Fabric-Reinforced Cementitious Matrix (FRCM): A New Italian Guideline under Development

In addition toFibre-Reinfocedcomposite materials, which are made of long glass/carbon/aramid fibers embedded in a polymer matrix (FRP), the use ofFRCMcomposites (Fabric-Reinforced Cementitious Matrix) is becoming more and more widespread. As far as this specific case, the inorganic matrix guarantees many advantages, especially when dealing with masonry substrates, including a good compatibility from both a physical and a chemical point of view and the possibility of wet lay-up application. Despite their wide use in technical applications, the constitutive behavior and the failure mechanisms of FRCMs have not been adequately studied. As a consequence, a final assessment upon which criteria have to be used for verification and qualification ofFRCMsis still missing. In the context of a recent experimental program-still under development-cooperated by many Italian academic laboratories, that is aimed at detecting the main features of the constitutive behavior of these materials, a discussion seems to be appropriate on the initial experimental results obtained at Salerno University on manyFRCMspecimens tested under uniaxial tensile loads.

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Energy and seismic drawbacks of masonry: a unified retrofitting solution

Journal of Building Pathology and Rehabilitation ◽

10.1007/s41024-021-00121-6 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

F. Longo ◽

A. Cascardi ◽

P. Lassandro ◽

M. A. Aiello

Keyword(s):

Thermal Resistance ◽

Mechanical Performance ◽

Point Of View ◽

Experimental Program ◽

Masonry Walls ◽

Shear Tests ◽

Plane Shear ◽

Innovative Solutions ◽

Inorganic Matrix ◽

Comfort Criteria

AbstractAll over the world, a large part of existing buildings is not adequate to satisfy the safety requirement and the thermal comfort criteria. For this reason, the interest in structural and energy retrofitting systems has steadily grown in the last decades. In this scenario, an innovative thermal resistant geopolymer mortar has been developed and used for Inorganic Matrix Composite (IMC) systems aimed to a combined seismic and energy new retrofitting technique. The geopolymer-based IMC is able to ensure competitive mechanical properties with respect to the traditional lime-based IMCs and, at the same time, a significant reduction in thermal conductivity. In this paper, an experimental program is reported considering small-scaled masonry panels with double-side IMC-retrofitting and determining both the in-plane shear strength and the thermal resistance. The experimental shear tests are aimed to compare the mechanical performance of the geopolymer innovative systems with those of the traditional lime-based ones. Moreover, the thermal resistance gain of the innovative solutions was measured and compared with traditional systems. The results evidenced the effectiveness of the proposed technique that significantly improved the performances of masonry walls from both the thermal and the mechanical point of view.

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Tensile Properties of 3D-printed Continuous-Fiber-Reinforced Plastics

Materiale Plastice ◽

10.37358/mp.21.4.5552 ◽

2022 ◽

Vol 58 (4) ◽

pp. 271-282

Author(s):

Nicolae Florin Cofaru ◽

Adrian Pascu ◽

Mihaela Oleksik ◽

Radu Petruse

Keyword(s):

Composite Materials ◽

3D Printing ◽

Tensile Stress ◽

Experimental Tests ◽

Maximum Tensile Stress ◽

Point Of View ◽

Experimental Program ◽

Uniaxial Tensile ◽

Uniaxial Tensile Test ◽

Reinforced Plastics

Obtaining parts made of composite materials through 3D Printing Additive manufacturing have fully proved their usefulness due to a number of advantages such as: the possibility to directly create complex shapes without going through the classic process of transforming the semi-finished products into finished parts through technologies which consume resources and energy and are totally unfriendly to the environment. The main disadvantage of the parts made by 3D Printing technologies is that they are less resistant from a mechanical point of view. This was solved with the emergence of the 3D printers capable of printing composite parts consisting of a plastic matrix reinforced with continuous fibers. This research focuses on studying 4 types of composite materials from the point of view of their mechanical properties: Onyx - a rigid nylon in which micro carbon fibers are inserted and Onyx reinforced with carbon, fiber glass or kevlar. Standardized specimens were made for the uniaxial tensile test and the experimental program was designed evaluating: the Elastic modulus [GPa], the Maximum Tensile stress [MPa], the Tensile strain at maximum Tensile stress [mm/mm]. The principal strains were also determined, by means of the digital image technique made using the Aramis system from GOM. The experimental tests confirm that these new materials will be serious candidates to be used in the engineering applications in various fields.

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Testing Procedures for the Uniaxial Tensile Characterization of Fabric-Reinforced Cementitious Matrix Composites

Journal of Composites for Construction ◽

10.1061/(asce)cc.1943-5614.0000626 ◽

2016 ◽

Vol 20 (3) ◽

pp. 04015063 ◽

Cited By ~ 60

Author(s):

Diana Arboleda ◽

Francesca Giulia Carozzi ◽

Antonio Nanni ◽

Carlo Poggi

Keyword(s):

Uniaxial Tensile ◽

Matrix Composites ◽

Testing Procedures ◽

Cementitious Matrix ◽

Tensile Characterization ◽

Fabric Reinforced Cementitious Matrix

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Experimental Research on Bond Behaviour of Fabric Reinforced Cementitious Matrix Composites for Retrofitting Masonry Walls

International Journal of Concrete Structures and Materials ◽

10.1186/s40069-021-00460-1 ◽

2021 ◽

Vol 15 (1) ◽

Author(s):

Fayu Wang ◽

Nicholas Kyriakides ◽

Christis Chrysostomou ◽

Eleftherios Eleftheriou ◽

Renos Votsis ◽

...

Keyword(s):

Large Scale ◽

Tensile Tests ◽

Seismic Resistance ◽

Matrix Composites ◽

Bond Behaviour ◽

Cementitious Matrix ◽

The Matrix ◽

Rc Frame Buildings ◽

Direct Tensile ◽

Fabric Reinforced Cementitious Matrix

AbstractFabric reinforced cementitious matrix (FRCM) composites, also known as textile reinforced mortars (TRM), an inorganic matrix constituting fibre fabrics and cement-based mortar, are becoming a widely used composite material in Europe for upgrading the seismic resistance of existing reinforced concrete (RC) frame buildings. One way of providing seismic resistance upgrading is through the application of the proposed FRCM system on existing masonry infill walls to increase their stiffness and integrity. To examine the effectiveness of this application, the bond characteristics achieved between (a) the matrix and the masonry substrate and (b) the fabric and the matrix need to be determined. A series of experiments including 23 material performance tests, 15 direct tensile tests of dry fabric and composites, and 30 shear bond tests between the matrix and brick masonry, were carried out to investigate the fabric-to-matrix and matrix-to-substrate bond behaviour. In addition, different arrangements of extruded polystyrene (XPS) plates were applied to the FRCM to test the shear bond capacity of this insulation system when used on a large-scale wall.

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Experimental study on the behavior of carbon-fabric reinforced cementitious matrix composites in impressed current cathodic protection

Construction and Building Materials ◽

10.1016/j.conbuildmat.2020.120655 ◽

2020 ◽

Vol 264 ◽

pp. 120655

Author(s):

Ran Feng ◽

Jingzhou Zhang ◽

Ji-Hua Zhu ◽

Feng Xing

Keyword(s):

Experimental Study ◽

Cathodic Protection ◽

Matrix Composites ◽

Carbon Fabric ◽

Cementitious Matrix ◽

Impressed Current ◽

Fabric Reinforced Cementitious Matrix ◽

Impressed Current Cathodic Protection

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Performance of Plain Journal Bearings Operating Under Vortex Flow Conditions

Journal of Lubrication Technology ◽

10.1115/1.3451886 ◽

1974 ◽

Vol 96 (1) ◽

pp. 145-149 ◽

Cited By ~ 4

Author(s):

J. Freˆne ◽

M. Godet

Keyword(s):

Reynolds Number ◽

Friction Torque ◽

Point Of View ◽

Taylor Vortex ◽

Experimental Program ◽

Frictional Torque ◽

Taylor Vortices ◽

Attitude Angle ◽

Relative Eccentricity ◽

High Reynolds

An experimental program conducted on an original device was undertaken to study the performance of plain bearings operating at sufficiently high Reynolds number to introduce Taylor vortices. Curves of relative eccentricity, attitude angle, and friction torque were obtained versus speed and load. Experimental results conducted for Reynolds number smaller than 1100 indicate that both laminar and Taylor vortex regimes are encountered. The occurrence of the vortices is identified by a break in the slope of the friction torque versus speed curves. The position of the break is in good agreement with the theoretical predictions of Di Prima and Ritchie. From the practical point of view, the data show that for constant viscosity the occurence of Taylor vortices does not alter the curves of eccentricity versus either speed or load but modifies the attitude angle and frictional torque. In turn, the increase in frictional torque, and subsequently of temperature may cause a decrease in viscosity and thus a drop in load carrying capacity for fluids such as oils whose variations of viscosity with temperature is large.

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Verification of the Structural Performance of Textile Reinforced Reactive Powder Concrete Sandwich Facade Elements

Applied Sciences ◽

10.3390/app9122456 ◽

2019 ◽

Vol 9 (12) ◽

pp. 2456 ◽

Cited By ~ 3

Author(s):

Mathias Flansbjer ◽

Natalie Williams Portal ◽

Daniel Vennetti

Keyword(s):

Structural Model ◽

Structural Performance ◽

Wind Loading ◽

Experimental Program ◽

Reactive Powder Concrete ◽

Uniaxial Tensile ◽

Material Development ◽

Pull Out ◽

Glass Fiber Reinforced ◽

Reactive Powder

As a part of the SESBE (Smart Elements for Sustainable Building Envelopes) project, non-load bearing sandwich elements were developed with Textile Reinforced Reactive Powder Concrete (TRRPC) for outer and inner facings, Foam Concrete (FC) for the insulating core and Glass Fiber Reinforced Polymer (GFRP) continuous connectors. The structural performance of the developed elements was verified at various levels by means of a thorough experimental program coupled with numerical analysis. Experiments were conducted on individual materials (i.e., tensile and compressive tests), composites (i.e., uniaxial tensile, flexural and pull-out tests), as well as components (i.e., local anchorage failure, shear, flexural and wind loading tests). The experimentally yielded material properties were used as input for the developed models to verify the findings of various component tests and to allow for further material development. In this paper, the component tests related to local anchorage failure and wind loading are presented and coupled to a structural model of the sandwich element. The validated structural model provided a greater understanding of the physical mechanisms governing the element’s structural behavior and its structural performance under various dead and wind load cases. Lastly, the performance of the sandwich elements, in terms of composite action, was shown to be greatly correlated to the properties of the GFRP connectors, such as stiffness and strength.

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