Obinna Onuaguluchi

The disposal of Waste Glass (WG) in landfills is a critical environmental challenge faced by most countries around the world. Therefore, reusing of crushed glass as aggregates reduces the utilization of natural resources, thereby minimizing greenhouse gas emissions and increasing the sustainability of natural aggregates. Although it has a near to z...

In this study, the effect of Nano-Fibrillated Cellulose (NFC) on the sulfate resistance of cement composites was investigated. Plain and 0.5% steel fiber reinforced cement paste and mortar mixtures (FRM) modified with 0.1% NFC were evaluated. Changes in mass and tensile strength of specimens subjected to alternate immersion in 5% Na2SO4 solution an...

Retarded hydration and delayed microstructure development could reduce the early-age mechanical performance of fiber reinforced, High Volume Fly Ash (HVFA) cement composites. In this study, the effects of the pH-neutral Sodium Sulfate (SS), as a chemical activator on the early-age matrix mechanical strength development and bond performance of a ste...

A realistic forecast of the impact of CaCl2-blended acrylic polymer (CP) emulsions on steel reinforcement corrosion is difficult without a detailed study. This is traceable to the conflicting effects of cement additives on the chloride threshold value, pore solution chemistry, and matrix resistivity. Hence, in the study reported herein, the actual...

The utilization of mine tailings (MT) as feedstocks for the production of construction materials has been aggressively promoted by cement and concrete researchers in the last two decades. Besides being part of the concerted efforts to mitigate the negative environmental footprint of the construction industry, it’s also an opportunity to reduce the...

Repair of deteriorating concrete infrastructure remains a major challenge. The concern is that current repair materials are not able to prevent premature failure after a repair has been performed. Thus, an engineered repair mortar that can enhance the durability of repaired composites by mitigating moisture transport and its debilitating influence...

This paper describes results of several studies undertaken by the authors in the bid to valorize both Scrap Tire Polymeric Fiber (SPF) and Scrap Tire Steel Fiber (SSF) as value-added reinforcements in cement-based composites. Current scrap tire by-product management practices, fiber characteristics, and their influence on the plastic shrinkage crac...

In this study, experimental investigations were conducted on enhancing the crack-healing potential of concrete using the internal carbonation process. The objective is to overcome one major limitation of autogenous healing (limited carbonation) by using Sodium Carbonate (Na2CO3) solution as a healing agent. To replicate the different types of damag...

This study investigated the effect of CaCl2-blended acrylic polymer emulsion (CP) at 0%, 0.5%, 1.0%, and 1.5% by weight of cement on the degradation of alkali–silica reaction (ASR) susceptible fine aggregate particles. Mineralogical and textural characterizations of reactive aggregate particles were evaluated via X-ray diffraction (XRD) and scannin...

The disposal of copper mine tailings (CMT) in finite containment facilities near mine sites is a serious human safety and environmental management challenge in most copper-producing countries of the world. Therefore, this study evaluates the reuse potential of the CMT as a 0%–30% partial substitute material for cement in paste, mortar, and concrete...

This paper presents the results of a study on the effects of fine crumb rubber on the sulfate resistance of mortar mixtures. Mixtures with and without 10% silica fume (SF), containing 0%, 10% and 15% fine crumb rubber as a fine aggregate substitute material were subjected to sodium sulfate wet-dry cycles for two years. Changes in compressive streng...

Presently, scrap tire polymeric fibers (STF) have limited reuse value in most countries of the world, hence it is largely land filled or used as an eco-unfriendly tire derived fuel (TDF). Unfortunately, toxic gases and acids could be released from these aforementioned STF management strategies. Therefore, in this study, an alternative reuse approac...

Utilization of recyclates in the construction industry is hamstrung by perceptions of lower quality, uncertain performance benefits and high cost. Thus, in this study, the mechanical performance and cost implications of using scrap tire steel fiber (SSF) with a hitherto limited reuse value as a partial or full substitute for virgin commercial macro...

Although acrylic polymer emulsions have been reported to impart many desirable attributes to cement mortar; delayed hydration, excessive air entrapment and moisture induced loss of strength have been highlighted as constraints. This paper explores the utilization of hydrated calcium chloride blended-acrylic polymer emulsion (CP) as a mitigation mea...

Noninvasive ways of condition assessment and quality control during construction are critically needed. In the study reported here, the possibility of using the infrared thermography (IRT) technique to estimate the total porosity and the compressive strength of cement mortar was investigated. To assess the cooling characteristics of specimens and t...

In this study, cement-based application for polymeric scrap tire fibers (STF) which are hitherto used either as tire derived fuel or are disposed in landfills is explored. STF was characterized; surface morphology, organic and elemental composition of STF/crumb rubber inclusions were examined. Alkaline stability of the STF, the effects of STF on pl...

n this study, the mechanical strength, total porosity and corrosion performance of ordinary Port- land cement (OPC), class F fly ash (PFA) and metakaolin (MK) alkali-activated mortars (AAM) reinforced with 1 and 2% mass fraction of scrap tire steel fibers (SSF) were investigated. The accelerated corrosion test comprised of immersion of specimens in...

Poor crumb rubber-cement matrix interface contributes to the reduction in mechanical strength observed in cement composites containing recycled scrap tires as fine aggregate. In this paper, the efficacy of a two-stage approach of using limestone powder (LP) pre-coated crumb rubber and silica fume (SF) to enhance the performance of rubberized cement...

Increasing demands for copper and copper allied products have made the processing of low grade ores with high volume waste output unavoidable. Presently, billions of tons of copper tailings can be found in major copper producing countries. The impact of copper tailings at 0%, 5% and 10% addition level by mass of cement on the fresh and hardened pro...

The effects of copper tailings as an additive, on some durability properties of cement mixtures were investigated. In each mixture, copper tailings addition levels by mass were 0%, 5% and 10%. Compared to the control samples, copper tailings blended pastes showed superior performance against autoclave expansion while insignificant decreases in sulf...

This paper reports the results of research investigating the impact of copper tailings on some durability properties of cement pastes, mortars and concretes. Four mixtures incorporating copper tailings at 0% to 15% cement substitution levels by mass were used. Minor reductions in sulfate resistance of mortars and improved performance against autocl...

This paper presents the results of a study investigating the consistency, hardened and toxic metal immobilization properties of concretes containing copper tailings as an additive. To compare the effects of copper tailings on strength and strength related properties across two concrete classes, two series of concretes with 0.57 and 0.50 water-to-bi...

This paper investigates the suitability of copper tailings as a cement replacement material in mortars. The impact of copper tailings at 0%, 5%, 10% and 15% cement replacement level by mass on the rheology, mechanical and durability properties of mortars was evaluated. Results revealed higher yield stress and flow loss in mixtures incorporating cop...