scholarly journals Materials for Production of High and Ultra-High Performance Concrete: Review and Perspective of Possible Novel Materials

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4304
Author(s):  
Markssuel Teixeira Marvila ◽  
Afonso Rangel Garcez de de Azevedo ◽  
Paulo R. de de Matos ◽  
Sergio Neves Monteiro ◽  
Carlos Maurício Fontes Vieira
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Review Article ◽  
Cement Matrix ◽  
Bibliographic Databases ◽  
Future Research ◽  
Chemical Additives ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Essential Components

This review article proposes the identification and basic concepts of materials that might be used for the production of high-performance concrete (HPC) and ultra-high-performance concrete (UHPC). Although other reviews have addressed this topic, the present work differs by presenting relevant aspects on possible materials applied in the production of HPC and UHPC. The main innovation of this review article is to identify the perspectives for new materials that can be considered in the production of novel special concretes. After consulting different bibliographic databases, some information related to ordinary Portland cement (OPC), mineral additions, aggregates, and chemical additives used for the production of HPC and UHPC were highlighted. Relevant information on the application of synthetic and natural fibers is also highlighted in association with a cement matrix of HPC and UHPC, forming composites with properties superior to conventional concrete used in civil construction. The article also presents some relevant characteristics for the application of HPC and UHPC produced with alkali-activated cement, an alternative binder to OPC produced through the reaction between two essential components: precursors and activators. Some information about the main types of precursors, subdivided into materials rich in aluminosilicates and rich in calcium, were also highlighted. Finally, suggestions for future work related to the application of HPC and UHPC are highlighted, guiding future research on this topic.

scholarly journals Ultra-high-performance concrete with local high unburned carbon fly ash

DYNA ◽  
2021 ◽  
Vol 88 (216) ◽  
pp. 38-47
Author(s):  
Joaquín Abellán García ◽  
Nancy Torres Castellanos ◽  
Jaime Antonio Fernandez Gomez ◽  
Andres Mauricio Nuñez Lopez
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
High Performance ◽  
High Performance Concrete ◽  
Unburned Carbon ◽  
High Tech ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
The Cost

Ultra-high-performance concrete (UHPC) is a kind of high-tech cementitious material with superb mechanical and durability properties compared to other types of concrete. However, due to the high content of cement and silica fume used, the cost and environmental impact of UHPC is considerably higher than conventional concrete. For this reason, several efforts around the world have been made to develop UHPC with greener and less expensive local pozzolans. This study aimed to design and produce UHPC using local fly ash available in Colombia. A numerical optimization, based on Design of Experiments (DoE) and multi-objective criteria, was performed to obtain a mixture with the proper flow and highest compressive strength, while simultaneously having the minimum content of cement. The results showed that, despite the low quality of local fly ashes in Colombia, compressive strength values of 150 MPa without any heat treatment can be achieved.

scholarly journals Ground Glass Pozzolan in Conventional, High, and Ultra-High Performance Concrete

2018 ◽  
Vol 149 ◽  
pp. 01005 ◽  
Author(s):  
Arezki Tagnit-Hamou ◽  
Ablam Zidol ◽  
Nancy Soliman ◽  
Joris Deschamps ◽  
Ahmed Omran
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
High Strength ◽  
Ground Glass ◽  
Strengthening Effect ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Supplementary Cementitious Material ◽  
Pozzolanic Material ◽  
And Performance

Ground-glass pozzolan (G) obtained by grinding the mixed-waste glass to same fineness of cement can act as a supplementary-cementitious material (SCM), given that it is an amorphous and a pozzolanic material. The G showed promising performances in different concrete types such as conventional concrete (CC), high-performance concrete (HPC), and ultra-high performance concrete (UHPC). The current paper reports on the characteristics and performance of G in these concrete types. The use of G provides several advantages (technological, economical, and environmental). It reduces the production cost of concrete and decrease the carbon footprint of a traditional concrete structures. The rheology of fresh concrete can be improved due to the replacement of cement by non-absorptive glass particles. Strength and rigidity improvements in the concrete containing G are due to the fact that glass particles act as inclusions having a very high strength and elastic modulus that have a strengthening effect on the overall hardened matrix.

scholarly journals Effect of Elevated Temperature on the Bond Strength of Prestressing Reinforcement in UHPC

Materials ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 4990
Author(s):  
Petr Pokorný ◽  
Jiří Kolísko ◽  
David Čítek ◽  
Michaela Kostelecká
Keyword(s):  
Bond Strength ◽  
High Performance ◽  
Elevated Temperatures ◽  
High Performance Concrete ◽  
Future Research ◽  
Ultra High Performance Concrete ◽  
Negative Effect ◽  
Laboratory Investigations ◽  
Increasing Temperature ◽  
Positive Effect

The study explores the effect of elevated temperatures on the bond strength between prestressing reinforcement and ultra-high performance concrete (UHPC). Laboratory investigations reveal that the changes in bond strength correspond well with the changes in compressive strength of UHPC and their correlation can be mathematically described. Exposition of specimens to temperatures up to 200 °C does not reduce bond strength as a negative effect of increasing temperature is outweighed by the positive effect of thermal increase on the reactivity of silica fume in UHPC mixture. Above 200 °C, bond strength significantly reduces; for instance, a decrease by about 70% is observed at 800 °C. The decreases in compressive and bond strengths for temperatures above 400 °C are related to the changes of phase composition of UHPC matrix (as revealed by X-ray powder diffraction) and the changes in microstructure including the increase of porosity (verified by mercury intrusion porosimetry and observation of confocal microscopy) and development cracks detected by scanning electron microscopy. Future research should investigate the effect of relaxation of prestressing reinforcement with increasing temperature on bond strength reduction by numerical modelling.

scholarly journals State of the Art: Mechanical Properties of Ultra-High Performance Concrete

2017 ◽  
Vol 3 (3) ◽  
pp. 190-198 ◽  
Author(s):  
Mohamadtaqi Baqersad ◽  
Ehsan Amir Sayyafi ◽  
Hamid Mortazavi Bak
Keyword(s):  
Mechanical Properties ◽  
High Performance ◽  
High Performance Concrete ◽  
State Of The Art ◽  
High Strength ◽  
Structural Members ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
The Past ◽  
Very High

During the past decades, there has been an extensive attention in using Ultra-High Performance Concrete (UHPC) in the buildings and infrastructures construction. Due to that, defining comprehensive mechanical properties of UHPC required to design structural members is worthwhile. The main difference of UHPC with the conventional concrete is the very high strength of UHPC, resulting designing elements with less weight and smaller sizes.  However, there have been no globally accepted UHPC properties to be implemented in the designing process. Therefore, in the current study, the UHPC mechanical properties such as compressive and tensile strength, modulus of elasticity and development length for designing purposes are provided based on the reviewed literature. According to that, the best-recommended properties of UHPC that can be used in designing of UHPC members are summarized. Finally, different topics for future works and researches on UHPC’s mechanical properties are suggested.

scholarly journals EFEITO DA ADIÇÃO DE FIBRAS DE AÇO E POLIMÉRICAS NA RESISTÊNCIA À COMPRESSÃO DO CONCRETO DE ULTRA ALTO DESEMPENHO

2020 ◽  
Vol 16 (1) ◽  
pp. 26-35
Author(s):  
Carlos Eduardo Tino Balestra ◽  
Jennifer Stephane Ozelame ◽  
Gustavo Savaris
Keyword(s):  
High Performance ◽  
New Technologies ◽  
High Performance Concrete ◽  
Steel Fibers ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Residual Resistance ◽  
Different Types ◽  
Polyethylene Fibers ◽  
Rupture Behavior

RESUMO: A exigência de materiais com desempenho superior aos utilizados usualmente na construção civil impulsiona pesquisas que visam o desenvolvimento de novas tecnologias. Neste contexto, surgem os concretos de ultra alto desempenho reforçados com fibras (UHPFRC), que se destacam pelas elevadas resistências à compressão e à tração e maior ductilidade em relação a um concreto convencional. O presente trabalho teve como objetivo principal avaliar experimentalmente a resistência à compressão e comportamento pós ruptura de UHPFRC com diferentes tipos e dosagens de fibras, utilizando materiais disponíveis no mercado brasileiro, visando o emprego deste material nos processos construtivos atuais. A partir de um traço de concreto de ultra alto desempenho foram definidas misturas de UHPFRC com fibras de aço e de fibras de polietileno utilizando volumes de 0,5% e 1% de fibras. Os resultados obtidos foram comparados a um concreto de referência sem fibras, demonstrando que as fibras melhoram a ductilidade do concreto e provém uma resistência residual ao mesmo, sendo observados, após sua fratura, picos de recuperação graças à melhor aderência das fibras ao concreto. Além disso, para ambas as fibras, uma maior quantidade de fibras auxiliou a combater as rupturas bruscas observadas após concretos sem fibras esgotarem sua capacidade resistente. ABSTRACT: The demand for materials with higher performance than those usually used in civil construction stimulate researches aimed at the development of new technologies. In this context, ultra high performance fibers reinforced concrete (UHPFRC) stands out due to the high compressive and tensile strengths and higher ductility compared to conventional concrete. The present work had as main objective to evaluate experimentally the compressive strength and post - rupture behavior of UHPFRC with different types and dosages of fibers, using materials available in Brazil, aiming the use of these material in the current constructive processes. UHPFRC mixtures with steel fibers and polyethylene fibers using 0.5% and 1% fiber volumes were defined from an ultra high performance concrete mixture. The results obtained were compared to a reference concrete without fibers, demonstrating that the fibers improve the ductility of the concrete and provide a residual resistance after the exemplar fracture, recovery peaks due to the better adhesion of the fibers to the concrete. In addition, for both fibers, a greater amount of fibers helped to avoid sudden ruptures observed after concrete without fibers reached their resistant capacity.

scholarly journals Influence of high volumes of silica fume on the rheological behavior of oil well cement pastes

2021 ◽  
Author(s):  
Jedadiah Burroughs ◽  
Jason Weiss ◽  
John Haddock
Keyword(s):  
Silica Fume ◽  
Rheological Behavior ◽  
High Performance ◽  
High Performance Concrete ◽  
Oil Well ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Cement Pastes ◽  
Specific Source ◽  
Well Cement

Specialized classes of concrete, such as ultra-high-performance concrete, use volumes of silica fume in concrete that are higher than those in conventional concrete, resulting in increased water demand and mixing difficulty. This study considered the effects of eight different silica fumes in three dosages (10%, 20%, 30%) with three w/b (0.20, 0.30, 0.45) on rheological behavior as characterized by the Herschel-Bulkley model. Results indicated that the specific source of silica fume used, in addition to dosage and w/b, had a significant effect on the rheological behavior. As such, all silica fumes cannot be treated as equivalent or be directly substituted one for another without modification of the mixture proportion. The rheology of cement pastes is significantly affected by the physical properties of silica fume more so than any chemical effects.

Innovative Approach to Repair Corroded Steel Piles using Ultra-High Performance Concrete

2020 ◽  
Vol 2674 (12) ◽  
pp. 1-14
Author(s):  
Binod Shrestha ◽  
Ahmed Gheni ◽  
Mohanad M. Abdulazeez ◽  
Mohamed A. ElGawady
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Load Capacity ◽  
Ultra High Performance Concrete ◽  
Conventional Concrete ◽  
Alkaline Salt ◽  
Axial Load Capacity ◽  
Steel Piles ◽  
Existing Bridges ◽  
Precast Elements

Steel H-piles are a common structural system in existing bridges. Many steel H-piles have been corroded as a result of severe weather and acid/alkaline salt exposures, causing a reduction in the axial load capacity. This paper experimentally investigates the use of ultra-high performance concrete (UHPC) encasement as a novel repair method for corroded steel H-pile. UHPC displays better tensile strength, early compressive strength, workability, and durability compared with conventional concrete. The proposed repair is used to bridge the corroded section in H-pile using either a cast-in-place or precast UHPC elements. A series of push-out tests was conducted on eight full-scale piles to assess the axial force that can be transferred through shear studs and bond between the UHPC and steel piles. The test parameters include the type of casting of the UHPC, that is, cast-in-place versus precast elements, thickness and shape of the UHPC elements, an inclusion of carbon fiber reinforced polymer (CFRP) grid, number and grade of bolts, an inclusion of washer, and applying torque on the bolts. The experimental work demonstrated that the UHPC precast repair can be easily implemented. Moreover, using 57 mm (2.25 in.) thick UHPC plates reinforced by two layers of the CFRP grid was capable of transferring up to 81% of the squash load of the H-pile.

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