, challenges related to SSA variability, heavy metal content, and its impact on fresh and hardened properties require
further investigation. This review discusses existing research on SSA’s integration into concrete and mortar, outlines the limitations of current applications, and identifies future research needs. The findings support SSA as a viable alternative material in construction, promoting circular economy principles and sustainable waste management.

Nanomaterials are transforming the field of civil engineering by significantly enhancing the performance and durability of construction materials and infrastructure. This research explores the innovative applications of nanotechnology in civil engineering, focusing on how nanomaterials improve the properties of traditional materials like concrete, steel, and asphalt. The study examines the impact of nanoparticles, such as carbon nanotubes, nano-silica, and nano-titanium dioxide, in increasing the mechanical strength, durability, and self-healing capabilities of these materials.
Moreover, the research delves into the environmental benefits of using nanomaterials, including their potential to reduce the carbon footprint of construction processes and extend the lifespan of infrastructure. The incorporation of nanomaterials also offers new functionalities, such as enhanced resistance to corrosion, improved thermal insulation, and the ability to monitor structural health in real-time through embedded sensors.
While the advantages of nanomaterials in civil engineering are significant, the study also addresses the challenges, including the high cost of production, potential environmental risks, and the need for standardized testing methods. As the field continues to evolve, this research aims to provide a comprehensive overview of the current state of nanomaterials in civil engineering, highlighting their potential to revolutionize the construction industry and contribute to more sustainable and resilient infrastructure.

Valorization of glass waste in brick manufacturing , 5th International Conference on Scientific and Academic Research on 23-24 December in 2024 at Konya/Turkey

In order to create a geopolymer or alkali activated material similar to cementitious materials for chemical
and physical study as well as mechanical behavior, the majority of prior research on the terms alkaline and
thermal activation was applied in the presence of cement as the main constituent and mixed with industrial
waste such as (red brick, slag, ceramic and glass…etc). The solubility of aluminates-silicates can be
facilitated by chemical solutions, such as KOH, NaOH and Na2SiO3 or Na2CO3, at varying concentrations.
The effectiveness of these methods depends on the nature of the system (CaO-SiO2-Al2O3) in mineral
residues. Additionally, there is the thermal method, which involves hardening the material at a temperature
difference of 20°C to 80°C for a period of 24 to 48 hours. Studies and researchers have found that all these
methods to protect the environment and give perfect solutions to recycler the maximum of the minerals waste
for making the alternative binders.

This review delves into the intersection of self-healing materials and sewage sludge ash (SSA) as a transformative approach in sustainable construction. Self-healing materials offer the ability to autonomously repair cracks, significantly enhancing structural lifespan and reducing maintenance efforts. Meanwhile, SSA, a by-product of wastewater treatment processes, provides an eco-friendly alternative to conventional cement and fine aggregates, addressing environmental concerns by recycling waste and reducing carbon emissions.
Through a comprehensive evaluation of recent research, this review explores the combined application of these innovative materials, assessing their impact on mechanical properties, durability, and environmental sustainability. Key findings highlight the potential of SSA to improve the microstructure and performance of self-healing concrete, while the integration of advanced repair mechanisms ensures prolonged functionality and resilience under environmental stressors.
The review also identifies existing challenges, including the optimization of SSA processing methods and the compatibility of self-healing technologies with alternative binders. By summarizing state-of-the-art developments and proposing future research directions, this study underscores the potential of combining SSA and self-healing materials to revolutionize construction practices, promoting the development of resilient, low-carbon infrastructure.

This review delves into the intersection of self-healing materials and sewage sludge ash (SSA) as a transformative approach in sustainable construction. Self-healing materials offer the ability to autonomously repair cracks, significantly enhancing structural lifespan and reducing maintenance efforts. Meanwhile, SSA, a by-product of wastewater treatment processes, provides an eco-friendly alternative to conventional cement and fine aggregates, addressing environmental concerns by recycling waste and reducing carbon emissions.
Through a comprehensive evaluation of recent research, this review explores the combined application of these innovative materials, assessing their impact on mechanical properties, durability, and environmental sustainability. Key findings highlight the potential of SSA to improve the microstructure and performance of self-healing concrete, while the integration of advanced repair mechanisms ensures prolonged functionality and resilience under environmental stressors.
The review also identifies existing challenges, including the optimization of SSA processing methods and the compatibility of self-healing technologies with alternative binders. By summarizing state-of-the-art developments and proposing future research directions, this study underscores the potential of combining SSA and self-healing materials to revolutionize construction practices, promoting the development of resilient, low-carbon infrastructure.

This paper investigates the alternative use of sewage sludge ash (SSA) for the production of light weight aggregate (LWA) for sustainable construction The main objective is to investigate how SSA can be successfully reused to produce construction materials without reducing environmental contributions. The study examines the processes for converting SSA into lightweight aggregates, focusing on the technological processes and factors that make this application possible. Key benefits include significant reductions in the overall weight of concrete structures, reduced transportation and housing costs, and improved thermal insulation, which improves energy efficiency in buildings to the sky

In addition, the paper discusses the environmental benefits of implementing SSA in LWA operations, such as waste disposal reduction, greenhouse gas emission reduction, natural a will be preserved and also discusses technical challenges including the need for continuous quality improvement and compliance with regulatory standards. Research emphasizes the importance of quality qualitative and strategic approaches to ensure the reliability and efficiency of SSA-based LWAs.

Overall, this study presents SSA as a promising alternative for small aggregates, promoting a circular economy in the construction industry. In producing LWA by turning waste into a value-added product, SSA is a sustainable way to model modern construction practices, contributing to greener and more efficient industries.

Valorization of sewage sludge into ceramic materials, International Ceramics And Composite Materials Symposium , November 15-16,2024- ISparta, Turkiye.

The civil engineering industry is rapidly confronting two challenges: minimizing the harmful effects of construction on the environment and managing industrial waste. The concept of turning trash into resources is a fresh approach to addressing these problems, offering innovative solutions in line with the principles of sustainability and resource efficiency.

This study looks at the potential benefits of integrating various industrial wastes such as fly ash, slag, and recycled construction materials into civil engineering processes. Recycling these wastes may significantly reduce our reliance on virgin resources, landfill usage, and construction project carbon footprints.

The use of industrial byproducts in road construction, where recycled materials assist sustainable infrastructure, and in concrete production, where waste materials enhance the durability and performance of concrete, are two areas of focus. This article will also discuss the use of waste materials in soil stabilization, with a focus on the long-term benefits for both improved soil quality and structural stability.

This article, using case studies and the most recent research, demonstrates the economic and environmental advantages of waste valuation in civil engineering. It also discusses the opportunities and technical challenges of using these strategies more broadly. By encouraging the use of waste-derived materials and converting rubbish into valuable resources that aid in the creation of a built environment that is resilient and environmentally friendly, the civil engineering sector can set the norm for sustainable building.

– The civil engineering industry is rapidly confronting two challenges: minimizing the harmful effects of construction on the environment and managing industrial waste. The concept of turning trash into resources is a fresh approach to addressing these problems, offering innovative solutions in line with the principles of sustainability and resource efficiency.

This study looks at the potential benefits of integrating various industrial wastes such as fly ash, slag, and recycled construction materials into civil engineering processes. Recycling these wastes may significantly reduce our reliance on virgin resources, landfill usage, and construction project carbon footprints.

The use of industrial byproducts in road construction, where recycled materials assist sustainable infrastructure, and in concrete production, where waste materials enhance the durability and performance of concrete, are two areas of focus. This article will also discuss the use of waste materials in soil stabilization, with a focus on the long-term benefits for both improved soil quality and structural stability.

This article, using case studies and the most recent research, demonstrates the economic and environmental advantages of waste valuation in civil engineering. It also discusses the opportunities and technical challenges of using these strategies more broadly. By encouraging the use of waste-derived materials and converting rubbish into valuable resources that aid in the creation of a built environment that is resilient and environmentally friendly, the civil engineering sector can set the norm for sustainable building.

Keywords – Sustainability, Valorization, Industrial Waste, Resource Efficiency, Innovation.

Studies on the Valorization of mining waste in the
construction sector: A literature Review.

The effect of geopolymerization on eco-friendly concrete, Journées d’Etude de Génie Civil et Mécanique 2024« JEGCM24 »

Exploring alkali-activated aluminosilicate materials as sustainable alternatives : A view of activation processes depending on the calcium present in the system, Journées d’Etude de Génie Civil et Mécanique 2024« JEGCM24

This review investigates the integration of self-healing materials and sewage sludge ash (SSA) as a pioneering strategy for sustainable and resilient construction. Self-healing materials, with their ability to autonomously repair microcracks, offer a game-changing solution to enhance the durability and lifespan of infrastructure. Simultaneously, SSA, a by-product of wastewater treatment, is presented as a sustainable alternative to traditional cement and aggregates, reducing landfill waste and mitigating the environmental impact of construction activities.

The review synthesizes current advancements in combining these two technologies, focusing on their mutual benefits for mechanical properties, environmental sustainability, and structural integrity. It highlights the ability of SSA to improve the microstructural properties of concrete while preserving the functionality of self-healing agents, such as bacterial spores and polymer capsules. Furthermore, it discusses the challenges of optimizing SSA integration and ensuring compatibility with self-healing systems.

By analyzing recent developments and identifying research gaps, this review underscores the transformative potential of this dual approach. It envisions a future where SSA and self-healing materials jointly contribute to the development of eco-friendly and durable infrastructure, aligning with global sustainability and circular economy goals.

Sewage sludge ash (SSA) has emerged as a promising supplementary cementitious material (SCM) to enhance the performance and durability of cementitious materials This paper presents a comprehensive review of the characterization and consumption of SSA role in cement structure gives. Chemical composition analysis reveals the presence of silica, alumina, and other oxides important for pozzolanic reactivity. Mineralogical analysis identifies crystalline and amorphous phases, elucidating the potential of SSA. Physical properties such as surface specificity and particle size distribution influence the performance and mechanical properties of cementitious materials Evaluation of pozzolanic activity by different methods determines the amount of SSA contribution to strength development. The study of hydration kinetics clarifies the early life and long-term performance of cementitious systems containing SSA. Technical testing shows increased compressive, tensile and flexural strength of SSA-modified concrete. Developmental performance studies confirm resistance to chloride penetration, sulfate attack, alkali silica reaction (ASR), and carbonation, ensuring durability of SSA-based cement products This study provides valuable insights into Effective application of SSA characteristics and applications to sustainable building practices Simple.

Fresh and hardened proprieties and durability of self compacting repair mortar made with ceramic powder as cement substitute

Valorization of mining waste into construction materials: Literature review

Effect Of Using Phosphate Sludge In Geoplymerization: A Review

Development of geopolymer binders based on industrial waste with different treatment methods: A review

Disposal of waste glass derived from bottle or packaging glass, flat glass, domestic glass is one of the major environmental defies. Moreover, the remnants of bricks resulting from the remnants of buildings are also considered an important factor in polluting the environment due to the difficulty of filling or getting rid it. The aim of this study is to valorize these wastes through chemical activation to be an environmentally friendly material. The Microstructure, compressive strength, setting time, drying shrinkage, water absorption of different pastes produced by clear glass (CG), green glass (GG) and brick waste (BP) activated were tested and recorded after curing for 3, 7, 28 and 365 days. Five samples of pastes were mixed in proportions represented by: 100% GP (GP), 100% GGP (GGP), 100% BP (BP), 90% GP + 10% BP (GPB) and 90% GGP + 10% BP (GGPB). Various parameters considered in this study include sodium hydroxide concentrations (10 mol/l); 0.4 as alkaline liquid to binder ratio; 2.5 as sodium silicate to sodium hydroxide ratio and cured at 60°C for 24 hours. Experimental results revealed that the addition of 10% of BP resulted in an increased strength performance of geopolymer paste especially with GGPB compared to GGP in 365 days. In addition, the 10% amount of BP increases the absorption and shrinkage rate of geopolymer pastes (GPB and GGPB) by reducing the setting time. SEM results revealed that the addition of BP and GP resulted in a dense structure.

Utilisation des solutions chimiques avec les déchets industriels pour créer des matériaux composites, Le 2ème colloque national de chimie (CNC2@2024) 6 - 7 mai 2024

Wastewater generated from wastewater treatment poses challenges for disposal due to high organic content and potential environmental impacts but alternative wastewater treatment options are being developed in concrete production research. This abstract looks at the feasibility and potential benefits of incorporating wastewater into concrete mixes. Through rigorous characterization and processing, sewage sludge can act as a filler, providing long-term benefits and improving concrete properties Challenges such as changes in water a it is a matter of internal and regulatory constraints of the dirt Yoga: Materials- Can address weed-management issues while promoting efficiency and sustainability.

Use of fly ash in the manufacture of ceramics to improve several properties,

Ceramic powder utilisation in mortar production.

A STUDY BETWEEN THE LITERATURE AND LABORATORY
EXPERIMENTS OF CHARACTERISTICS OF MORTAR FORMED BY
CALCINED KAOLIN

A bibliographic study on geopolymers and the valorization of mining waste, the 1st scientific days on materials and their applications (SDMA 2023) , Biskra.

,"Effect Of Temperature On Geopolimerization", The 1st Scientific Days on Materials and Their Applications
(SDMA’2023), Biskra.

this paper reviews the use of the waste product (ceramic industry) for construction purpose. Now a days they are rapid growth in urban andindustrial is more and the demand is being increased day by day. The waste generated from ceramic industry is usedas a partial replacement in cement. To eradicate the demand of construction material cement is being replaced in our project as ceramıc waste accordingly in the range of 0%, 5%, 10%, 20%, and 30% by weight of cement for mix. Self-compacting mortar mixtures were produced, tested and compared in terms of compressive, flexural and split tensile strength with the conventional Self-compacting mortar. These tests were carried out toevaluate the mechanical properties for the test results of 7, 14, 28 days for compressive strength, flexural Strength and split tensile strength. For this purpose, design parameters like water to binder ratio (w/b), water to cement ratio (W/C), superplasticizer dosage (SP) (kg/m3) and replacement percentage of ceramic waste are studied on the slump flow. It is observed that with respect to different grades of SCC, designed parameters affects the fresh and strength properties of SCC

Application of waste ceramic powder as a cement replacement in Self- compacting mortar”

The search for an alternative to cement has become an environmental and strategic necessity to reduce the effects of global warming and preserve the energy capacity of energy-importing and energy-exporting countries alike. Geopolymer materials are classified as green materials and may be the alternative solution proposed at the present time due to their advantages. The results of research and studies have shown that these geopolymer materials possess superior mechanical and physical properties, including high early strength, good chemical resistance, low shrinkage, and good thermal resistance. The rise in temperatures in recent years and the global warming scenario has led to an increase in demand for heat-insulating materials, especially in the construction sector. This review includes, based on previous research, previous knowledge of more about the basics of these geopolymer materials the raw materials that go into preparing these compounds and the factors affecting their properties. The good thermal performance of these compounds is considered important and vital to exploit in the production of efficient insulating materials, and it may be a sustainable solution in re-exploiting mineral waste in order to preserve natural resources.

Keywords: Geopolymer materials, Thermal resistance, The global warming, Heat-insulating, Mineral waste

Alkali-activation of aluminosilicate materials on geopolymerization,
1ere journée Scientifique en matériaux et ses application accueilli par Université de Mohamed Khider, Biskra, Algérie,2023.

Ce projet consiste à convertir les réseaux d’eau traditionnel dans lequel des outils traditionnel tels que des vannes traditionnelles sont utilisée a un réseau moderne dans lequel des vannes électriques également utilisée, des débits mètre électriques, ce réseau est contrôlé a distancé par une basse de données connecté à tous ces appareils, sachant que le réseau avec ses appareils est alimenté par l’énergie solaire.
Grace à ce projet nous avons essayé d’atteindre plusieurs objectifs notamment :
_Préservé les ressources primaire d’eau.
_Réduire les fuites d’eau et le gaspillage.
_La manière de gérer ce projet est une manière nouvelle et moderne.
_Intervention rapide et efficace afin de traiter les pannes au niveau du réseau avec précision et dans un court laps de temps.
_Préserver les ressource d’énergie électrique et les remplaces par l’énergie solaire.
_Etablissement d’une base de données indiquant le mode de distribution d’eau et le montant de la consommation.
_ Elaborer un plan d’action pour surveiller le réseau d’eau

Comprehending the mechanical characteristics of concrete is paramount for its efficient deployment in construction. This investigation endeavors to predict these properties utilizing equivalent mortar, furthering previous inquiries on the topic. Literature suggests a viable approach to create concrete through a method employing both natural and crushed aggregates. This technique considers the corresponding mortar, amalgamated with crushed (SC) and dune sand (SD), as a novel mortar. Implementing this method could curtail the consumption of natural resources while conserving the mechanical attributes in both fresh (flow) and hardened states (strength and durability). This approach aims to anticipate the mechanical performance of concretes formulated from equivalent mortar data. Five mixtures were constituted to discern the optimal blend from a binary amalgamation of crushed coarse aggregates (30% fraction 3/8 and 70% fraction of 8/15) sized 3.8mm and 8.15mm, alongside five mixed sand percentages: (30% SC+70% SD), (40% SC+60% SD), (50% SC+50% SD), (60% SC+40% SD), and (70% SC+30% SD). The application of super plasticizer was investigated, and the compressive strength function of coarse aggregate was ascertained at intervals of 7, 14, and 28 days. The mechanical strength was determined at the 28-day mark. The empirical study indicates that density attains its zenith when a 40% mortar is incorporated into the concrete matrix. Conversely, with a 50% SC composition within the mixed sand, the mechanical strengths achieve acceptable values with moderate CS dosages. Specification tests reveal that incorporating 50% to 70% mortar into the concrete matrix can yield high-quality concrete.

Comprehending the mechanical characteristics of concrete is paramount for its efficient deployment in construction. This investigation endeavors to predict these properties utilizing equivalent mortar, furthering previous inquiries on the topic. Literature suggests a viable approach to create concrete through a method employing both natural and crushed aggregates. This technique considers the corresponding mortar, amalgamated with crushed (SC) and dune sand (SD), as a novel mortar. Implementing this method could curtail the consumption of natural resources while conserving the mechanical attributes in both fresh (flow) and hardened states (strength and durability). This approach aims to anticipate the mechanical performance of concretes formulated from equivalent mortar data. Five mixtures were constituted to discern the optimal blend from a binary amalgamation of crushed coarse aggregates (30% fraction 3/8 and 70% fraction of 8/15) sized 3.8mm and 8.15mm, alongside five mixed sand percentages: (30% SC+70% SD), (40% SC+60% SD), (50% SC+50% SD), (60% SC+40% SD), and (70% SC+30% SD). The application of super plasticizer was investigated, and the compressive strength function of coarse aggregate was ascertained at intervals of 7, 14, and 28 days. The mechanical strength was determined at the 28-day mark. The empirical study indicates that density attains its zenith when a 40% mortar is incorporated into the concrete matrix. Conversely, with a 50% SC composition within the mixed sand, the mechanical strengths achieve acceptable values with moderate CS dosages. Specification tests reveal that incorporating 50% to 70% mortar into the concrete matrix can yield high-quality concrete.

Different types of activation of supplementary cementing materials

Geopolymerization is the chemical process that brings together all the reactions transforming solid rich in silica (Si) and alumina (Al), such as fly ash, blast furnace slag or clay, an alkaline activator, such as sodium hydroxide (NaOh) or potassium hydroxide (Koh), to form an alkaline solution, under different experimental conditions, into aluminosilicate gel. This chemical reaction, called polymerization, enables the elements present in the raw materials to bind together to form a solid three-dimensional network, similar to that of Portland cement. This network gives geopolymeric materials high mechanical strength. This is an alternative to traditional methods of manufacturing materials such as Portland cement, which generate significant quantities of greenhouse gases (CO2) during production. The reaction mechanism for geopolymer formation comprises three stages: a dissolution/hydrolysis stage, a restructuring stage and a final polycondensation stage. Several parameters can influence the geopolymerization process, such as the alumino-silicate source (precursor type), particle texture and morphology, particle size and specific surface, alkaline activator type and concentration, water content, the silica content, as well as temperature, which has an effect not only on the reaction rate, but also on the microstructure and mechanical properties of the geopolymers, such as the texture of the final material, mechanical strength, homogeneity, porosity and thermal stability. Experimental studies and tests are often carried out to determine the appropriate temperature parameters for obtaining the desired properties of the geopolymer material.

The use of sewage sludge ash, also known as sewage sludge incineration ash (SSIA), as a construction material has gained attention in recent years. This study aims to investigate the effect of SSIA on the durability of equivalent mortar exposed to high temperatures. The exposure of mortar containing SSIA to high temperatures can have various effects on its durability. Some of the potential effects include a reduction in mechanical strength, degradation of the microstructure, weight loss, and the formation of new mineral phases. However, these effects can vary depending on the composition of the SSIA and other components of the mortar, as well as the specific conditions of high-temperature exposure. Further experimental studies are needed to provide more accurate evaluations of the impact of SSIA on the durability of equivalent mortar exposed to high temperatures.

Sludge valorization, also called sludge management, is an important field in the treatment of wastewater and solid waste worldwide. Sludge is the solid byproduct generated during the treatment of wastewater in wastewater treatment plants. They often contain organic matter, mineral elements and other contaminants, making them potentially harmful to the environment if not properly managed. However, there are many ways to recover sludge and use it beneficially rather than simply disposing of it. The areas of sludge recovery are: Composting, Agricultural use, Energy production, Biogas production and Production of construction materials. Using sludge to make bricks has many environmental benefits, including reducing waste, reducing demand for natural resources, decreasing greenhouse gas emissions, and creating sustainable building products. However, it is essential to comply with local and national environmental regulations and implement strict quality controls to ensure the safety and quality of bricks made from sludge.

Achieving environmentally friendly compounds with high mechanical resistance, lower density, and high thermal resistance is a topic of research for most of those interested in this field. Geopolymers are threedimensional amorphous materials made of aluminosilicates in a normal environment or at high temperatures through alkaline activation of aluminosilicate materials. This activation, along with Add a chemical foaming agent (aluminum powder, hydrogen peroxide, sodium oleate...) led to the synthesis of inorganic foam. Geopolymer foams are high temperature resistant materials characterized by mechanical and chemical stability and low post-foaming shrinkage. Pore size is directly related to changing the concentration of the foaming agent, and studies have shown that, by tracking CT images, up to 24% open porosity can be achieved without significantly affecting other properties. addition to geopolymers enjoying these advantages, we find some studies interested in obtaining other advantages, including adding another factor that (PCM).Thermal properties of geopolymer concrete (GPC) are enhanced by adding phase change material (PCM) capsules. Thermal and structural tests were conducted to investigate the effects of capsules on the properties of produced GPC. The produced thermally enhanced GPC can reduce heat transmission to indoors in the hot climates and its compressive strength is acceptable for nonloadbearing wall components.

This study examines the effect of aluminum (Al) waste additions on the mechanical performance of mortars at high temperatures. The tested mortars have been formulated with different proportions (0%, 2.5%, 5%, 7.5%, and 10%) by weight of sand after being exposed to five temperatures (50 °C, 150 °C, 200 °C, 400 °C, and 600 °C) without imposed load during heating. Workability, setting time of cement, air content, density, mass loss of mortar, thermal conductivity, porosity and mechanicals strength have been examined. The test results indicate a considerable decrease in workability and strength density of the mortar with the addition of Al. This composite has a well thermal conductivity result with 2.5Al and environmentally friendly than ordinary mortar. Further, the experimental data obtained have suggested that the compressive and the flexural tensile strength have been significantly reduced by 90 % in the mortar samples incorporating 10% Al after being exposed to the high temperature of 600 °C. Moreover, the mechanical strength of that mortar has been quite high at the age of 28 days at elevated temperatures in comparison with that measured at 20 °C. The strength of the mortar with Al can be sufficient for some applications where a lightweight, low-strength mortar is required. The use of Al in the production of low-strength concrete can contribute to more sustainable construction.

This study examines the mechanical effects of the addition of transparent glass in the form of waste glass powder on the mechanical properties of concrete in aggressive environments.Glass is used as an additive after conversion to fine powder and mixed with cement at 0% , 5% and 10% For the construction of concrete with additives and then poured into molds. And then treated in fresh fresh water, salt solution where the salt is 5% sodium chloride and finally in MgSO4 solution at 5% concentration for 7, 14 and 28 days, then mechanical tests are performed when the test used in this research is compressive strength and porosity. It was observed that there were differences in compressive strength when immersed in different solvents. Samples immersed in water have higher resistance than those immersed in sodium chloride MgSO4 solution and increase with immersion time. The results show that the addition of glass powder improves the flow of concrete, also it further consolidates the cementitious matrix which makes it difficult for aggressive compounds to penetrate into the concrete. Keywords: glass, addition, concrete, durability, aggressive environment,Porosity, Compressive Strength.

Several studies analyzed the effect of these additions on the physical and mechanical properties as well as the durability of concrete and mortar. However, few studies were conducted on the effect of local metakaolin on mechanical properties and durability of mortar. The main purpose of this paper is to analyze the performance of mortar with local metakaolin. The preparation of the metakaolin was carried out by calcination of kaolin at a temperature of 850 °C for a period of 3 hours according to a previous study of one of the authors.

In the construction field, the current research is oriented to the recovery of materials in general, is especially local materials to fight both the soaring prices that knows the way and at the same time ensured the balance nature by solving the problem of pollution that allows the survival of several species that are the major links to the balance of nature. The objective of our work is to lighten the micro-concrete by adding different percentages of polystyrene, and to improve the fluidity and the mechanical strength of the micro-concrete by the incorporation of adjuvant. The results obtained from this research confirm that the rate of 30% of polystyrene gives the most alleviation, 1.5% of adjuvant gives good fluidity and increases the mechanical strength.

The purpose of this study is to recover mineral residues as an additive in cement-based building materials. It is part of a sustainable development approach. The use of recovered and recyclable industrial residues in partial replacement of Portland cement reduces greenhouse gas emissions and results in the manufacture of cement with a lower environmental impact. Using various experimental techniques, particular attention is paid to the behaviour of the ceramic powder finely crushed and chemically activated associated with Portland cement. This study confirms the improvement in the physicochemical and mechanical properties of cements with the addition of ceramic powder, which augurs well for its use as a cement . Keywords: Sanitary ceramic waste; Fillers, Mortars; Properties

This paper investigated the effects of brick dust and metal fiber on the mechanical and physical properties of cement mortars exposed to high temperatures experimentally and statistically. For this purpose, the mixes containing marble dust (0%, 5%, and 10% by volume) and metal fiber (0 kg/m 3 , 1 kg/m, 2 kg/m 3 , 5 kg/m 3 ) were prepared. The cement mortars' compressive strength and porosity value were determined after exposure to high temperatures (300, 500, and 700 C). The percentage of brick dust, amount of metal fiber, and degree of temperature were changed to explore their effects on specimens' compressive strength and porosity values. Finally, experimental findings were compared with statistical results, and a good agreement between them was achieved. Keywords: brick Dust, Metal Fiber, Cement Mortar,Temperature, Porosity, Compressive Strength.

The objective of this research work is to study and better understand the behavior at high
temperatures of fiber concretes and the effect of the evolution of the temperature on their
mechanical behavior, by evaluation of the loss of residual mass, and the resistance residual in
compression and tension. The concretes are subjected to different heating-cooling cycles up to
a maximum temperature of 300°C ; 500°C and 700°C at the age of 28 days. This study
showed that the residual strength of fiber-reinforced concrete subjected to a very high
temperature decreased compared to concrete (not subjected to a very high temperature).
Keywords: Fiber concrete, Metallic fibers, Cement, high Temperature, mechanical
characteristics.

this study examines the effect of aluminum (Al) waste additions on the mechanical performance of mortars at high temperatures. The tested mortars have been formulated with different proportions (0%, 2.5%, 5%, 7.5%, and 10%) by weight of sand after being exposed to five temperatures (50 °C, 150 °C, 200 °C, 400 °C, and 600 °C) without imposed load during heating. Workability, setting time of cement, air content, density, mass loss of mortar, thermal conductivity, porosity and mechanicals strength have been examined. The test results indicate a considerable decrease in workability and strength density of the mortar with the addition of Al. This composite has a well thermal conductivity result with 2.5Al and environmentally friendly than ordinary mortar. Further, the experimental data obtained have suggested that the compressive and the flexural tensile strength have been significantly reduced by 90 % in the mortar samples incorporating 10% Al after being exposed to the high temperature of 600 °C. Moreover, the mechanical strength of that mortar has been quite high at the age of 28 days at elevated temperatures in comparison with that measured at 20 °C. The strength of the mortar with Al can be sufficient for some applications where a lightweight, low-strength mortar is required. The use of Al in the production of low-strength concrete can contribute to more sustainable construction.

Abstract: In recent years, due to the modern lifestyle, industrial and technological progress has led to a significant increase in the quantity and quality of waste. Waste accumulation problem every year is all over the world. The use of materials from waste in buildings compensates for the lack of natural resources, solves the problem of waste management and provides an alternative technique for protection of the environment.

In Algeria, the Ministry of Environment demonstrated that the recycling market is estimated at 23 billion
Algerian dinars (about 260 million USD). In this vision, policy makers aspire to establish a real industry for recovery and recycling of waste through the development of several sectors such as plastics, aluminum paper and cardboard, metals, glass, wood, etc. This review assesses Aluminum waste (Al) in concrete as a substitute for aggregates and cement. The physical, mechanical and environmental properties of the materials obtained by substitution of raw materials by Al waste were examined and compared to reference materials. Mining waste in cementitious materials offers good compressive strengths, while the porosity of the concrete and/or mortar is a factor influencing its toxicity.

In recent years, due to the modern lifestyle, industrial and technological progress has led to a significant increase in the quantity and quality of waste. Waste accumulation problem every year is all over the world. The use of materials from waste in buildings compensates for the lack of natural resources, solves the problem of waste management and provides an alternative technique for protection of the environment.

In Algeria, the Ministry of Environment demonstrated that the recycling market is estimated at 23 billion
Algerian dinars (about 260 million USD). In this vision, policy makers aspire to establish a real industry for recovery and recycling of waste through the development of several sectors such as plastics, aluminum paper and cardboard, metals, glass, wood, etc. This review assesses Aluminum waste (Al) in concrete as a substitute for aggregates and cement. The physical, mechanical and environmental properties of the materials obtained by substitution of raw materials by Al waste were examined and compared to reference materials. Mining waste in cementitious materials offers good compressive strengths, while the porosity of the concrete and/or mortar is a factor influencing its toxicity

The combined use of silica fume (SF) and ceramic waste (CW) for the production of mortar is studied. Sand isreplaced by 5%, 10%, 15% and 20% of CW while a fixed 5% percentage (% wt of cement) of SF is used. The resultsshow that the best results are obtained by using silica fume and ceramic waste sand with 15% weight of sand and5% wt of cement. With the addition of sand ceramic waste (SCW), the mortar compressive strength and densityincrease, while the porosity displays an opposite trend. The experimental analysis is complemented with theore-tical considerations on the matrix strength and related improvements in mechanical behavior. It is shown that theagreement between the experimental values and the estimated values is good.KEYWORDSMortar; silica fume; ceramic waste; full factorial arrangement; mechanical properties1 IntroductionThe big topic of importance today in cement and concrete technology is the recycling and reuse ofindustrial waste and by-products, like ceramic and brick wastes [1]. Some recent studies have proven thatthe use of the remnants of inorganic industrial produces in the production of concrete can makesustainable ceramics industry range from 3% to 7% of daily production [2]. Therefore, recycling it allowsit to be used in the construction of many different buildings [3]. After recycling this waste, it wasconsidered to be coarser than the cement particles, which is usually as fine and coarse aggregate in theconcrete mixture, up to 35% of tile waste [4].According to research by Kannan et al. (2017), replacing part of the cement with micro-ceramic powderled to the good improvement of the outstanding mechanical properties of high-performance concrete [5].MCP has been classified as a material rich in aluminum silicate which indicates significant activity ofpozzolanic [5]. The (C-S-H) and (C-AS-H), as the two major strength transfer phases in Portland cement(PC), formed as a result of the consumption of Ca(OH)2 by the reaction of aluminosilicates insideceramic waste [6].Cement consumes a large proportion of carbon dioxide is emitted into the atmosphere during itsproduction, which causes many environmental problems [7]. The silica fume (SF) is one of thecementitious additions (SCMs) used due to its improvement concrete/mortar properties [8].This work is licensed under a Creative Commons Attribution 4.0 International License, whichpermits unrestricted use, distribution, and reproduction in any medium, provided the originalwork is properly cited.DOI: 10.32604/fdmp.2022.021970ARTICLEechT PressScience

geopolymer paste by alkaline solution (alkali + water glass) were investigated. (e e4ect of the combination of GP and BW on the
porosity and absorption of the prepared geopolymer paste was monitored and evaluated by both laboratory and analytical
methods. In this paper, three mortars were made with two sources of geopolymer containing 100% BW and 100% GP and blended
with 90% GP and 10% BW replacements by mass. (e compressive strength, porosity, and absorption of alkali-activated mortar
were concurrently examined. Furthermore, the laboratory results obtained were estimated by the general full factorial design
method. Finally, the analysis of variance was performed using the test results to analyze the importance of the e4ect factors and
their interactions on the selected responses. (e results concluded that mortar activated combined with 10% BW and 90% GP
could be utilized in the industry of construction with minimum pollution problems and environment-friendly building materials,
with the e4ect variables signi:cantly a4ecting the responses.

The combined use of silica fume (SF) and ceramic waste (CW) for the production of mortar is studied. Sand is replaced by 5%, 10%, 15% and 20% of CW while a fixed 5% percentage (% wt of cement) of SF is used. The results show that the best results are obtained by using silica fume and ceramic waste sand with 15% weight of sand and 5% wt of cement. With the addition of sand ceramic waste (SCW), the mortar compressive strength and density increase, while the porosity displays an opposite trend. The experimental analysis is complemented with theoretical considerations on the matrix strength and related improvements in mechanical behavior. It is shown that the agreement between the experimental values and the estimated values is good.

This paper presents an experimental study on the influence of metal fibers on the mechanical behaviour of mortar with glass sand. Four mortar mixtures with glass filler and metals fibers are manufactured. The specimens were prepared with three percentages of glass sand (0%, 5%, 10%) and 1%, 2% by vol of steel fibers. The Air-Entraining Agent (A-E-A) dosages at the ratios of 0.08% of cement weight were used. The mechanical tests were carried out on the specimens such as the compressive strength, the tensile strength and the porosity. The results showed that the tensile and bending properties of all different mixtures with fibers are significantly higher compared to the reference mortars. A remarkable decrease has been observed in water, density and compressive strength of mortar with chemical admixture. Moreover, the using 1% volume fraction of steel fibers and 10% glass sand, flexural strength of mortar was completely improved.

High performance concrete (HPC) has several advantages in building construction that cannot be achieved using conventional concrete in terms of strength durability, resistance to chemical attack, and workability of high performance concrete are high. The introduction of fillers and additives contributed to the improvement of high-performance concrete (HPC), other parameters also influence the performance of these HPCs, coarse aggregate fraction is known to strongly influence both fresh and hardened concrete’s properties. Consequently, selection of both content and particle size distribution for (HPC) mixture is an important issue regarding the predicted performance of concrete. For to make concrete more improvement , the porosity of the granular skeleton as well as the rheology of our HPC, 3/8 fraction of rolled gravel with smooth and rounded surfaces was introduced, in substitution for the crushed gravel of the same fraction , by testing various combinations of fractions 3/8 of rolled gravel and fraction 8/15 of crushed gravel in the present study, and based on previous results obtained the combinations 35,40 and 45% fraction 3/8 of rolled gravel and 65 , 60 and 55% fraction 8/15 of crushed gravel (binary granular system) respectively, gives a minimal porosity . Super plasticizer and four percentages of pozzolan were experimented. Compressive strength function of coarse aggregate was determined at 7, 14 and 28 days. Results have revealed that the mixtures with modified granule size distribution system ,1.5% of superplasticizer and 5% by weight of pozzolan allow an improvement in the compressive strength of 35.1% relative to the control concrete.

The high-temperature mechanical behaviour of a glass and brick waste alkaline to synthesize geopolymer mortar was studied. The mortar in question contained 100% glass powder GWP and 90% of a blend of brick waste GBWP, brick waste BWP and a solid activator (10 mol concentration of NaOH mixed with glass water (Na2SiO3). The material was tested during exposure to high temperatures to establish its density, weight loss, compressive strength, accessible porosity in water, expansion of pastes, XRD and TG-DSC analysis using an innovative methodology to notch the hydrated geopolymers paste specimens after exposed to five maximum temperatures, 100℃, 200℃, 400℃, 600℃ and 800℃ without any imposed load during the heating. The results were found that GBWP gave better values in compressive strength, reaching 38.3 MPa at 100℃ and other proportional values at 400℃, 600℃ respectively compared with GWP. As for the density, the high temperature contributed to its decrease, which caused the presence of high porosity at 800℃. On the other hand, the high temperature helped to improve the mechanical and physical behavior of BWP, where the resistance reached 24.91 MPa at 200℃. In addition, for the microstructure and different particles related to the interactions were identified through the XRD and TG-DSC analysis procedure, in order to know the highest temperatures that allow changing the structure and properties of this type of alternative binders.

Most previous research on the term of alkaline and thermal activation, applied in the presence of cement as a main constituent, mixed with industrial waste like (fly ash, slag, glass…) by certain percentages to give a geopolymers or alkali-activated materials for studying the chemical and physical, as well as mechanical behaviour. These methods carried out by chemical solutions such as (NaOH, KOH, Na2CO3…) by different concentrations to facilitate the solubility of the aluminates-silicates, it’s depending on the nature of (CaO-SiO2-Al2O3) system in mineral residues, also there is the thermal method cured at a differents temperature between (20 °C and 100 °C) for 24 h that according to studies and researchers, all these methods to protect the environment from the emission of gaseous pollutants into the atmosphere.

A review of a sustainable mortar with partial alternatives to ceramic and brick as a cementitious material

Recycling and recovery of waste are now considered as a solution for the future to protect the environment. The marble processing workshops on the other hand, generate a large amount of waste in the form of powder and small parts. Due to these facts, the aim of this study is to valorize marble waste in the form of powder and crushed aggregates (sand) as additions in cementitious matrix building materials. The characterization of the materials used to formulate mortars based on natural dune sand with marble powder and mortars based on mixed sand (dunes sand and crushed sand) and marble powder was measure. In this sense, several series have been studied, varying the addition rate of the marble powder in order to reduce the porosity of the cement matrix, using crushed marble sand to increase the granular cohesion and using of a reducing water admixture (MEDAPLAST SP40) for more performance mortars. Very appreciable results were observed for a dosage of 15% of marble powder and for the combination of 15% of marble powder with 20% of crushed marble sand. This research recommends recycling 35% of marble waste in the cement matrix that contribute effectively to the preservation of the environment.

As part of protecting the environment from carbon dioxide emissions, all research aims to reduce the use of cement in concrete with cheaper and energy efficient materials. Geopolymer mortar is an environmentally friendly mortar made from industrial solid waste and by-products such as crystalline slag (CS). This research aims to produce a geopolymer mortar from local materials available in Algeria which are not sufficiently valued at present. The aim of this study is to provide geopolymer mortar at high temperatures, operating with a constant hardening temperature of around 60° C. The alkaline activator used in this study was a combination of sodium silicate (Na2SiO3) and 10 M NaOH solution. In addition, crystalline geopolymer mortars (MCS) as the binder material at a curing temperature of 60 °C, ratios of two mixtures of binder were prepared by substituting the sand with 40% CS and 100% CS. For this purpose, the mortar sample with the highest compressive strength was subjected to temperatures of 200, 400, 600 and 800 °C for exposure times of 10 °C per minute and changes in temperature and changes in the physical and mechanical properties was analyzed. As a result of the experiments, the highest mechanicals values were obtained from the mortar samples with a 40% CS content. Following the high temperature tests, 400 °C and 600 °C were determined as critical temperatures for changes in mechanical properties and changes in physical properties, respectively. However, the geopolymer mortars lost around 60% of strength at 800 °C which is the final temperature.

The present study aims primarily to investigate the possibility of assessing the physico-mechanical behavior of concrete incorporating marble waste or marble powder as a partial replacement for cement using destructive and non-destructive testing methods. Indeed, in this work, cement was partially replaced with marble powder at six different substitution levels, i.e. 5, 10, 15, 20, 25 and 30% by weight, with 1.5% adjuvant (super plasticizer) for each mixture. The samples prepared were then analyzed. In addition, the physico-mechanical properties, in the fresh and hardened states, water-to-cement ratio, absorption and compressive strengths of the concrete samples were examined as well. Moreover, the compressive strength of concrete was assessed through non-destructive testing methods such as the ultrasonic pulse velocity and rebound hammer. Likewise, the relationship between the ultrasound velocity and compressive strength of concrete were also estimated after 3, 7, 28 and 90 days of curing. The findings of the study indicated that, at early age of curing, the values of the compressive strength and ultrasonic pulse velocity were quite small for all replacement levels, of cement with marble powder, between 15 and 30%. Nevertheless, when the curing period was increased, the compressive strength and ultrasonic pulse velocity of all the samples went up as well. In the end, a linear relationship was observed between the ultrasonic pulse velocity and compressive strength for all substitution levels of cement with marble powder.

Recently a full factorial design is an experiment allows the investigator to study the effect of each factor on the response variable, as well as the effects of interactions between factors on the response variable. The objective of this study is to identify the significant factors and interactions involved in maximizing compressive strength of geopolymer mortar when brick waste activated is used as cement. In this respect, experimental factors at two levels, which are alkaline activator type (Na2SiO3+ NaOH), curing temperature (40°C - 60°C) and cure duration (7-28 days), are selected as possible applicants affecting the compressive strength.

This study aims to valorize mineral residues as an addition to cementitious matrix building materials. It is part of a sustainable development approach. The use of recovered and recyclable industrial residues as a partial replacement of Portland cement in concrete reduces greenhouse gas emissions and results in the manufacture of concrete with less environmental impact. The use of crushed glass powder to replace clinker presents a promising way to recover and recycle waste. By taking advantage of different experimental techniques, particular attention is given to the behavior of the finely ground glass powder associated with Portland cement. Cement replacement by glass powder in the range 5% to 10%. This approach is based on the material properties and its effect on the properties of hardened concrete strength porosity, several parameters are considered, namely: The effect of filler, the effect of adjuvant and W/C, porosity, leading to the production of concrete local materials characterized by good strength, porosity and minimum acceptable durability.

The search for a cheaper binder using natural resources and industrial waste has become a major concern in the manufacture of cement. According to the literature, researchers have found that glass and marble waste in the form of powder can be introduced into cement to obtain a cheaper and less polluting cement.
In this study, we attempted to determine the strength of concrete containing glass powder and marble powder by partially replacing cement in concrete. Cement substitution by these mineral additions in the range of 5% to 10%. This approach is based on the properties of the material and its effect on the physical and mechanical properties of concrete. Several parameters are considered, namely: the effect of filler, the effect of the adjuvant and the ratio W / C, to lead, to the making of a concrete based on local materials characterized by good strength, porosity minimum and acceptable durability.

This study aims to valorize calcined kaolin powder as an addition to cementitious matrix building materials. The main purpose of this study is to formulate and analyze the performance of metakaolin mortars. The preparation of the metakaolin was carried o ut by calcining the Kaolin at a temperature of 800 °C for duration of 3 hours. A comparison of the results with a control mortar without addition is established. The observed results showed that the rate of substitution of 10% of cement by metakaolin increases the compressive strength and tensile strength at a young age.

The development of new building materials is the problem of time, where researchers trying to find inexpensive equipment adapted in line with the field of use, the use of additional materials in the cement industry continues to increase and is often called on these metal additions materials we get from natural sources or remnants of industrial materials. In addition, the use leads to a reduction of clinker consumption and contribute to solving environmental problems in a simple and economical manner. The main objective of this experimental work is to study the proportion of powdered glass and marble dust on the physical and mechanical behavior of the composite cement and mortar. The obtained results the results obtained show that the partial compensation of glass cement powder 10% give the best values.

This study examines the effect‘s additions of aluminum (AL) on the mechanical performance of mortars subjected to cycles of freeze-thaw. The research evaluated the density, compressive strengths and workability properties of mortar mixtures to which aluminum byproduct was added in different proportions (0%, 5% and 7.5 %,) by weight of cement. The effects of fast freeze-thaw cycles on the mechanical properties of aluminum waste mortar materials (MC, M5 and M7.5) are investigated on the basis of the experimental results. The test results indicate a considerable decrease in workability, mechanical resistance density of plain mortar with the addition of AL. The results also show that the strength of mortar with AL can be sufficient for certain applications, where light and low-strength mortar is required. Overall, the results of this study demonstrate the viability of using AL in the production of low strength concrete, where such usage can help toward a more sustainable construction.

A large amount of natural aggregates such as sand and fillers are being consumed in mortar production. At the same time production of solid waste from the demolitions and manufacturing units are also very high. The objective of this study is to identify the significant factors and interactions involved in behavior of mortar with partial replacement of waste ceramic used as alternative sand aggregate and it is compared with controlled mortar.
In this respect, experimental factors at two levels, which are sand, are replaced by waste ceramic for various percentages 5%, 10%, 15% , cure duration (7-28 days) and the strength is controlled. According to the full factorial analysis, at the 15% percentage level when waste is added to mortar with sand, the compressive strength will be good enough after 28 days. The results demonstrate that ceramic waste can be used in construction and prove cost effective technique concreting for the future.
The physic - mechanical analysis shows an excellent agreement between the measured and the estimated values for both the compressive strength and the porosity and only slight deviations were noticed for high percentage of ceramic content. The use of appropriate values of matrix strength and consideration of the improvement in mechanical behavior allow a good agreement between the experimental values and the estimated values. The results demonstrate that ceramic waste after substitution in the mortar can be used in construction industry and prove cost effective technique concreting for the future.

In this study, compressive strength values were measured at different curing times (7, 14 and 28 days). The alkali-activation of the brick and glass powder body with potassium water glass having the silicate modulus of 3.0. The 28-days compressive strengths, flexural strength and specific fracture energy of the specimens stored at 40 and 60 °C are evaluated. The storage temperature of specimens and the content of the alkaline solution have a significant influence on all mechanical properties of the studied materials.

Abstract: Recently a full factorial design is an experiment allows the investigator to study the effect of each
factor on the response variable, as well as the effects of interactions between factors on the response variable.
The objective of this study is to identify the significant factors and interactions involved in maximizing
compressive strength of geopolymer mortar when brick waste activated is used as cement. In this respect,
experimental factors at two levels, which are alkaline activator type (Na2SiO3+ NaOH), curing temperature
(40°C - 60°C) and cure duration (7-28 days), are selected as possible applicants affecting the compressive
strength.According to the full factorial analysis, at the 60 °C curing temperature level when brick waste
activated is added to mortar, the compressive strength will be good enough after 28 days. The physic -
mechanical analysis shows an excellent agreement between the measured and the estimated values for both the
compressive strength and only slight deviations were noticed for high curing temperature. The use of
appropriate values of matrix strength and consideration of the improvement in mechanical behavior allow a
good agreement between the experimental values and the estimated values .The results demonstrate that brick
waste after activation can be used in construction industry.
Keywords: Brick waste, Experimental design, Geopolymer mortar, Curing temperature

The objective of this study is to analyze the effect of the air entrainment on the fresh rheological properties as well as on the compressive mechanical resistances of the mortars. The hardened concrete contains a certain amount of randomly spread air, coming either from a drive during kneading or from the evaporation of the mixing water. The air quantity is in the order of 20 l / m3, ie 2% of the volume. However, the presence of a large volume of air bubbles causes the mechanical resistances to fall in compression. On the other hand, the use of air entrainment could improve the rheological properties of fresh concrete.

Experimental studies have been carried out to study the effect of air entrainment on compressive strength, density and ingredients of fresh concrete mix. During all the study, water cement ratio (w/c) was maintained constant at 0.5. The results have shown substantial decreasing in water and mortar density followed with decreasing in compressive strength of mortar. The results of this study has given more promising to use it as a guide for mortar mix design to choose the most appropriate concrete mix design economically.

This paper presents an experimental investigation on the performance of concrete with and without glass powder (GP) subjected to elevated temperatures. Mechanical and physicochemical properties of concretes were studied at both ambient and high temperatures. One of the major environmental concerns is disposal or recycling of the waste materials. However, a high volume of the industrial production has generated a considerable amount of waste materials which have a number of adverse impacts on the environment. Further, use of glass or by-products in concrete production has advantages for improving some or all of the concrete properties. The economic incentives and environmental benefits in terms of reduced carbon footprint are also the reason for using wastes in concrete. The occurrence of spalling, compressive strength, mass loss, chemical composition, crystalline phase, and thermal analysis of CPG before and after exposure to various temperatures (20, 200, 400, and 600oC) were comprehensively investigated. The results indicated that, the critical temperature range of CPG was between 400oC and 600oC.

This study examines the effect of the additions of silica fume and super plasticizer on the
mechanical performance of high performance concretes at high temperatures. The tested concretes are
formulated with 5% silica fume and two dosages of super plasticizers in the ratio of (2%, 2.5%) the
weight of cement after having been exposed to four maximum temperatures, 200 °C, 400 °C, 600 °C and
900 °C without any imposed load during the heating. The results obtained show that the mechanical
resistance at 28 day increases with the degree of temperature compared to that measured at 20 °C. On the
contrary, a clear decrease is observed between 600 °C and 900 °C. However, material composition seems
to have great influence on the mechanical strength.