Ahmed M. Soliman

• Ph.D, P.Eng
• Professor (Associate) at Concordia University

Among various ways to counter the effects of cracking and damage induced by exposure to elevated temperatures, self-healing appears to be a promising technique for maintaining construction materials' structural integrity and longevity. This research investigates the effectiveness and potential of autogenous self-healing for alkali-activated concret...

Rheological properties are critical for assessing self-consolidating concrete (SCC)’s performance and application. However, predicting these properties accurately, specifically plastic viscosity and yield stress, faces challenges due to inconsistent data, small sample sizes, and measurement inaccuracies, with the type of rheometer significantly imp...

The interest in implementing self-consolidating concrete (SCC) in major construction projects has increased significantly in recent years. This paper reports the results of an extensive survey of experimental data of more than 1700 SCC mixtures from over 100 studies published in the last decade. The survey included the SCC mixture proportioning, ke...

Changing concrete ingredients significantly affects its performance due to changing the type of hydration products formed. The stability of these hydration products will dominate concrete impact behavior before and after exposure to fire. Limited research had explored the role of activators, as the main ingredient of alkali-activated slag concrete...

The mechanism of sulfate attack on alkali-activated materials, particularly the alkali-activated self-consolidating concrete (AASCC), is complex and contradictory. This could be due to the wide range of precursor and activator materials used in the production of AASCC mixtures, which has called into question the reliability and validity of existing...

Several studies have investigated the properties of alkali-activated materials (AAM), considering it as a substitute of cementitious concrete. However, the studies on alkali-activated self-consolidating concrete (AASCC) are extremely limited. This paper investigated the properties of AASCCs utilizing ground granulated blast furnace slag (GGBFS) as...

There is a significant potential for Alkali-activated self-consolidating concrete (AASCC) to be used in the construction industry. AASCC combines the benefits of both self-consolidating concrete (SCC) and sustainable development. The aim of this study was to develop an experimental program to investigate the potential production of one-part AASCCs...

Civil engineers have always considered the use of new data technologies in the construction industry. Several methods were applied to the analysis and sort the available massive data targeting accurate prediction for the performance. With the advent of alternative binding systems to ordinary cement, developing a predictive model that can offset the...

Alkali activated material (AAM) is attracting the attention of the scientific community. It showed outstanding mechanical properties comparing to that of the ordinary Portland cement (OPC) concrete. Moreover, concrete is a brittle material; hence, its behaviour under tensile stress is more critical, specially, under dynamic loads such as impact loa...

In recent years, industrial waste disposal has become a major environmental issue. Researchers have reported several ecological, economic, and environmental benefits for recycling such wastes for making concrete. The addition of some wastes was found to improve concrete’s mechanical and durability performance due to their physical and chemical prop...

Cement is the most used inorganic building material on earth due to its versatility and low cost. Its worldwide production in 2019 amounted to about 4.2 billion metric tons, which has a significant environmental impact. Around 8% of the global anthropogenic carbon dioxide (CO2) emissions are released from the cement production process. Under curren...

Over the past few years, the construction industry has entered new challenges in production. One of the main challenges is utilizing solid waste as aggregates to achieve environmentally friendly construction materials. Moreover, with the advent of alkali-activated materials, as a replacement of cement, more potential for achieving sustainability be...

Rapid set accelerating agents are added to shotcrete mixtures to speed up the hydration process targeting short setting time and high early strength. Silicate-based and alkali-free are the two main accelerating admixture categories that are being used in shotcrete. The effectiveness of these accelerators varies significantly based on the chemical c...

Protective concrete structures are considered to be non-traditional structures. They must satisfy the required criteria that qualify them to resist fire and impact loads induced by bombs. Alkali activated material (AAM) as a green alternative to ordinary Portland cement needs more investigations to ensure their suitability for such structures. In t...

Cement industry consumes annually around 5% of total industrial energy and results in about 8% of the total global carbon dioxide emissions. Therefore, there is a burgeoning interest in finding alternative binders with lower environmental impacts. Among several promising alternatives, alkali-activated materials (AAMs) are attractive for many resear...

Utilizing waste rubber tires in concrete as a partial replacement of aggregate reduces its carbon footprint and modifies its performance. Several researchers have evaluated the properties of crumb rubber concrete (CRC). This article evaluated the potential of one of the most promising testing techniques for concrete (i.e., the stiffness damage test...

Bored and continuous flight auger (CFA) piles are two widely used cast-in-place reinforced concrete pile types that are constructed employing vastly different techniques. In this regard, the work presented herein has two main objectives: to compare the axial performance of CFA and bored concrete piles in sand; and to investigate utilizing a green c...

Shrinkage-reducing admixture (SRA) efficiency as a shrinkage mitigation technique has been proven for the alkali-activated slag (AAS) system. However, the controlling mechanism is a debatable subject. Moreover, it has been reported that SRA may retard strength development and slag hydration. Hence, this study explores the behaviour of SRA and its i...

The durability of zero-cement concrete or alkali-activated materials (AAMs) is a subject of controversy, especially when exposed to sulfate attacks. This can be due to the different elemental and microstructural compositions of the broad alkali-activated systems that exhibit different degradation mechanisms in sulfate-rich environments. Various par...

Bioaggregate based concrete (agroconcrete) is as low carbon, sustainable, and multifunctional building material. Limited resources are forcing scientific efforts to seek alternative materials from natural resources as additives in the partial replacement of cement. In addition, the wide availability of agricultural wastes makes them a suitable alte...

Chapter 15 Implementation of agricultural crop wastes toward green construction materials of This book, entitled Handbook of Sustainable Concrete and Industrial Waste Management and subtitled Recycled and Artificial Aggregate, Innovative Eco-friendly Binders, and Life Cycle Assessment, edited by Francesco Colangelo, Raffaele Cioffi, and Ilenia Fari...

The feasibility of producing “just add water” alkali-activated self-consolidated (AASCC) mixtures using multi-powder activators and various cement-less binder combinations was evaluated in this study. During this study, fresh properties for mortar mixtures were evaluated by conducting the mini-slump flow test. Moreover, the relative performance of...

This study investigated the potential of unifying construction and agricultural sectors’ goals to meet the global demand for green construction implementation. Saving natural resources and solving waste disposal of issues, through utilizing agriculture waste as a replacement for natural aggregate was adopted. Environmental-friendly controlled low s...

This paper aims to investigate the effect of fine recycled concrete powder (FRCP) on the strength of self-compacting concrete (SCC). For this purpose, a numerical artificial neural network (ANN) model was developed for strength prediction of SCC incorporating FRCP. At first, 240 experimental data sets were selected from the literature to develop th...

Abstract Alkali-silica reaction (ASR) is considered one of the most critical internal damaging mechanisms for concrete. Several specifications and testing methods have been used to evaluate concrete performance, undergoing ASR damage. This had led to enormous data in the literature, yet some are contradictory. Hence, the significances of geometry,...

This research compares the efficiency of basalt fiber reinforcement polymer mesh (BFM) and glass fiber reinforcement polymer mesh (GFM) to suppress ASR-Expansion and enhance the mechanical properties of ASR-damaged concrete. BFM has not often been utilized for concrete confinement but is significantly less expensive than GFM. Results showed that th...

Alkali-activated material (AAS) is a potentially sustainable alternative binding material for Portland cement. This study focuses on the development of AAS properties and their interrelationships. The nature of the activating media, including sodium oxide content (Na2O%) and silica modulus (Ms), is the main aspect of this work. The effects of Na2O%...

During hot and cold weather, initial mixing water temperature is a critical parameter in controlling the fresh and hardened properties of cement-based materials. With the advent of Alkali Activated Materials (AAMs), the effectiveness of such a technique becomes questionable as the hydration mechanism differs from that of the ordinary Portland cemen...

Cement is the main binding material for many military and civilian applications. The response of cement-based materials to kinetic energy, transferred by impact loads, always had attracted researchers working in the protective structures field. As an immerging binding material, alkali-activated material responses to different types of loads, especi...

This study investigates the feasibility of enhancing construction materials sustainability using bio-based by-products as a partial replacement for natural sand. Controlled low strength material (CLSM) was selected as a practical application, thanks to its low strength requirements. The fine black spruce residual was added to different strength lev...

Implementing waste materials in construction applications represents an effective solution for many waste management problems. This study presents an innovative solution for application of treated oil sands waste (TOSW) in grout mixtures used for micropiles construction. Effects of employing these grout mixtures on micropiles cross-section, surface...

This research focuses on correlating the degree of expansion as a result of Alkali-Silica Reaction to mechanical properties and durability indices of hardened concrete. Degradation of six concrete mixtures incorporating Spratt aggregate with and without fused silica stored at 38 °C and 95 ± 5% RH were monitored for 12 months. Compressive and tensil...

With the advent of new materials that possess enhanced properties, designing concrete mixtures targeting a certain strength is a misleading concept. Hence, shifting to performance-based design is becoming a global trend that allows more flexibility in selecting and pro-portioning concrete ingredients. This study investigates the potential of increa...

The degree of ASR expansion at the strengthening time is critical. Fiber reinforcement polymer is an adequate strengthening material for ASR. The earlier strengthening, the better the performance of strengthened elements. BFRP is a strong competitor for CFRP at a lower cost. a b s t r a c t Recently, many composite materials have been used to stren...

Concrete is the most widely used construction material. However, large volumes of natural resources and raw materials are being consumed in concrete production. This reduces concrete industry sustainability and increase its environmental negative impact. On the other hand, the agriculture sector is facing problems that require more efforts in agro-...

Concrete is the most widely used construction material. However, large volumes of natural resources and raw materials are being consumed in concrete production. This reduces concrete industry sustainability and increase its environmental negative impact. On the other hand, the agriculture sector is facing problems that require more efforts in agro-...

Concrete is the most widely used construction material. However, large volumes of natural resources and raw materials are being consumed in concrete production. This reduces concrete industry sustainability and increase its environmental negative impact. On the other hand, the agriculture sector is facing problems that require more efforts in agro-...

Concrete is the most widely used construction material. However, large volumes of natural resources and raw materials are being consumed in concrete production. This reduces concrete industry sustainability and increase its environmental negative impact. On the other hand, the agriculture sector is facing problems that require more efforts in agro-...

High demand of natural resources and the disposal problem of agricultural wastes are two main challenges faced by construction and agriculture sectors. Therefore, the use of agro-waste in the construction industry can be an optimum solution. In response to the increased interest in sustainable construction materials, many agricultural waste materia...

Alkali activated systems are considered the third generation of binding systems. Alkali Activated systems are characterized by low carbon dioxide emission and superior mechanical and durability performance compared to cement-based systems. This study will focus on characterizing the performance of alkali-activated slag (AAS) mortar. Sodium hydroxid...

The application of crumb rubber from recycled tires has been used in construction as a replacement for the aggregate and fine sand in concrete. The use of these materials can improve concrete performance and may enhance its properties along with minimizing the cost. This paper investigates the effect of 10% replacement of sand with fine crumb rubbe...

Alkali-silica reaction is a prevalent type of deterioration in concrete infrastructure. In laboratory testing, prisms are cast horizontally and subsequently tested for expansion in the vertical direction (ASTM C1293). This may not adequately relate to actual cast-in-place concrete structures. In this research, prisms were cast in horizontal and ver...

23 Evaluation of concrete durability required to achieve with less cost and rapid implementation. 24 In this research, the possibility of using electrical resistivity tests as a non-destructive test for 25 assessing the properties of FRC concrete incorporating different types of fibers was 26 evaluated. The test results of the electrical resistivit...

The environmental and ecological impacts associated with concrete industry represent a major sustainability challenge. However, employing materials that would otherwise be considered waste in designing concrete mixtures can increase its sustainability along with reducing harmful impact of waste disposal. Therefore, this study attempts to increase c...

In the present study, self-healing of cracks in concrete under different environmental exposure was investigated. Pre-cracked mortar specimens were exposed to three different environmental conditions including cyclic temperature/relative humidity, cyclic wetting/drying, and continuous submersion in water. Change in crack width in each specimen due...

Cement industry produces large amounts of carbon dioxide causing many environmental problems including global warming and air quality deterioration. As an alternative to cement, many studies have been conducted on alkali-activated materials (so-called geopolymer). Geopolymer showed similar or better mechanical and durability performance compared to...

Alkali-activated binder (so-called geopolymer) is an eco-friendly binder alternative for cement. It is characterized by a very low carbon footprint. However, shrinkage of geopolymer materials is still one of the main challenges that impede its in-situ applications. The purpose of this study is to investigate the shrinkage behaviour of geopolymer mo...

Controlled Low-Strength Materials (CLSM) is a self compacted self-leveling cementitious material with compressive strength of 8.3 MPa or less. It is used as an alternative of soil backfill materials in geotechnical and infrastructure applications. This study investigates the effects of incorporating Treated Oil Sand Wastes (TOSW) as a partial repla...

A novel eco-efficient technology for the construction of pavements and sidewalks using high recycled volume Two-Stage Concrete is proposed. Two-Stage Concrete is a special type of concrete, which is distinguished by its high coarse aggregate content and exceptional placement, whereby aggregates are first pre-placed in the mold then injected with a...

This study investigates the potential of using crushed concrete as aggregates to produce green and sustainable concrete. Crushed concrete was sieved to powder fine recycled aggregate (PFRA) less than 80 µm and coarse recycled aggregates (CRA). Physical, mechanical, and microstructural properties for PFRA and CRA were evaluated. The effect of the ad...

This study investigates the potential of using crushed concrete as aggregates to produce green and sustainable concrete. Crushed concrete was sieved to powder fine recycled aggregate (PFRA) less than 80 µm and coarse recycled aggregates (CRA). Physical, mechanical, and microstructural properties for PFRA and CRA were evaluated. The effect of the ad...

This study pioneers the concept of fibre-reinforced preplaced aggregate concrete through premixing and preplacing steel fibres with aggregates in the formwork, then injecting a flowable grout. Unlike in conventional steel-fibre reinforced concrete where the fibre dosage, length and aspect ratio are hampered by workability considerations, the influe...

Two-stage concrete (TSC), also known as preplaced aggregate concrete, is produced through placing coarse aggregate particles in the formwork and subsequently injecting grout to fill the interparticle voids. The ability of the used grout to flow around the preplaced aggregate particles and effectively fill voids has a predominant effect on the TSC p...

In this study, the effect of fire on the impact resistance of a novel hybrid fiber-reinforced engineered cementitious composite incorporating short randomly dispersed shape memory alloy and polyvinyl alcohol fibres (HECC-SMAF) was investigated. A two-parameter Weibull distribution was used to analyze variations in experimental results in terms of r...

The anchor-jointed precast structural shear wall system is a novel structure. In this system, precast shear walls are jointed together and/or to the foundation using threaded steel anchor bolts. This new joining technique makes the construction process of precast shear walls easier and faster. Moreover, steel anchor bolts at the connection are desi...

There is currently dearth of information on the durability of two-stage concrete (TSC) to physical and chemical sulfate exposure. TSC differs from conventional concrete in many ways including its placement technique, high aggregate content and the use of very flowable grout. Therefore, available data on the behavior of conventional concrete under s...

Two-stage concrete (TSC), also known as pre-placed aggregate concrete, is characterized by its unique placement technique, whereby the coarse aggregate is first placed in the formwork, then injected with a special grout. Despite its superior sustainability and technical features, TSC has remained a basic concrete technology without much use of mode...

Evaluating expansion of self-compacting concrete (SCC) incorporating recycled concrete aggregates (RCA) is a commonly used criterion in the production of this type of concrete. However, monitoring the expansion is a complicated and time consuming process. In this research, an Artificial Neural Network (ANN) model was developed to predict the expans...

Controlled low-strength material (CLSM) is a self-levelling cementitious material. It is not concrete nor soil-cement, however, it possesses properties similar to both. CLSM is widely used as a replacement for soil-cement material in many geotechnical applications such as structural backfill, pipeline beddings, void fill, pavement bases and bridge...

Cementitious materials are widely used as a construction material all over the world. However, cement industry has high environmental impact such as the release of CO2 and the consumption of natural resources for its manufacturing energy. Therefore, reducing cement consumption is vital to achieve sustainable green construction practices. In this st...

An experimental study was conducted to evaluate the impact behaviour of an innovative hybrid-fibre engineered cementitious composite (ECC) incorporating randomly dispersed short shape memory alloy fibres (SMA). A modified drop weight test was conducted on specimens from various ECC mixtures with and without SMA fibres. The impact behaviour was eval...

Self-compacting sand concrete (SCSC) is a special type of self-compacting concrete characterized by the use of aggregates with a maximum size less than 5 mm. SCSC can incorporate large amounts of fine recycled concrete materials, making it a sustainable and green environment constructional material. Therefore, the present study investigates the mec...

The successful construction of many infrastructure projects largely depends on innovative geotechnical engineering solutions. For example, tunnels, tailing dams, road beds, and foundations for large structures represent significant societal investment that can benefit from innovative use of construction materials and sustainable construction practi...

The impact behaviour of an innovative hybrid-fibre engineered cementitious composite (ECC) incorporating randomly dispersed short shape memory alloy (SMA) fibres was experimentally investigated. A drop weight test was conducted on different ECC mixtures to evaluate their ability to dissipate energy and sustain multiple impact loads. The experimenta...

Oil sands drill cuttings waste represents one of the most difficult challenges for the oil sands mining sector. Reducing the amount oil sands drill cutting waste sent to landfill offers one of the best solutions for waste management. The present work offers an innovative solution for the recycle and reuse of treated oil sands drill cuttings waste (...

Two-stage concrete(TSC), also known as preplaced aggregate concrete, is produced through placing coarse aggregate particles in the formwork and subsequently injecting grout to fill the interparticle voids. The ability of the used grout to flow around the preplaced aggregate particles and effectively fill voids has a predominant effect on the TSC pr...

Grouted helical piles allow significant increase in pile capacity with low additional cost over that of conventional helical piles. They can be particularly advantageous in sites where installation disturbance can reduce or even eliminate the pile shaft resistance. For helical piles with slender shafts, a grout column offers increased buckling resi...

Ultra-high performance fiber-reinforced concrete (UHPFRC) is an emerging material exhibiting superior mechanical and durability properties. However, its application in precast concrete tunnel linings is lagging due to lack of experimental data and adequate design provisions. This study is a preliminary investigation of UHPFRC tunnel lining segments...

This paper presents an assessment of geo-environmental properties for the incorporation of recycled gypsum, produced from gypsum waste, as an additive material in earthwork projects. In this study, the solubility of Fluorine, Boron and hexavalent Chromium and the emission of hydrogen sulfide gas refer to geo-environmental properties. To achieve thi...

The mechanical properties of two-stage concrete (TSC) made with various grout mixtures and incorporating single, binary, and ternary binders were investigated in the present study. Different supplementary cementitious materials, including class F fly ash, silica fume and metakaolin were added as partial replacement for ordinary Portland cement. Mec...

Steel corrosion induces distress in concrete structures, resulting in the cracking and spalling of the concrete cover, which accelerates further damage. Chloride ions (Cl–) and carbonation are the primary causes of steel corrosion in concrete. This study investigates the effects of Cl– in precast concrete tunnel lining (PCTL) segments through condu...

Precast concrete shear walls are used to resist lateral loads in low- to medium-rise buildings. This paper introduces an innovated joining technique for these precast walls that will reduce the possibility of concrete damage and capital loss during earthquake events. The proposed technique consists of precast panels joined together and to the base...

Tunnels play a key role in facilitating the movement of people, goods, and services. The functionality of tunnels depends on the structural and durability performance of its lining system. Tunnel lining systems act as lines of defense against large overburden loads and complex geotechnical surrounding conditions. In this study, the structural behav...

Tunnels play a key role in facilitating the movement of people, goods, and services. The functionality of tunnels depends on the structural and durability performance of its lining system. Tunnel lining systems act as lines of defense against large overburden loads and complex geotechnical surrounding conditions. In this study, the structural behav...