Mechanical properties and damage behavior of angle-ply CFRP laminates with discontinuous plies

This paper presents results from experiments on aged and seriously damaged reinforced concrete (RC) beams strengthened with different arrangements of external carbon fiber-reinforced polymer (CFRP) laminates and end anchorages. Seven RC beams from an old bridge, measuring 250 × 200 × 2300 mm, were tested. All specimens were loaded to yield load to evaluate initial mechanical properties. Then, these seriously damaged specimens were repaired using different CFRP-reinforcing schemes and reloaded to failure. The yield load growth due to CFRP reinforcement ranged from 5% to 36%. Different parameters including CFRP dimension and position, bonding length, and end anchorage were investigated and facilitated conclusions on beam ductility, load-midspan deflection response, and failure mode. This research contributes to knowledge about the CFRP repair of aged and seriously damaged beams to ensure better performance in overloaded conditions.

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Effect of Heat Treatment Process and Composition on Deformation and Damage Behavior of WHA under Detonation Loading

Journal of Physics Conference Series ◽

10.1088/1742-6596/2101/1/012067 ◽

2021 ◽

Vol 2101 (1) ◽

pp. 012067

Author(s):

J J Tang ◽

Z F Liang ◽

X Y Hu

Keyword(s):

Mechanical Properties ◽

Treatment Process ◽

High Strain ◽

Dynamic Mechanical Properties ◽

Damage Effect ◽

Tungsten Heavy Alloy ◽

Damage Behavior ◽

Explosion Test ◽

The Military ◽

Detonation Loading

Abstract The excellent material properties of tungsten heavy alloy (WHA) make it widely used in the military field. When used as killing elements of weapons, its dynamic mechanical properties under detonation loading directly determine the damage effect of weapons, which makes the research on its mechanical behaviors under high pressure and high strain rate loads such as detonation loading of great significance. In this paper, several WHAs with different compositions and processes are selected, and the mechanical properties and deformation and damage behavior under static explosion test are analyzed by combining macro and micro study, so as to provide guidance for the subsequent optimization of the performance design of WHA.

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Probabilistic-based characterisation of the mechanical properties of CFRP laminates

Construction and Building Materials ◽

10.1016/j.conbuildmat.2018.02.190 ◽

2018 ◽

Vol 169 ◽

pp. 132-141 ◽

Cited By ~ 6

Author(s):

S. Gomes ◽

D. Dias-da-Costa ◽

L.A.C. Neves ◽

S.A. Hadigheh ◽

P. Fernandes ◽

...

Keyword(s):

Mechanical Properties ◽

Cfrp Laminates

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Mechanical High-Temperature Properties and Damage Behavior of Coarse-Grained Alumina Refractory Metal Composites

Materials ◽

10.3390/ma12233927 ◽

2019 ◽

Vol 12 (23) ◽

pp. 3927

Author(s):

Anja Weidner ◽

Yvonne Ranglack-Klemm ◽

Tilo Zienert ◽

Christos G. Aneziris ◽

Horst Biermann

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Refractory Metals ◽

Coarse Grained ◽

Damage Behavior ◽

Niobium Oxides ◽

Alumina Refractory ◽

Increasing Temperature ◽

New Generation ◽

Refractory Composites

The present study provides the mechanical properties of a new generation of refractory composites based on coarse-grained Al2O3 ceramic and the refractory metals Nb and Ta. The materials were manufactured by refractory castable technology and subsequently sintered at 1600 °C for 4 h. The mechanical properties and the damage behavior of the coarse-grained refractory composites were investigated at high temperatures between 1300 and 1500 °C. The compressive strength is given as a function of temperature for materials with two different volume fractions of the refractory metals Ta and Nb. It is demonstrated that these refractory composites do not fail in a completely brittle manner in the studied temperature range. The compressive strength for all materials significantly decreases with increasing temperature. Failure occurred due to the formation of cracks along the ceramic/metal interfaces of the coarse-grained Al2O3 particles. In microstructural observations of sintered specimens, the formation of tantalates, as well as niobium oxides, were observed. The lower compressive strength of coarse-grained Nb-Al2O3 refractory composites compared to Ta-Al2O3 is probably attributed to the formation of niobium oxides. The formation of tantalates, however, seems to have no detrimental effect on compressive strength.

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Damage Behavior in Unidirectional CFRP Laminates with Fiber Discontinuity

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.79.294 ◽

2013 ◽

Vol 79 (799) ◽

pp. 294-303 ◽

Cited By ~ 1

Author(s):

Hayato NAKATANI ◽

Kenji NAKAYA ◽

Akira MATSUBA ◽

Yousuke KOUNO ◽

Shinji OGIHARA

Keyword(s):

Damage Behavior ◽

Cfrp Laminates

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Effects of Nano Organoclay and Wax on the Machining Temperature and Mechanical Properties of Carbon Fiber Reinforced Plastics (CFRP)

Journal of Composites Science ◽

10.3390/jcs3030085 ◽

2019 ◽

Vol 3 (3) ◽

pp. 85 ◽

Cited By ~ 1

Author(s):

El-Ghaoui ◽

Chatelain ◽

Ouellet-Plamondon ◽

Mathieu

Keyword(s):

Mechanical Properties ◽

Carbon Fiber ◽

Polycrystalline Diamond ◽

Fiber Reinforced ◽

Cfrp Laminates ◽

Carbon Fiber Reinforced Plastics ◽

Reinforced Plastics ◽

Fiber Reinforced Plastics ◽

Carbon Fiber Reinforced ◽

Pcd Tools

Carbon fiber reinforced plastics (CFRP) are appreciated for their high mechanical properties and lightness. Due to their heterogeneous nature, CFRP machining remains delicate. Damages are caused on the material and early tool wear occurs. The present study aims to evaluate the effects of fillers on CFRP machinability and mechanical behavior. CFRP laminates were fabricated by the vacuum assisted resin transfer molding (VARTM) process, using a modified epoxy resin. Three fillers (organoclay, hydrocarbon wax, and wetting agent) were mixed with the resin prior to the laminate infusion. Milling tests were performed with polycrystalline diamond (PCD) tools, equipped with thermocouples on their teeth. Machinability was then studied through the cutting temperatures and forces. Tensile, flexural, and short-beam tests were carried out on all samples to investigate the effects of fillers on mechanical properties. Fillers, especially wax, allowed us to observe an improvement in machinability. The best improvement was observed with 1% wax and 2% organoclay, which allowed a significant decrease in the cutting forces and the temperatures, and no deteriorations were seen on mechanical properties. These results demonstrate that upgrades to CFRP machining through the addition of nanoclays and wax is a path to explore.

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