Tailoring Confining Jacket for Concrete Column Using Ultra High Performance-Fiber Reinforced Cementitious Composites (UHP-FRCC) with High Volume Fly Ash (HVFA)

Abstract

Ultra-High Performance Fibre-Reinforced Cementitious Composites (UHP-FRCC) show excellent mechanical performances in terms of strength, ductility, and durability. Therefore, these cementitious materials have been successfully used for repairing, strengthening, and seismic retrofitting of old structures. However, UHP-FRCCs are not always environmental friendly products, especially in terms of the initial cost, due to the large quantity of cement that is contained in the mixture. Different rates of fly ash substitute herein part of the cement, and the new UHP-FRCCs are used to retrofit concrete columns to overcome this problem. To simulate the mechanical response of these columns, cylindrical specimens, which are made of normal concrete and reinforced with different UHP-FRCC jackets, are tested in uniaxial compression. Relationships between the size of the jacket, the percentage of cement replaced by fly ash, and the strength of the columns are measured and analyzed by means of the eco-mechanical approach. As a result, a replacement of approximately 50% of cement with fly ash, and a suitable thickness of the UHP-FRCC jacket, might ensure the lowest environmental impact without compromising the mechanical performances.

Strengthening of Concrete Column by Using the Wrapper Layer of Fibre Reinforced Concrete

“…The research [18] is focused on the mechanical properties and chloride resistance of chloride resistance of concrete reinforced with hybrid polypropylene and basalt fibres. Some researches are also focused on using fibre reinforced concrete for column strengthening [19], as in this paper, but without taking into account the influence of contact between old and new concrete and the columns are only in compression. The originality of the article is the use of FRC to strengthen vertical elements, such as columns, stressed by a combination of compression and bending (using the good properties of FRC not only in compression but also in tension), taking into account the contact resistance between the old and new parts of the cross-section.…”

Special Issue: Supplementary Cementitious Materials in Concrete, Part I

“…properties of modified cement matrix composites reinforced with fibers [14,[18][19][20]; • application of new types of supplementary cementitious materials [13,16,[21][22][23][24][25][26][27][28]; • characterization of various types of modified cement based materials [18,21,23,[25][26][27][28][29][30][31].…”

“…The issues of the original research papers and stat-of-the art reviews published in this Special Issue of Materials, and coming from over 45 international universities and scientific centres, can be divided as follows: permeability and diffusivity, which are directly related to the quality of concrete and to the durability in various aggressive environments [ 13 , 14 , 15 , 16 , 17 ]; properties of modified cement matrix composites reinforced with fibers [ 14 , 18 , 19 , 20 ]; application of new types of supplementary cementitious materials [ 13 , 16 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ]; characterization of various types of modified cement based materials [ 18 , 21 , 23 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ]. …”

“…Fantilli et al [ 19 ] investigated the use of ultra-high performance fibre-reinforced cementitious composites (UHP-FRCC), made with various replacement ratio of cement with fly ash, as a reinforcement material of existing concrete columns. Relationships between the size of the UHP-FRCC jacket, the percentage of cement replaced by fly ash, and the strength of the columns were measured and analyzed by means of the eco-mechanical approach.…”

Mechanical and Environmental Proprieties of UHP-FRCC Panels Bonded to Existing Concrete Beams

“…Among the possible solutions, reinforced concrete (RC) jackets and steel cages are the most used [1,2]. Additionally, jacketing using innovative materials, such as Fiber Reinforced Polymer (FRP) [3][4][5] and Ultra High-Performance Fiber-Reinforced Cementitious Composites (UHP-FRCC) [6][7][8], have been successfully introduced and applied in the last decades. In particular, UHP-FRCCs have also brought the interest of many researchers, who assert that for both new and existing structure a new construction era has started [9].…”