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Full-Text Articles in Civil Engineering

Mechanical And Durability Properties Of Fly Ash Geopolymer Concrete – A Review, Ali Shebli, Jamal Khatib, Adel Elkordi Jun 2023

Mechanical And Durability Properties Of Fly Ash Geopolymer Concrete – A Review, Ali Shebli, Jamal Khatib, Adel Elkordi

BAU Journal - Science and Technology

Geopolymers have emerged as a promising alternative for Ordinary portland cement (OPC) in construction industry, due to their potential to minimize the emissions of carbon dioxide (CO2) and improve the efficiency of waste recycling. This paper aims to study the fresh and hardened properties of fly ash geopolymer concrete (GPC), as well as to review the raw materials used in the production of geopolymers. Several factors impact the mechanical and durability properties of fly ash GPC, including the specific type of fly ash utilized, the curing temperature, the alkaline activator (AA) concentration, and the type of AA used. …


The Effects Of Curing Temperature On The Hydration Kinetics Of Plain And Fly Ash Pastes And Compressive Strength Of Corresponding Mortars With And Without Nano-Tio2 Addition., Dan Huang, Mirian Velay-Lizancos, Jan Olek Jul 2022

The Effects Of Curing Temperature On The Hydration Kinetics Of Plain And Fly Ash Pastes And Compressive Strength Of Corresponding Mortars With And Without Nano-Tio2 Addition., Dan Huang, Mirian Velay-Lizancos, Jan Olek

International Conference on Durability of Concrete Structures

Incorporation of fly ash in cementitious systems containing ordinary portland cement (OPC) increases their long-term strength and durability. However, replacement of cement by fly ash also reduces the heat of hydration of such systems and reduces early-age strength development. The reduced rate of strength development can increase the risk of durability problems, e.g. scaling, in cases when young concrete is exposed to low temperatures and deicing chemicals. This study investigated the potential of nano-titanium dioxide (nano-TiO2) particles to modify the hydration kinetics of fly ash pastes and compressive strength development of corresponding mortars cured under low (4°C) and …


Mechanical Behavior Of Clay Soil Stabilized With Fly Ash And Bottom Ash, Soewignjo Agus Nugroho, Azra Zulnasari, Ferry Fatnanta, Andius Dasa Putra Apr 2022

Mechanical Behavior Of Clay Soil Stabilized With Fly Ash And Bottom Ash, Soewignjo Agus Nugroho, Azra Zulnasari, Ferry Fatnanta, Andius Dasa Putra

Makara Journal of Technology

Soil is one of the most important aspects of an infrastructure given its functions of receiving and holding structural loads. However, not all soils have good physical and mechanical properties. To overcome those conditions, stabilization of the soil is practiced to meet the technical requirements. This study aims to determine the behavior of high plasticity clay stabilized with lime, fly ash, and bottom ash. These additives can be used as a stabilizing agent to increase soil strength. The percentage of additives varied from 5%–25% then mixed with clay and were tested through the (Unconfined Compression Strength (UCS) test. The UCS …


The Influence Of Waste Glass Powder On The Chloride Binding Capacity Of Fly Ash/Cement Hardened Paste, Jh Yan, Tingyu Hao Nov 2019

The Influence Of Waste Glass Powder On The Chloride Binding Capacity Of Fly Ash/Cement Hardened Paste, Jh Yan, Tingyu Hao

International Conference on Durability of Concrete Structures

The potential of using waste glass powder to increase the chloride binding capacity of fly ash/cement hardened paste was investigated. When only fly ash replacing cement, the chloride binding capacity was raised within 28d when the fly ash replacement level was in the range from 30-50% by mass. But at a longer age of 60 to 90d, the binding performance was increased at the replacement level of 10-30wt%. The chloride binding capacity of glass powder-fly ash-cement system was increased by adding glass powder of 2% and 4% by mass at 7d while those at larger addition and longer age reduced. …


Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi Dec 2015

Effect Of Fly Ash Fortification In The Manufacture Process Of Making Concrete Towards Characteristics Of Concrete In Sulfuric Acid Solution, Asep Handaya Saputra, Muhammad Shohibi, Masatoshi Kubouchi

Makara Journal of Technology

Fly ash is a silica or alumino silica material that can be used as a constituent of cement in the concrete manufacturing process. Utilization of fly ash aims to improve durability and minimize the reduction of concrete’s compressive strength exposed to an acidic environment, which can be achieved through the pozzolanic reaction of fly ash with Ca(OH)2 within concrete. The reduced content of Ca(OH)2 through pozzolanic reaction will minimize the tendency of ettringite formation (compounds that cause deterioration and decrease the compressive strength of concrete). In order to determine the relation between fly ash replenishment into concrete with concrete’s characteristics …


High Strength Steel Fiber Reinforced Flow-Able Or Scc Concrete With Variable Fiber By Volume Fractions For Thin Plate And Shell Structures, Abebe Berhe Dec 2014

High Strength Steel Fiber Reinforced Flow-Able Or Scc Concrete With Variable Fiber By Volume Fractions For Thin Plate And Shell Structures, Abebe Berhe

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study is to incorporate discrete, short, mechanically deformed, small diameter steel fibers into high strength concrete with f'c > 70 MPa (10 ksi) in an attempt to reduce and partially eliminate the need for steel rebar in concrete construction. By introducing steel fibers to high strength concrete mixture, the overall tensile, compressive and shear strength of the mixture can be improved immensely thus, replacing portions or major parts of the longitudinal, temperature and shrinkage reinforcements. The reduction or elimination of longitudinal and transverse reinforcements in the construction of structural or non-structural members can result in savings in …


Surface Treatment Of Fly Ash For Improving The Tensile Strength Of Fly Ash/Unsaturated Polyester Composites, Sugiman Sugiman, Paryanto Dwi Setyawan Dec 2013

Surface Treatment Of Fly Ash For Improving The Tensile Strength Of Fly Ash/Unsaturated Polyester Composites, Sugiman Sugiman, Paryanto Dwi Setyawan

Makara Journal of Technology

The paper presents the surface treatment of fly ashes using acid and alkali solution on the tensile strength of the fly ash/unsaturated polyester (UP) composites. Sulfuric acid (H2SO4), hydrofluoric acid (HF) and sodium hydroxide (NaOH) solution with concentration of 0%, 5%, 10%, 15%, and 20% (by weight) were used for surface treatment of fly ashes. Generally, the tensile strength of the treated fly-ash/UP composites shows a significant increase compared to the untreated fly ash. Of all surface treatments studied, the optimum tensile strength was obtained at a concentration of 10%. At this concentration, at a fly ash content of 30% …


Development Of Approximating Functions To Model And Predict The Properties Of Fresh And Hardened Fly Ash-Based Geopolymer Concrete, Eleazar Ivan Diaz Loya Apr 2011

Development Of Approximating Functions To Model And Predict The Properties Of Fresh And Hardened Fly Ash-Based Geopolymer Concrete, Eleazar Ivan Diaz Loya

Doctoral Dissertations

The manuscript presented herein is based on the investigation of the mechanical properties of fly ash-based geopolymer concrete and their link to fly ash (FA) characteristics. A database of 32 FA samples was created. Each FA sample was analyzed in terms of chemical composition, crystallographic properties and particle size distribution. The mechanical performance of geopolymer concrete (GPC) made from each FA sample was evaluated in terms of density, setting time, compressive and flexural strength, static elastic modulus and Poisson's ratio. It is worth mentioning that the author has already published preliminary results of this study (Diaz and Allouche, 2010; Diaz …