Research on the residual tensile strength of composite reinforcing bars exposed to elevated temperatures

Abstract Paper describes a testing procedure for the determination of tensile strength of the composite reinforcing bars subjected to elevated temperatures. Experimentally obtained results on GFRP bars with different diameter are presented and discussed. Moreover, a brief comparison with an analytical approach was included. Almost identical temperature reduction rate of tensile strength was observed for all tested specimens, regardless diameter of the bar. Therefore, it can be expected, that different bar diameter should not significantly affect the results especially if steady state conditions were assumed.

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Experimental investigation on SFRC behaviour under elevated temperature

Journal of Structural Fire Engineering ◽

10.1108/jsfe-05-2017-0034 ◽

2017 ◽

Vol 8 (3) ◽

pp. 287-299 ◽

Cited By ~ 3

Author(s):

Vadims Goremikins ◽

Lukas Blesak ◽

Josef Novak ◽

Frantisek Wald

Keyword(s):

Tensile Strength ◽

Compressive Strength ◽

Elevated Temperatures ◽

Bending Strength ◽

Testing Procedure ◽

Split Tensile Strength ◽

Content Type ◽

Steel Fibre Reinforced Concrete ◽

Ultimate Bending Strength

Purpose This work aims to present an experimental study of steel fibre-reinforced concrete (SFRC) subjected to high temperature, especially focusing on residual behaviour. Design/methodology/approach Compressive strength and split tensile strength of SFRC cubes and ultimate bending strength of prisms were evaluated under ambient and elevated temperatures. The specimens were heated by ceramic heaters and then repacked for testing. Findings The results showed that a compressive strength of SFRC is reduced by 38 and 66 per cent, tensile strength is reduced by 25 and 59 per cent and ultimate bending force is reduced by 33 and 56 per cent in case of 400°C and 600°C, respectively, comparing with ambient temperature. Originality value The developed testing procedure could be used for determination of material properties of SFRC under elevated temperatures.

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An Energy-Based Axial Isothermal-Mechanical Fatigue Lifing Method

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4007121 ◽

2012 ◽

Vol 134 (10) ◽

Cited By ~ 8

Author(s):

John Wertz ◽

Todd Letcher ◽

M.-H. Herman Shen ◽

Onome Scott-Emuakpor ◽

Tommy George ◽

...

Keyword(s):

Strain Energy ◽

Thermal Loading ◽

Elevated Temperatures ◽

Testing Procedure ◽

Mechanical Fatigue ◽

Full Life ◽

Energy Dissipated ◽

Life Predictions ◽

Quasi Static Process

An energy-based fatigue lifing method for the determination of the full-life and critical-life of in-service structures subjected to axial isothermal-mechanical fatigue (IMF) has been developed. The foundation of this procedure is the energy-based axial room-temperature lifing model, which states: the total strain energy dissipated during both a quasi-static process and a dynamic (fatigue) process is the same material property. The axial IMF lifing framework is composed of the following entities: (1) the development of an axial IMF testing capability; (2) the creation of a testing procedure capable of assessing the strain energy dissipated during both a quasi-static process and a dynamic process at elevated temperatures; and (3) the incorporation of the effect of thermal loading into the axial fatigue lifing model. Both an axial IMF capability and a detailed testing procedure were created. The axial IMF capability was employed to produce full-life and critical-life predictions as functions of temperature, which were shown to have an excellent correlation with experimental fatigue data. For the highest operating temperature, the axial IMF full-life prediction was compared to lifing predictions made by both the universal slopes and the uniform material law prediction and was found to be more accurate at an elevated temperature.

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Determination of tensile strength of GFRP bars using flexure tests

Construction and Building Materials ◽

10.1016/j.conbuildmat.2021.125630 ◽

2022 ◽

Vol 314 ◽

pp. 125630

Author(s):

Philip Prakash Lochan ◽

Maria Anna Polak

Keyword(s):

Tensile Strength ◽

Gfrp Bars

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An Energy-Based Axial Isothermal-Mechanical Lifing Procedure

Volume 6: Structures and Dynamics, Parts A and B ◽

10.1115/gt2011-45261 ◽

2011 ◽

Author(s):

John Wertz ◽

M.-H. Herman Shen ◽

Onome Scott-Emuakpor ◽

Tommy George ◽

Charles Cross

Keyword(s):

Strain Energy ◽

Elevated Temperatures ◽

Testing Procedure ◽

Effect Of Temperature ◽

Activation Temperature ◽

Fatigue Process ◽

Fracture Event ◽

Operating Temperatures ◽

Total Strain Energy Density

An energy-based fatigue lifing procedure for the determination of fatigue life and critical life of in-service structures subjected to axial isothermal-mechanical fatigue (IMF) has been developed. The foundation of this procedure is the energy-based axial room-temperature fatigue model, which states: the total strain energy density accumulated during both a monotonic fracture event and a fatigue process is the same material property. The energy-based axial IMF lifing framework is composed of the following entities: (1) the development of an axial IMF testing capability; (2) the creation of a testing procedure capable of assessing the strain energy accrued during both a monotonic fracture process and a fatigue process at various elevated temperatures; and (3), the incorporation of the effect of temperature into the axial fatigue lifing model. Both an axial IMF capability and a detailed testing procedure were created. The axial IMF capability was employed in conjunction with the monotonic fracture curve testing procedure to produce eight fracture curves at three operating temperatures. The strain energy densities for these fracture curves were compared, leading to the assumption of constant monotonic fracture energy at operating temperatures below the creep activation temperature.

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An Energy-Based Axial Isothermal-Mechanical Fatigue Lifing Method

Volume 7: Structures and Dynamics, Parts A and B ◽

10.1115/gt2012-68889 ◽

2012 ◽

Cited By ~ 1

Author(s):

John Wertz ◽

Todd Letcher ◽

M.-H. Herman Shen ◽

Onome Scott-Emuakpor ◽

Tommy George ◽

...

Keyword(s):

Strain Energy ◽

Thermal Loading ◽

Elevated Temperatures ◽

Testing Procedure ◽

Mechanical Fatigue ◽

Full Life ◽

Energy Dissipated ◽

Life Predictions ◽

Quasi Static Process

An energy-based fatigue lifing method for the determination of the full-life and critical-life of in-service structures subjected to axial isothermal-mechanical fatigue (IMF) has been developed. The foundation of this procedure is the energy-based axial room-temperature lifing model, which states: the total strain energy dissipated during both a quasi-static process and a dynamic (fatigue) process is the same material property. The axial IMF lifing framework is composed of the following entities: (1) the development of an axial IMF testing capability; (2) the creation of a testing procedure capable of assessing the strain energy dissipated during both a quasi-static process and a dynamic process at elevated temperatures; and (3), the incorporation of the effect of thermal loading into the axial fatigue lifing model. Both an axial IMF capability and a detailed testing procedure were created. The axial IMF capability was employed to produce full-life and critical-life predictions as functions of temperature, which were shown to have excellent correlation with experimental fatigue data. For the highest operating temperature, the axial IMF full-life prediction was compared to lifing predictions made by both the Universal Slopes and the Uniform Material Law prediction and was found to be more accurate at elevated temperature.

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