scholarly journals Internal and External Reinforcement of Concrete Members by Use of Shape Memory Alloy and Fiber Reinforced Polymers under Cyclic Loading—A Review

Polymers ◽  
2018 ◽  
Vol 10 (4) ◽  
pp. 376 ◽  
Author(s):  
Azadeh Parvin ◽  
Janet Raad
Keyword(s):  
Cyclic Loading ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Reinforced Polymers ◽  
Concrete Members ◽  
External Reinforcement

scholarly journals The influence of carbon nanotubes and shape memory alloy wires to controlled impact resistance of polymer composites

2016 ◽  
Vol 51 (2) ◽  
pp. 273-285 ◽  
Author(s):  
Katerina Sofocleous ◽  
Vasileios M Drakonakis ◽  
Stephen L Ogin ◽  
Charalabos Doumanidis
Keyword(s):  
Carbon Nanotube ◽  
Carbon Fiber ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Polymer Composites ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Carbon Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Carbon Fiber Reinforced

Matrix as well as interlayer regions of laminated polymer composites have been reinforced with carbon nanotubes, additionally to shape memory alloy wires, in order to further enhance the overall material toughness and introduce the improved impact resistance mechanisms through micro- and nano-engineering. In this work, we examine carbon fiber reinforced polymer composites with constant carbon fiber volume fraction, further reinforced with carbon nanotube and shape memory alloy wires, under controlled impact. Single-type as well as multiple-type impact tests have been carried out, demonstrating that the energy absorption and damage development are similar in both impact tests for the same material. When the carbon nanotube and shape memory alloy wires reinforcements are compared separately, shape memory alloy-reinforced carbon fiber reinforced polymers present higher energy absorption than the carbon nanotube-reinforced carbon fiber reinforced polymers. When they are combined, although the carbon nanotube + shape memory alloy-reinforced carbon fiber reinforced polymers present similar energy absorption improvement to shape memory alloy-only carbon fiber reinforced polymers, the carbon nanotube addition increases toughness, resulting in damage initiation at higher depths of impact penetration.

Active Vortex Generator Deployed on Demand by Active Hybrid Composites From Shape Memory Alloys and Fiber Reinforced Polymers

2017 ◽  
Author(s):  
Martin Gurka ◽  
Sebastian Nissle ◽  
Moritz Hübler ◽  
Max Kaiser
Keyword(s):  
Shape Memory Alloys ◽  
Shape Memory ◽  
Flow Separation ◽  
Hybrid Composites ◽  
Vortex Generators ◽  
Fiber Reinforced Polymers ◽  
Fe Model ◽  
Fiber Reinforced ◽  
Reinforced Polymers ◽  
On Demand

High performance airfoils with laminar airflow exhibit minimum drag and maximum lift, but tend to sudden stall due to flow separation at low air speed. This requires an increased approach speed of the aircraft, resulting in less steep approaches and a higher noise exposure of the surroundings. New active vortex generators, deployed only on demand at low speed, energizing the boundary layer of air flow and reducing flow separation, can help to overcome this critical situation. Active hybrid composites, combining the actuation capability of shape memory alloys (SMA) with the possibility of tailoring the compliance of fiber reinforced polymers (FRP) on the materials level, provide an active aerodynamic system with high lightweight potential and small space requirements. Being one of the first applications of active hybrid structures from SMA and FRP we will demonstrate the potential of this new technology with an integrated system of active vortex generators for a glider. In this contribution we present - the design process, based on a FE-model and careful characterization of the actuating SMA and the composite material - manufacturing relevant aspects for reliable series production - the testing of single vortex generators in lab scale under aerodynamic load - and an overview of the whole system.

scholarly journals Reinforcement alternatives for beams under cyclic load

2020 ◽  
Vol 9 (2) ◽  
pp. 350
Author(s):  
Louay A. Aboul-Nour ◽  
Ragab S. Mahmoud ◽  
Mahmoud A. Khater ◽  
Nesma M. Moselhy
Keyword(s):  
Cyclic Loading ◽  
Load Capacity ◽  
Model Verification ◽  
Reinforced Concrete Beams ◽  
Flexural Behavior ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Material Technology ◽  
Element Analysis ◽  
Reinforced Polymers

The major cause of concrete structures deterioration is steel corrosion. Consequently, this situation has led researchers to study and test other reinforcement alternatives that are noncorrosive in nature. Rapidly emerging developments in the field of material technology has led to the development of fiber reinforced polymers (FRP). This research focuses on the flexural behavior of carbon, glass, aramid, and basalt (CFRP, GFRP, AFRP, and BFRP) fiber reinforced polymers bars as alternatives to the traditional steel reinforcement in concrete. The study involves a nonlinear numerical finite element analysis of a simply supported reinforced concrete beams subjected to cyclic loading, where the ANSYS program is utilized. The numerical model verification is executed on the experimental beams for ensuring the efficiency of ma-terial models, cyclic loading and various elements. Hysteresis curves are produced for each beam and analyzed, where loads, deflections, and cracks propagation are inspected and discussed. The results reveal that, the full replacement of traditional steel bars with CFRP bars gives the greatest increase in the ultimate load capacity by 38.5%. Also, other results are summarized in this paper. 

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