This page has only limited features, please log in for full access.

Prof. Togay Ozbakkaloglu
Ingram School of Engineering, Texas State University, TX 78666, United States

Basic Info


Research Keywords & Expertise

0 Structural Engineering
0 geopolymers
0 Construction materials
0 biocomposites
0 Fiber Reinforced Polymers (FRPs)

Fingerprints

Structural applications of composites
geopolymers
Fiber Reinforced Polymers (FRPs)
green composites
Construction materials
Waste-based concretes
Composites incorporating recycled materials

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 14 August 2021 in Composite Structures
Reads 0
Downloads 0

This paper presents an experimental study on the impact performance of concrete columns confined with large-rupture-strain (LRS, rupture strain≥5%) fiber reinforced polymer (FRP) jackets. A total of 32 concrete specimens were prepared and tested using large-capacity drop-weight equipment. The test variables included four impact height (2, 3, 4 and 5 m), types of FRP, i.e., AFRP, polyethylene naphthalate (PEN) FRP and polyethylene terephthalate (PET) FRP and layers of FRP (1 and 2). The time histories of impact force and FRP rupture strain as well as failure modes were obtained from the test. Compared to the AFRP-confined concrete specimen with similar jacket stiffness, the core concrete of the LRS FRP-confined specimen was less damaged due to the large rupture strain characteristic. The impact force increased and the impact duration decreased with increasing impact height. The impact duration of specimens confined with LRS FRP was longer than that of the AFRP-confined concrete. Results showed that the impact-resistance behaviours of LRS FRP-confined concrete column outperformed its companion column confined with AFRP. Besides, increasing the thickness of FRP jacket can enhance the impact resistance capacity. These findings may facilitate the impact resistance strengthening/retrofitting of RC structures with the application of LRS FRP composites.

ACS Style

Zhi-Wei Yan; Yu-Lei Bai; Togay Ozbakkaloglu; Wan-Yang Gao; Jun-Jie Zeng. Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders. Composite Structures 2021, 276, 114563 .

AMA Style

Zhi-Wei Yan, Yu-Lei Bai, Togay Ozbakkaloglu, Wan-Yang Gao, Jun-Jie Zeng. Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders. Composite Structures. 2021; 276 ():114563.

Chicago/Turabian Style

Zhi-Wei Yan; Yu-Lei Bai; Togay Ozbakkaloglu; Wan-Yang Gao; Jun-Jie Zeng. 2021. "Axial impact behavior of Large-Rupture-Strain (LRS) fiber reinforced polymer (FRP)-confined concrete cylinders." Composite Structures 276, no. : 114563.

Short communication
Published: 13 August 2021 in Case Studies in Construction Materials
Reads 0
Downloads 0

Glass Fibre Reinforced Polymer (GFRP) composite wrap has become an effective repair system for deteriorated structural columns. It is essential to provide an infill material in the gap between the retrofitted column and the GFRP wrap. So, the properties of the infill material can significantly influence the contribution of these wraps and thus, can affect the overall performance of the retrofitted structure. However, the research on the effect of GFRP confinement on infill materials with various properties is still limited. This study explores the effectiveness of the GFRP wrapping system and its contribution to the axial compression behaviour of concrete, grout and epoxy infill materials. A total of 18 unconfined and GFRP-wrapped cylindrical columns were cast and tested under concentric axial compression loading. A finite element (FE) modelling was implemented using ABAQUS software to analyse the compression behaviour of GFRP-wrapped infill materials. The experimental results demonstrated that the confinement effect of the GFRP wrapping system is highly influenced by the properties of the infill material. The compressive strength and modulus of elasticity significantly increased due to GFRP wrapping by 149% and 77%, respectively for concrete infill, and by 40 % and 72 %, respectively for grout infill whereas negligible confinement efficiency observed in wrapped epoxy infill. The FE analyses showed a good correlation with the experimental results in predicting the overall compressive behaviour of the various infill materials. This study demonstrates valuable insights on the confinement effect of GFRP wraps in the repair of columns involving infill materials which therefore could be employed to better understand the overall behaviour of columns retrofitted with GFRP wrapping systems.

ACS Style

Omar F. Otoom; Weena Lokuge; Warna Karunasena; Allan C. Manalo; Togay Ozbakkaloglu; David Thambiratnam. Experimental and numerical evaluation of the compression behaviour of GFRP-wrapped infill materials. Case Studies in Construction Materials 2021, 15, e00654 .

AMA Style

Omar F. Otoom, Weena Lokuge, Warna Karunasena, Allan C. Manalo, Togay Ozbakkaloglu, David Thambiratnam. Experimental and numerical evaluation of the compression behaviour of GFRP-wrapped infill materials. Case Studies in Construction Materials. 2021; 15 ():e00654.

Chicago/Turabian Style

Omar F. Otoom; Weena Lokuge; Warna Karunasena; Allan C. Manalo; Togay Ozbakkaloglu; David Thambiratnam. 2021. "Experimental and numerical evaluation of the compression behaviour of GFRP-wrapped infill materials." Case Studies in Construction Materials 15, no. : e00654.

Review
Published: 30 July 2021 in Materials
Reads 0
Downloads 0

Development of sustainable concrete as an alternative to conventional concrete helps in reducing carbon dioxide footprint associated with the use of cement and disposal of waste materials in landfill. One way to achieve that is the use of fly ash (FA) as an alternative to ordinary Portland cement (OPC) because FA is a pozzolanic material and has a high amount of alumina and silica content. Because of its excellent mechanical properties, several studies have been conducted to investigate the use of alkali-activated FA-based concrete as an alternative to conventional concrete. FA, as an industrial by-product, occupies land, thereby causing environmental pollution and health problems. FA-based concrete has numerous advantages, such as it has early strength gaining, it uses low natural resources, and it can be configurated into different structural elements. This study initially presents a review of the classifications, sources, chemical composition, curing regimes and clean production of FA. Then, physical, fresh, and mechanical properties of FA-based concretes are studied. This review helps in better understanding of the behavior of FA-based concrete as a sustainable and eco-friendly material used in construction and building industries.

ACS Style

Mugahed Amran; Roman Fediuk; Gunasekaran Murali; Siva Avudaiappan; Togay Ozbakkaloglu; Nikolai Vatin; Maria Karelina; Sergey Klyuev; Aliakbar Gholampour. Fly Ash-Based Eco-Efficient Concretes: A Comprehensive Review of the Short-Term Properties. Materials 2021, 14, 4264 .

AMA Style

Mugahed Amran, Roman Fediuk, Gunasekaran Murali, Siva Avudaiappan, Togay Ozbakkaloglu, Nikolai Vatin, Maria Karelina, Sergey Klyuev, Aliakbar Gholampour. Fly Ash-Based Eco-Efficient Concretes: A Comprehensive Review of the Short-Term Properties. Materials. 2021; 14 (15):4264.

Chicago/Turabian Style

Mugahed Amran; Roman Fediuk; Gunasekaran Murali; Siva Avudaiappan; Togay Ozbakkaloglu; Nikolai Vatin; Maria Karelina; Sergey Klyuev; Aliakbar Gholampour. 2021. "Fly Ash-Based Eco-Efficient Concretes: A Comprehensive Review of the Short-Term Properties." Materials 14, no. 15: 4264.

Journal article
Published: 16 July 2021 in Journal of Building Engineering
Reads 0
Downloads 0

To reduce reinforcement congestion in locations of high rebar concentration in a structure, fiber-reinforced polymer (FRP) rebar (replacing steel rebar) can be used in combination with steel fiber (replacing stirrups). Here, an extensive investigation was conducted for the first time in literature on the effect of steel fibers and crumb rubber (CR) aggregate on the shear behavior of high-strength concrete beams reinforced with glass FRP (GFRP) bars. Thirty beam specimens were manufactured and the effect of the key variables including the GFRP reinforcement ratio, shear span-to-depth ratio, CR content, and fiber content in volume on the shear performance of the beams was investigated. Parameters under investigation were the cracking pattern, manner of failure, load-midspan deflection performance, shear capacity, toughness, and post-cracking strength of the beams. The results indicate that when the fiber volume fraction, concrete compressive strength, and GFRP reinforcement ratio increased, the beam shear capacity increased. Conversely, increasing the shear span-to-depth ratio and CR content led to a decrease in the shear capacity. It was also found that the steel fibers were more efficient in improving the beam shear behavior at higher content of CR, such that they changed the cracking type and failure mode from shear to flexural. Finally, the analysis of variance (ANOVA) technique was used to perform statistical analysis of experimental data and calculate the contribution of different parameters to the experimental results.

ACS Style

Mahdi Nematzadeh; Seyyed-Asgar Hosseini; Togay Ozbakkaloglu. The combined effect of crumb rubber aggregates and steel fibers on shear behavior of GFRP bar-reinforced high-strength concrete beams. Journal of Building Engineering 2021, 44, 102981 .

AMA Style

Mahdi Nematzadeh, Seyyed-Asgar Hosseini, Togay Ozbakkaloglu. The combined effect of crumb rubber aggregates and steel fibers on shear behavior of GFRP bar-reinforced high-strength concrete beams. Journal of Building Engineering. 2021; 44 ():102981.

Chicago/Turabian Style

Mahdi Nematzadeh; Seyyed-Asgar Hosseini; Togay Ozbakkaloglu. 2021. "The combined effect of crumb rubber aggregates and steel fibers on shear behavior of GFRP bar-reinforced high-strength concrete beams." Journal of Building Engineering 44, no. : 102981.

Review
Published: 17 June 2021 in Crystals
Reads 0
Downloads 0

Currently, a number of disadvantages hampers the use of recycled concrete aggregates (RCA). The current review proves that concretes made with complete replacement of natural aggregate with RCA allow the production of high-quality concrete. One of the possibilities for improving concrete properties with RCA is the use of extended curing and pozzolanic materials with varying cement ratios. The potential use of RCA concretes is in the production of high-value materials that increase environmental and financial benefits. RCA have strong potential in the development of a new generation of concrete and stimulate economic activity in many countries in addition to optimizing natural resources. Economic benefits include minimal travel costs; cheaper sources of concrete than newly mined aggregates; reduction of the landfill area required for the placement of concrete waste; the use of RCA minimizes the need for gravel extraction, etc. The proposed strategy could be to sequentially separate demolition waste such as roof finishes, waterproof materials, interior and exterior materials, etc. Closing life cycles is the main approach used for efficient structures for the recycling and reuse of construction and demolition waste in the production and recovery of materials, especially when recycling and reusing materials. In the life cycle, the recycling of recovered materials allows them to be used for new construction purposes, avoiding the use of natural concrete aggregates. Government, design institutes, construction departments and project managers should be involved in the creation and use of RCA. In demolition and construction, the main players are the project owners. Their obligations, expectations and responsibilities must be properly aligned. For the past 20 years, recycled concrete aggregate from demolition and construction waste has been considered as an alternative to pure concrete in structural concrete to minimize the environmental impact of construction waste and demolition waste and the conversion of natural aggregate resources. It is now recognized that the use of RCA for the generations of concrete is a promising and very attractive technology for reducing the environmental impact of the construction sector and conserving natural resources. In the market, the selling price is not an obstacle for market applications of RCA, as there are scenarios in which their cost is lower than the cost of products made from conventional building materials. This is more of an acceptance factor in the market for recycled concrete aggregates. In this sector, the lack of identification, accreditation and uniform quality certification systems and their narrow application cause some marketing problems. With proper RCA preparation, concrete with standard physical and mechanical properties and performance characteristics can be obtained.

ACS Style

Natt Makul; Roman Fediuk; Mugahed Amran; Abdullah Zeyad; Sergey Klyuev; Irina Chulkova; Togay Ozbakkaloglu; Nikolai Vatin; Maria Karelina; Afonso Azevedo. Design Strategy for Recycled Aggregate Concrete: A Review of Status and Future Perspectives. Crystals 2021, 11, 695 .

AMA Style

Natt Makul, Roman Fediuk, Mugahed Amran, Abdullah Zeyad, Sergey Klyuev, Irina Chulkova, Togay Ozbakkaloglu, Nikolai Vatin, Maria Karelina, Afonso Azevedo. Design Strategy for Recycled Aggregate Concrete: A Review of Status and Future Perspectives. Crystals. 2021; 11 (6):695.

Chicago/Turabian Style

Natt Makul; Roman Fediuk; Mugahed Amran; Abdullah Zeyad; Sergey Klyuev; Irina Chulkova; Togay Ozbakkaloglu; Nikolai Vatin; Maria Karelina; Afonso Azevedo. 2021. "Design Strategy for Recycled Aggregate Concrete: A Review of Status and Future Perspectives." Crystals 11, no. 6: 695.

Journal article
Published: 29 May 2021 in Composite Structures
Reads 0
Downloads 0

The polyethylene naphthalene (PEN) and polyethylene terephthalate (PET) fibers have a tensile rupture strain of over 5%, and hence they are referred to as large-rupture-strain (LRS) fiber reinforced polymer (FRP) materials. Their large rupture strain characteristics may contribute to significant improvement of the impact resistance of reinforced concrete (RC) structures. This study investigates the strain rate effect on LRS FRP-confined concrete through Split Hopkinson Pressure Bar (SHPB) test. Results revealed that LRS FRP-confined concrete specimens exhibited superior impact resistance behaviors compared to the counterpart confined with CFRP composites when subjected to a single impact. The critical strain, compressive strength and toughness of the LRS FRP-confined concrete specimen increased with increasing strain rate. Due to the large rupture strain characteristics, the LRS FRP-confined concrete specimen virtually had no visible damage after a single impact. To study the damage evolution mechanism of concrete, the specimens were impacted for multiple times with the same energy until the failure of the specimen. Due to progressive concrete damage, the dynamic compressive strength and toughness experienced a decrease during multiple impacts. These findings might promote the application of LRS FRP materials in the field of impact resistance design of RC structures as a promising external jacketing material.

ACS Style

Zhi-Wei Yan; Yu-Lei Bai; Togay Ozbakkaloglu; Wan-Yang Gao; Jun-Jie Zeng. Rate-Dependent Compressive Behavior of Concrete Confined with Large-Rupture-Strain (LRS) FRP. Composite Structures 2021, 272, 114199 .

AMA Style

Zhi-Wei Yan, Yu-Lei Bai, Togay Ozbakkaloglu, Wan-Yang Gao, Jun-Jie Zeng. Rate-Dependent Compressive Behavior of Concrete Confined with Large-Rupture-Strain (LRS) FRP. Composite Structures. 2021; 272 ():114199.

Chicago/Turabian Style

Zhi-Wei Yan; Yu-Lei Bai; Togay Ozbakkaloglu; Wan-Yang Gao; Jun-Jie Zeng. 2021. "Rate-Dependent Compressive Behavior of Concrete Confined with Large-Rupture-Strain (LRS) FRP." Composite Structures 272, no. : 114199.

Technical paper
Published: 26 May 2021 in Structural Concrete
Reads 0
Downloads 0

The focus of this study is to investigate the effect of using coarse recycled concrete aggregates (RCAs) as an alternative material to natural coarse aggregate on the fresh, mechanical and durability behavior of concrete reinforced with steel fiber. Eighteen unique concrete mixes with RCA content of 0%, 50%, and 100% and steel fiber content of 0%, 1%, and 2% were prepared, and tests were performed to study slump, density, compressive and splitting tensile strengths, flexural behavior, surface hardness, surface abrasion resistance, water absorption, and sorptivity of each mix. It is shown that concrete containing RCA has a lower unit weight, compressive, splitting tensile and flexural strength, flexural toughness, surface hardness, and abrasion resistance, and a higher water absorption and sorptivity in comparison with conventional concrete. An increased compressive, splitting tensile and flexural strength, flexural toughness, surface hardness, and abrasion resistance, and a decreased water absorption and sorptivity of concrete with an increased steel fiber content from 1% to 2% is less significant compared to those from 0% to 1%. The results also show that, at RCA content of 50%, incorporating 1% steel fiber develops a concrete mix with similar or even better properties compared to unreinforced conventional concrete. At 100% RCA content, incorporating 2% steel fiber develops a concrete mix with similar properties to unreinforced conventional concrete having water to cement ratio of 0.3, but inferior properties to unreinforced conventional concrete having water to cement ratio of 0.5. These findings indicate that recycled aggregate concrete with similar or even better properties compared to concrete with natural aggregate can be developed through properly designing mixes, providing a great avenue toward the production of green construction material for structural applications.

ACS Style

Gokhan Kaplan; Oguzhan Yavuz Bayraktar; Aliakbar Gholampour; Osman Gencel; Fuat Koksal; Togay Ozbakkaloglu. Mechanical and durability properties of steel fiber‐reinforced concrete containing coarse recycled concrete aggregate. Structural Concrete 2021, 1 .

AMA Style

Gokhan Kaplan, Oguzhan Yavuz Bayraktar, Aliakbar Gholampour, Osman Gencel, Fuat Koksal, Togay Ozbakkaloglu. Mechanical and durability properties of steel fiber‐reinforced concrete containing coarse recycled concrete aggregate. Structural Concrete. 2021; ():1.

Chicago/Turabian Style

Gokhan Kaplan; Oguzhan Yavuz Bayraktar; Aliakbar Gholampour; Osman Gencel; Fuat Koksal; Togay Ozbakkaloglu. 2021. "Mechanical and durability properties of steel fiber‐reinforced concrete containing coarse recycled concrete aggregate." Structural Concrete , no. : 1.

Original research paper
Published: 20 May 2021 in International Journal of Pavement Research and Technology
Reads 0
Downloads 0

Stockpiles of discarded tires are a global concern. Since tire incinerating results in severe air pollution, reusing tires as tire rubber particles can reduce environmental pollution. A recycled tire, including rubber and recycled steel fiber, can be introduced in cement concrete. This study aimed to investigate the effects of crumb rubber and recycled steel fiber on the conventional concrete pavement's short- and long-term performance. The impact of crumb rubber (Cr) (0–20%) and recycled steel fiber (F) (0–0.5%) on the compressive, splitting, and flexural strength, as well as abrasion and freezing–thawing resistance of concrete, was evaluated through response surface methodology (RSM). The results indicated that fiber's addition to the concrete mix had a remarkable influence on flexural strength in low content and enhanced post-cracking ductility of rubberized concrete. Furthermore, incorporating crumb rubber as fine aggregate led to a reduction in the abrasion resistance and increased sensitivity to freezing–thawing in the presence of saline solution. According to optimization results, the most appropriate way to benefit from the desirable characteristics of rubberized concrete while minimizing the crumb rubber inclusion's adverse effects is through the addition of fibers into the concrete mixtures.

ACS Style

A. Zarei; H. Rooholamini; T. Ozbakkaloglu. Evaluating the Properties of Concrete Pavements Containing Crumb Rubber and Recycled Steel Fibers Using Response Surface Methodology. International Journal of Pavement Research and Technology 2021, 1 -15.

AMA Style

A. Zarei, H. Rooholamini, T. Ozbakkaloglu. Evaluating the Properties of Concrete Pavements Containing Crumb Rubber and Recycled Steel Fibers Using Response Surface Methodology. International Journal of Pavement Research and Technology. 2021; ():1-15.

Chicago/Turabian Style

A. Zarei; H. Rooholamini; T. Ozbakkaloglu. 2021. "Evaluating the Properties of Concrete Pavements Containing Crumb Rubber and Recycled Steel Fibers Using Response Surface Methodology." International Journal of Pavement Research and Technology , no. : 1-15.

Journal article
Published: 05 May 2021 in Materials
Reads 0
Downloads 0

Eco-friendly and sustainable materials that are cost-effective, while having a reduced carbon footprint and energy consumption, are in great demand by the construction industry worldwide. Accordingly, alkali-activated materials (AAM) composed primarily of industrial byproducts have emerged as more desirable alternatives to ordinary Portland cement (OPC)-based concrete. Hence, this study investigates the cradle-to-gate life-cycle assessment (LCA) of ternary blended alkali-activated mortars made with industrial byproducts. Moreover, the embodied energy (EE), which represents an important parameter in cradle-to-gate life-cycle analysis, was investigated for 42 AAM mixtures. The boundary of the cradle-to-gate system was extended to include the mechanical and durability properties of AAMs on the basis of performance criteria. Using the experimental test database thus developed, an optimized artificial neural network (ANN) combined with the cuckoo optimization algorithm (COA) was developed to estimate the CO2 emissions and EE of AAMs. Considering the lack of systematic research on the cradle-to-gate LCA of AAMs in the literature, the results of this research provide new insights into the assessment of the environmental impact of AAM made with industrial byproducts. The final weight and bias values of the AAN model can be used to design AAM mixtures with targeted mechanical properties and CO2 emission considering desired amounts of industrial byproduct utilization in the mixture.

ACS Style

Iman Faridmehr; Moncef Nehdi; Mehdi Nikoo; Ghasan Huseien; Togay Ozbakkaloglu. Life-Cycle Assessment of Alkali-Activated Materials Incorporating Industrial Byproducts. Materials 2021, 14, 2401 .

AMA Style

Iman Faridmehr, Moncef Nehdi, Mehdi Nikoo, Ghasan Huseien, Togay Ozbakkaloglu. Life-Cycle Assessment of Alkali-Activated Materials Incorporating Industrial Byproducts. Materials. 2021; 14 (9):2401.

Chicago/Turabian Style

Iman Faridmehr; Moncef Nehdi; Mehdi Nikoo; Ghasan Huseien; Togay Ozbakkaloglu. 2021. "Life-Cycle Assessment of Alkali-Activated Materials Incorporating Industrial Byproducts." Materials 14, no. 9: 2401.

Journal article
Published: 11 March 2021 in Construction and Building Materials
Reads 0
Downloads 0

The growing production of industrial by-products, such as fly ash (FA), ground granulated blast furnace slag (GGBS), and lead smelter slag (LSS), has resulted in significant negative impacts on the environment. Meanwhile, the high demand for ordinary Portland cement (OPC) and the over-exploitation of natural sand (NS) has also negatively impacted the ecosystem. The use of the mentioned industrial by-products to replace OPC and NS offers great potential for reducing the environmental impact of both the industrial wastes and conventional concrete. This study investigates the possible improvements to mechanical and durability properties of combined FA and GGBS-based alkali-activated binder (AAB) mortars prepared with NS and LSS sands through the addition of graphene oxide (GO). The results show that the increase of GGBS content in the binder of AAB composites (i.e. 20% and 50% GGBS) results in a significant increase in compressive and tensile strengths, and a decrease in drying shrinkage, flowability, and water absorption of the mortars. It is found that mortars with 0.05% and 0.1% GO additives provide better mechanical and durability properties than the control mortars. The study also shows that oxygen functional groups of GO sheets have been reduced in alkaline solution, and they were turned into the form of reduced graphene oxide (rGO) sheets with a higher wrinkling degree in their shapes. The better performance of AAB mortars containing GO additives is attributed to the improvement of the gel matrix formed through the combination of chemical and mechanical interactions between rGO sheets and the gel products. The outcomes of this study point to the great potential of the combined use of waste materials and GO additives to enhance the performance of AAB composites.

ACS Style

Van Dac Ho; Aliakbar Gholampour; Dusan Losic; Togay Ozbakkaloglu. Enhancing the performance and environmental impact of alkali-activated binder-based composites containing graphene oxide and industrial by-products. Construction and Building Materials 2021, 284, 122811 .

AMA Style

Van Dac Ho, Aliakbar Gholampour, Dusan Losic, Togay Ozbakkaloglu. Enhancing the performance and environmental impact of alkali-activated binder-based composites containing graphene oxide and industrial by-products. Construction and Building Materials. 2021; 284 ():122811.

Chicago/Turabian Style

Van Dac Ho; Aliakbar Gholampour; Dusan Losic; Togay Ozbakkaloglu. 2021. "Enhancing the performance and environmental impact of alkali-activated binder-based composites containing graphene oxide and industrial by-products." Construction and Building Materials 284, no. : 122811.

Erratum
Published: 09 March 2021 in Construction and Building Materials
Reads 0
Downloads 0
ACS Style

L. Gu; T. Ozbakkaloglu; A. Fallah Pour. Corrigendum to “Normal- and high-strength concretes incorporating air-cooled blast furnace slag coarse aggregates: Effect of slag size and content on the behavior” [Constr. Build. Mater. 126 (2016) 138–146]. Construction and Building Materials 2021, 278, 122931 .

AMA Style

L. Gu, T. Ozbakkaloglu, A. Fallah Pour. Corrigendum to “Normal- and high-strength concretes incorporating air-cooled blast furnace slag coarse aggregates: Effect of slag size and content on the behavior” [Constr. Build. Mater. 126 (2016) 138–146]. Construction and Building Materials. 2021; 278 ():122931.

Chicago/Turabian Style

L. Gu; T. Ozbakkaloglu; A. Fallah Pour. 2021. "Corrigendum to “Normal- and high-strength concretes incorporating air-cooled blast furnace slag coarse aggregates: Effect of slag size and content on the behavior” [Constr. Build. Mater. 126 (2016) 138–146]." Construction and Building Materials 278, no. : 122931.

Erratum
Published: 09 March 2021 in Construction and Building Materials
Reads 0
Downloads 0
ACS Style

A. Gholampour; A.H. Gandomi; T. Ozbakkaloglu; T. Xie. Corrigendum to “New formulations for mechanical properties of recycled aggregate concrete using gene expression programming” [Constr. Build. Mater. 130 (2017) 122–145]. Construction and Building Materials 2021, 278, 122930 .

AMA Style

A. Gholampour, A.H. Gandomi, T. Ozbakkaloglu, T. Xie. Corrigendum to “New formulations for mechanical properties of recycled aggregate concrete using gene expression programming” [Constr. Build. Mater. 130 (2017) 122–145]. Construction and Building Materials. 2021; 278 ():122930.

Chicago/Turabian Style

A. Gholampour; A.H. Gandomi; T. Ozbakkaloglu; T. Xie. 2021. "Corrigendum to “New formulations for mechanical properties of recycled aggregate concrete using gene expression programming” [Constr. Build. Mater. 130 (2017) 122–145]." Construction and Building Materials 278, no. : 122930.

Journal article
Published: 05 March 2021 in Composite Structures
Reads 0
Downloads 0

This study presents the results of the first experimental research on the axial compressive behavior of ultra-high-strength steel (UHSS) fiber reinforced concrete-filled FRP tubes (UHSSFR-CFFT). 24 circular UHSSFR-CFFT specimens were prepared and tested under axial compression to study the influence of unconfined concrete strength and fiber type. CFFTs were manufactured with glass, carbon and basalt reinforced polymer (GFRP, CFRP and BFRP) tubes with concrete compressive strengths (f′co) ranging from 35 to 105 MPa. Axial and lateral behavior were examined closely, including variation of lateral behavior along height of specimen. The results showed that the influence of concrete compressive strength on axial compressive behavior of UHSSFR-CFFTs is dependent on fiber type. For a similar normalized lateral confining pressure of FRP jacket at ultimate (flu/f′co), axial stress enhancement ratios (k1) were observed to decrease with an increase in f′co for all three fiber types. On the other hand, the obtained axial strain enhancement ratios (k2) indicated that k2 is influenced more by flu/f′co than f′co. Comparison of the recorded values of k1 and k2 for UHSSFR-CFFT with FRP-confined plain concrete showed similar trends on the influence of (f′co) on k1, but an opposite trend was observed for k2 of BFRP-confined specimens of the current study, in which k2 increased with increasing f′co. The results showed that the shape of the lateral strain-to-axial strain curves for UHSSFR CFRP- and BFRP-confined concrete specimens were similar to those of FRP-confined plain concrete, and this relationship was not influenced noticeably by f′co. Conversely, the obtained shape of the lateral strain-to-axial strain curves for UHSSFR GFRP-confined specimens was noticeably different when compared to FRP-confined plain concrete, with this behavior influenced by f′co. Finally, the results indicated that the addition of UHSS fibers in CFRP-confined specimens did not alter the influence of f′co on strain reduction factor (kɛ) where a decrease was observed by increasing f′co. However, the converse outcome was observed for GFRP- and BFRP-confined specimens where an increase in kɛ was observed when increasing f′co.

ACS Style

Ali Fallah Pour; Togay Ozbakkaloglu; Thomas Vincent. Axial compressive behavior of ultra-high-strength steel fiber-reinforced concrete-filled fiber reinforced polymer (FRP) tube columns. Composite Structures 2021, 266, 113777 .

AMA Style

Ali Fallah Pour, Togay Ozbakkaloglu, Thomas Vincent. Axial compressive behavior of ultra-high-strength steel fiber-reinforced concrete-filled fiber reinforced polymer (FRP) tube columns. Composite Structures. 2021; 266 ():113777.

Chicago/Turabian Style

Ali Fallah Pour; Togay Ozbakkaloglu; Thomas Vincent. 2021. "Axial compressive behavior of ultra-high-strength steel fiber-reinforced concrete-filled fiber reinforced polymer (FRP) tube columns." Composite Structures 266, no. : 113777.

Review
Published: 26 February 2021 in Crystals
Reads 0
Downloads 0

Recycled concrete aggregates (RCA) are used in existing green building composites to promote the environmental preservation of natural coarse aggregates (NCA). Besides, the use of RCA leads to potential solutions to the social and economic problems caused by concrete waste. It is found that insufficient information on the longevity and sustainability of RCA production is a serious issue that requires close attention due to its impact on changing aspects of the sector. However, more attention has been paid to explaining the effect of RCA on concrete durability, as well as the properties of fresh and hardened concrete. Therefore, this study aims to provide a critical review on the RCAs for the production of high-performances concrete structures. It begins by reviewing the source, originality, types, prediction of service life, features and properties of RCA, as well as the effect of RCA on concrete performance. In addition, this literature review summarizes the research findings to produce complete insights into the potential applications of RCA as raw, renewable, and sustainable building materials for producing greener concrete composite towards industrializing ecofriendly buildings today. Further, it has also highlighted the differences in the current state of knowledge between RCAs and NCAs, and offers several future research suggestions. Through this critical and analytical study, it can be said that RCA has the possible use in the production of high-performance structural concrete depending on the source and type of recycled aggregate while the RCA can be used widely and safely to produce traditional green concrete.

ACS Style

Natt Makul; Roman Fediuk; Mugahed Amran; Abdullah Zeyad; Gunasekaran Murali; Nikolai Vatin; Sergey Klyuev; Togay Ozbakkaloglu; Yuriy Vasilev. Use of Recycled Concrete Aggregates in Production of Green Cement-Based Concrete Composites: A Review. Crystals 2021, 11, 232 .

AMA Style

Natt Makul, Roman Fediuk, Mugahed Amran, Abdullah Zeyad, Gunasekaran Murali, Nikolai Vatin, Sergey Klyuev, Togay Ozbakkaloglu, Yuriy Vasilev. Use of Recycled Concrete Aggregates in Production of Green Cement-Based Concrete Composites: A Review. Crystals. 2021; 11 (3):232.

Chicago/Turabian Style

Natt Makul; Roman Fediuk; Mugahed Amran; Abdullah Zeyad; Gunasekaran Murali; Nikolai Vatin; Sergey Klyuev; Togay Ozbakkaloglu; Yuriy Vasilev. 2021. "Use of Recycled Concrete Aggregates in Production of Green Cement-Based Concrete Composites: A Review." Crystals 11, no. 3: 232.

Journal article
Published: 22 February 2021 in Applied Sciences
Reads 0
Downloads 0

Increasing the thermal insulation of building components to reduce the thermal energy loss of buildings has received significant attention. Owing to its porous structure, using expanded vermiculite as an alternative to natural river sand in the development of building materials would result in improvement of the thermal performance of buildings. This study investigates the properties of fly ash (FA)-based geopolymer mortars prepared with expanded vermiculite. The main aim of this study was to produce geopolymer mortar with lower thermal conductivity than conventional mortar for thermal insulation applications in buildings. A total of twelve batches of geopolymers were prepared for evaluating their different properties. The obtained results show that, at a given FA and expanded vermiculite content, the geopolymers prepared with a 10 molar NaOH solution exhibited a higher flowability, water absorption and porosity, as well as a lower dry unit weight, compressive strength, ultrasound pulse velocity and thermal conductivity compared with those prepared with a 15 molar NaOH solution. As is also shown, the geopolymers containing expanded vermiculite (15%) developed a lower flowability (~6%), dry unit weight (~6%), compressive strength (~7%), ultrasound pulse velocity (~6%) and thermal conductivity (~18%), as well as a higher apparent porosity (~6%) and water absorption (~9%) compared with those without expanded vermiculite at a given FA content and NaOH concentration. The findings of this study suggest that incorporating expanded vermiculite in FA-based geopolymer mortar can provide eco-friendly and lightweight building composites with improved sound and thermal insulation properties, contributing toward the reduction of the environmental effects of waste materials and conservation of natural sand.

ACS Style

Osman Gencel; Aliakbar Gholampour; Hayrettin Tokay; Togay Ozbakkaloglu. Replacement of Natural Sand with Expanded Vermiculite in Fly Ash-Based Geopolymer Mortars. Applied Sciences 2021, 11, 1917 .

AMA Style

Osman Gencel, Aliakbar Gholampour, Hayrettin Tokay, Togay Ozbakkaloglu. Replacement of Natural Sand with Expanded Vermiculite in Fly Ash-Based Geopolymer Mortars. Applied Sciences. 2021; 11 (4):1917.

Chicago/Turabian Style

Osman Gencel; Aliakbar Gholampour; Hayrettin Tokay; Togay Ozbakkaloglu. 2021. "Replacement of Natural Sand with Expanded Vermiculite in Fly Ash-Based Geopolymer Mortars." Applied Sciences 11, no. 4: 1917.

Review
Published: 08 February 2021 in Crystals
Reads 0
Downloads 0

In the last few decades, the demand for cement production increased and caused a massive ecological issue by emitting 8% of the global CO2, as the making of 1 ton of ordinary Portland cement (OPC) emits almost a single ton of CO2. Significant air pollution and damage to human health are associated with the construction and cement industries. Consequently, environmentalists and governments have ordered to strongly control emission rates by using other ecofriendly supplemental cementing materials. Rice husk is a cultivated by-product material, obtained from the rice plant in enormous quantities. With no beneficial use, it is an organic waste material that causes dumping issues. Rice husk has a high silica content that makes it appropriate for use in OPC; burning it generates a high pozzolanic reactive rice husk ash (RHA) for renewable cement-based recyclable material. Using cost-effective and commonly obtainable RHA as mineral fillers in concrete brings plentiful advantages to the technical characteristics of concrete and to ensure a clean environment. With RHA, concrete composites that are robust, highly resistant to aggressive environments, sustainable and economically feasible can be produced. However, the production of sustainable and greener concrete composites also has become a key concern in the construction industries internationally. This article reviews the source, clean production, pozzolanic activity and chemical composition of RHA. This literature review also provides critical reviews on the properties, hardening conditions and behaviors of RHA-based concrete composites, in addition to summarizing the research recent findings, to ultimately produce complete insights into the possible applications of RHA as raw building materials for producing greener concrete composites—all towards industrializing ecofriendly buildings.

ACS Style

Mugahed Amran; Roman Fediuk; Gunasekaran Murali; Nikolai Vatin; Maria Karelina; Togay Ozbakkaloglu; R. S. Krishna; Ankit Kumar S.; Shaswat Kumar D.; Jyotirmoy Mishra. Rice Husk Ash-Based Concrete Composites: A Critical Review of Their Properties and Applications. Crystals 2021, 11, 168 .

AMA Style

Mugahed Amran, Roman Fediuk, Gunasekaran Murali, Nikolai Vatin, Maria Karelina, Togay Ozbakkaloglu, R. S. Krishna, Ankit Kumar S., Shaswat Kumar D., Jyotirmoy Mishra. Rice Husk Ash-Based Concrete Composites: A Critical Review of Their Properties and Applications. Crystals. 2021; 11 (2):168.

Chicago/Turabian Style

Mugahed Amran; Roman Fediuk; Gunasekaran Murali; Nikolai Vatin; Maria Karelina; Togay Ozbakkaloglu; R. S. Krishna; Ankit Kumar S.; Shaswat Kumar D.; Jyotirmoy Mishra. 2021. "Rice Husk Ash-Based Concrete Composites: A Critical Review of Their Properties and Applications." Crystals 11, no. 2: 168.

Journal article
Published: 29 January 2021 in Journal of Building Engineering
Reads 0
Downloads 0

This paper presents the first investigation on foam concretes with fly ash and fine recycled concrete aggregate (RFA). Foam concretes were produced considering 0, 25, 50, 75 and 100% RFA ratio instead of virgin sand. Tests were conducted to assess their porosity, density, compressive strength, dynamic elastic modulus, absorption, ultrasound and thermal characteristics. Scanning electron microscopy analyzes were performed for investigating the microstructure of concretes. Findings show that incorporating RFA results in slight rise in porosity and absorption while decrease in dynamic elastic modulus, ultrasound and thermal conductivity. Observations present an expectancy toward production of light-weight construction material contributing to significant environmental benefits.

ACS Style

Osman Gencel; Mirac Oguz; Aliakbar Gholampour; Togay Ozbakkaloglu. Recycling waste concretes as fine aggregate and fly ash as binder in production of thermal insulating foam concretes. Journal of Building Engineering 2021, 38, 102232 .

AMA Style

Osman Gencel, Mirac Oguz, Aliakbar Gholampour, Togay Ozbakkaloglu. Recycling waste concretes as fine aggregate and fly ash as binder in production of thermal insulating foam concretes. Journal of Building Engineering. 2021; 38 ():102232.

Chicago/Turabian Style

Osman Gencel; Mirac Oguz; Aliakbar Gholampour; Togay Ozbakkaloglu. 2021. "Recycling waste concretes as fine aggregate and fly ash as binder in production of thermal insulating foam concretes." Journal of Building Engineering 38, no. : 102232.

Review
Published: 14 January 2021 in Materials
Reads 0
Downloads 0

Concrete is the most common building material; therefore, when designing structures, it is obligatory to consider all structural parameters and design characteristics such as acoustic properties. In particular, this is to ensure comfortable living conditions for people in residential premises, including acoustic comfort. Different types of concrete behave differently as a sound conductor; especially dense mixtures are superior sound reflectors, and light ones are sound absorbers. It is found that the level of sound reflection in modified concrete is highly dependent on the type of aggregates, size and distribution of pores, and changes in concrete mix design constituents. The sound absorption of acoustic insulation concrete (AIC) can be improved by forming open pores in concrete matrices by either using a porous aggregate or foam agent. To this end, this article reviews the noise and sound transmission in buildings, types of acoustic insulating materials, and the AIC properties. This literature study also provides a critical review on the type of concretes, the acoustic insulation of buildings and their components, the assessment of sound insulation of structures, as well as synopsizes the research development trends to generate comprehensive insights into the potential applications of AIC as applicable material to mitigate noise pollution for increase productivity, health, and well-being.

ACS Style

Roman Fediuk; Mugahed Amran; Nikolai Vatin; Yuriy Vasilev; Valery Lesovik; Togay Ozbakkaloglu. Acoustic Properties of Innovative Concretes: A Review. Materials 2021, 14, 398 .

AMA Style

Roman Fediuk, Mugahed Amran, Nikolai Vatin, Yuriy Vasilev, Valery Lesovik, Togay Ozbakkaloglu. Acoustic Properties of Innovative Concretes: A Review. Materials. 2021; 14 (2):398.

Chicago/Turabian Style

Roman Fediuk; Mugahed Amran; Nikolai Vatin; Yuriy Vasilev; Valery Lesovik; Togay Ozbakkaloglu. 2021. "Acoustic Properties of Innovative Concretes: A Review." Materials 14, no. 2: 398.

Journal article
Published: 20 November 2020 in Sustainability
Reads 0
Downloads 0

Precast concrete elements provide a feasible way to expedite on-site construction; however, typical precast components are massive, making their use particularly undesirable at construction sites that suffer from low load-bearing capacity or have swelling soils. This research aims to develop an optimal lightweight expanded polystyrene foam concrete (EPS-foam concrete) slab through a consideration of various parameters. The precast EPS-foam concrete half-shaped slabs were prepared with a density and compressive strength of 1980 kg/m3 and 35 MPa, respectively. Quarry dust (QD) and EPS beads were utilized as substitutions for fine and coarse aggregates with replacement-levels that varied from 5% to 22.5% and 15% to 30%, respectively. The use of EPS beads revealed sufficient early age strength; at the same time, the utilization of quarry dust in EPS-foam concrete led to a more than 30% increase in compressive strength compared to the EPS-based mixtures. Two hundred and fifty-six trial mixes were produced to examine the physical and mechanical characteristics of EPS-foam concrete. Three batches of a total of four EPS-foam concrete half-shaped slabs with spans of 3.5 and 4.5 m and thicknesses of 200 and 250 mm were prepared. Findings showed that the ultimate shear forces for the full-scale EPS-foam concrete half-shaped slabs were approximately 6–12% lower than those of the identical concrete samples with a 2410 kg/m3 average density, and 26–32% higher than the theoretical predictions. Also, it was observed that the self-weight of EPS-foam concrete was reduced by up to 20% compared to the control mixtures. Findings revealed that the prepared precast EPS-foam concrete half-shaped slabs could possibly be applied as flooring elements in today’s modern infrastructure.

ACS Style

Sanusi Saheed; Farah Aziz; Mugahed Amran; Nikolai Vatin; Roman Fediuk; Togay Ozbakkaloglu; Gunasekaran Murali; Mohammad Mosaberpanah. Structural Performance of Shear Loaded Precast EPS-Foam Concrete Half-Shaped Slabs. Sustainability 2020, 12, 9679 .

AMA Style

Sanusi Saheed, Farah Aziz, Mugahed Amran, Nikolai Vatin, Roman Fediuk, Togay Ozbakkaloglu, Gunasekaran Murali, Mohammad Mosaberpanah. Structural Performance of Shear Loaded Precast EPS-Foam Concrete Half-Shaped Slabs. Sustainability. 2020; 12 (22):9679.

Chicago/Turabian Style

Sanusi Saheed; Farah Aziz; Mugahed Amran; Nikolai Vatin; Roman Fediuk; Togay Ozbakkaloglu; Gunasekaran Murali; Mohammad Mosaberpanah. 2020. "Structural Performance of Shear Loaded Precast EPS-Foam Concrete Half-Shaped Slabs." Sustainability 12, no. 22: 9679.

Journal article
Published: 10 November 2020 in Construction and Building Materials
Reads 0
Downloads 0

The newly developed waste-based concrete (WBC) is a viable eco-friendly and sustainable alternative to conventional concrete, which has the potential of decreasing the negative impact of concrete production on the eco-system. Therefore, understanding the behavior of WBCs in structural applications is important. To this effect, this paper presents the first study on the behavior of actively confined WBC under axial compression loading. Two batches of WBC containing ground granulated blast furnace slag (GGBS) as binder and recycled concrete aggregate as coarse aggregate obtained from construction & demolition (C&D) waste were manufactured using two fine aggregate types, namely glass sand (GS) and lead smelter slag (LSS). WBCs were confined at four confining pressures of 5, 10, 15 and 25 MPa using a Hoek cell, and tests were conducted for assessing the effect of the fine aggregate type and confinement level on the axial compressive behavior of WBCs. The results show that, at a given confining pressure, WBCs containing LSS exhibit higher strength and strain enhancement coefficients compared to WBCs containing GS, indicating that confinement is more effective in the former. The results also show that LSS concrete exhibits an axial stress–strain curve with a slightly less steep post-peak descending branch and slightly higher rate of lateral dilation for a given axial strain compared to GS concrete. The comparison between the predictions by an existing accurate model for conventional concrete and the experimental results of this study reveals that WBC containing LSS under active confinement exhibits similar stress and strain relationships to that of conventional concrete. These results are promising and point to the possibility of utilizing the newly developed WBC in structural columns with lateral confinement.

ACS Style

Aliakbar Gholampour; Togay Ozbakkaloglu; Osman Gencel; Tuan D. Ngo. Concretes containing waste-based materials under active confinement. Construction and Building Materials 2020, 270, 121465 .

AMA Style

Aliakbar Gholampour, Togay Ozbakkaloglu, Osman Gencel, Tuan D. Ngo. Concretes containing waste-based materials under active confinement. Construction and Building Materials. 2020; 270 ():121465.

Chicago/Turabian Style

Aliakbar Gholampour; Togay Ozbakkaloglu; Osman Gencel; Tuan D. Ngo. 2020. "Concretes containing waste-based materials under active confinement." Construction and Building Materials 270, no. : 121465.