Preliminary Fatigue Tests on Concrete Exposure to Temperature of up to 300°C

This paper presents the results of elevated temperatures on the compressive of high fly ash content concrete (HFCC). The specimens were prepared with three different replacements of cement by fly ash 30%, 40% and 50% by mass and the residual compressive strength was tested after exposure to elevated temperature 250, 450, 550 and 650°C and room temperature respectively. The results showed that the compressive strength apparently decreased with the elevated temperature increased. The presence of fly ash was effective for improvement of the relative strength, which was the ratio of residual compressive strength after exposure to elevated temperature and ordinary concrete. The relative compressive strength of fly ash concrete was higher than those of ordinary concrete. Based on the experiments results, the alternating simulation formula to determine the relationship among relative strength, elevated temperature and fly ash replacement is developed by using regression of results, which provides the theoretical basis for the evaluation and repair of HFCC after elevated temperature.

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Isothermal Fatigue Behavior and Damage Modeling of a High Temperature Woven PMC

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.483176 ◽

1999 ◽

Vol 122 (1) ◽

pp. 62-68 ◽

Cited By ~ 1

Author(s):

A. L. Gyekenyesi

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Elevated Temperatures ◽

Fatigue Behavior ◽

Stiffness Degradation ◽

Fatigue Properties ◽

Residual Compressive Strength ◽

Stiffness Reduction ◽

Fatigue Damage Accumulation ◽

Strength Tests

This study focuses on the fully reversed fatigue behavior exhibited by a carbon fiber/polyimide resin woven laminate at room and elevated temperatures. Nondestructive video edge view microscopy and destructive sectioning techniques were used to study the microscopic damage mechanisms that evolved. The elastic stiffness was monitored and recorded throughout the fatigue life of the coupon. In addition, residual compressive strength tests were conducted on fatigue coupons with various degrees of damage as quantified by stiffness reduction. Experimental results indicated that the monotonic tensile properties were only minimally influenced by temperature, while the monotonic compressive and fully reversed fatigue properties displayed greater reductions due to the elevated temperature. The stiffness degradation, as a function of cycles, consisted of three stages; a short-lived high degradation period, a constant degradation rate segment covering the majority of the life, and a final stage demonstrating an increasing rate of degradation up to failure. Concerning the residual compressive strength tests at room and elevated temperatures, the elevated temperature coupons appeared much more sensitive to damage. At elevated temperatures, coupons experienced a much larger loss in compressive strength when compared to room temperature coupons with equivalent damage. The fatigue damage accumulation law proposed for the model incorporates a scalar representation for damage, but admits a multiaxial, anisotropic evolutionary law. The model predicts the current damage (as quantified by residual stiffness) and remnant life of a composite that has undergone a known load at temperature. The damage/life model is dependent on the applied multiaxial stress state as well as temperature. Comparisons between the model and data showed good predictive capabilities concerning stiffness degradation and cycles to failure. [S0742-4795(00)01001-2]

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Application of a √ area -Approach for Fatigue Assessment of Cast Aluminum Alloys at Elevated Temperature

Metals ◽

10.3390/met8121033 ◽

2018 ◽

Vol 8 (12) ◽

pp. 1033 ◽

Cited By ~ 10

Author(s):

Roman Aigner ◽

Christian Garb ◽

Martin Leitner ◽

Michael Stoschka ◽

Florian Grün

Keyword(s):

Elevated Temperature ◽

Fatigue Strength ◽

Room Temperature ◽

Elevated Temperatures ◽

Damage Mechanism ◽

Cyclic Fatigue ◽

Fatigue Tests ◽

Cast Aluminum ◽

Fatigue Assessment ◽

Cast Aluminum Alloys

This paper contributes to the effect of elevated temperature on the fatigue strength of common aluminum cast alloys EN AC-46200 and EN AC-45500. The examination covers both static as well as cyclic fatigue investigations to study the damage mechanism of the as-cast and post-heat-treated alloys. The investigated fracture surfaces suggest a change in crack origin at elevated temperature of 150 ∘ C. At room temperature, most fatigue tests reveal shrinkage-based micro pores as their crack initiation, whereas large slipping areas occur at elevated temperature. Finally, a modified a r e a -based fatigue strength model for elevated temperatures is proposed. The original a r e a model was developed by Murakami and uses the square root of the projected area of fatigue fracture-initiating defects to correlate with the fatigue strength at room temperature. The adopted concept reveals a proper fit for the fatigue assessment of cast Al-Si materials at elevated temperatures; in detail, the slope of the original model according to Murakami should be decreased at higher temperatures as the spatial extent of casting imperfections becomes less dominant at elevated temperatures. This goes along with the increased long crack threshold at higher operating temperature conditions.

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Fatigue Behavior of a 22Cr-20Ni-18Co-Fe Alloy at Elevated Temperatures

Journal of Engineering Materials and Technology ◽

10.1115/1.2904255 ◽

1994 ◽

Vol 116 (1) ◽

pp. 54-61 ◽

Cited By ~ 6

Author(s):

T. H. Krukemyer ◽

A. Fatemi ◽

R. W. Swindeman

Keyword(s):

Experimental Investigation ◽

Room Temperature ◽

Elevated Temperatures ◽

Fatigue Behavior ◽

Fatigue Tests ◽

Frequency Separation ◽

Isothermal Fatigue ◽

Deformation Properties ◽

Fatigue Data ◽

Haynes Alloy

An experimental investigation was conducted on Haynes Alloy 556 to study the fatigue behavior of the material at elevated temperatures. Fatigue tests were run at constant temperatures ranging from room temperature to 871°C with strain ranges from 0.265 to 1.5 percent resulting in lives between 102 and 106 cycles. Cyclic deformation properties were evaluated based on the fatigue data. Three fatigue life models were evaluated for their ability to predict the isothermal fatigue lives of the material. These included the Ostergren, Frequency Separation and Stress-Strain-Time models. Strengths and weaknesses of each model are discussed based on the experimental results.

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COMPRESSIVE STRENGTH OF CONCRETE WITH FIBRES AT ELEVATED TEMPERATURE

Jurnal Teknologi ◽

10.11113/jt.v78.8553 ◽

2016 ◽

Vol 78 (5-4) ◽

Cited By ~ 1

Author(s):

Clotilda Petrus ◽

Huurun ‘Ain Azhar ◽

Goh Lyn Dee ◽

Ruqayyah Ismail ◽

Anizahyati Alisibramulisi

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Steel Fibre ◽

Single Fibre ◽

Single Type ◽

Test Results ◽

Severe Damage ◽

Compressive Strength Test ◽

Hybrid Specimen ◽

Compressive Strength Of Concrete

Concrete, when exposed to high temperature, can cause spalling, cracking, and severe damage, which could lead to a sudden collapse of a building. One of the solutions for overcoming this weakness of concrete is by incorporating fibres in the concrete mix. Concrete incorporated with more than one type of fibres is often known as hybrid concrete. In this paper, the compressive strength of the hybrid concrete when exposed to elevated temperature is studied. The result is compared to concrete mixed with a single type of fibre of polypropylene or steel fibres. An observation of spalling is also carried out to verify the compressive strength test. The test results showed that both the single fibre specimens with steel fibre and hybrid specimen improved by 23.34% and 24.60% in residual strength compared with other residual strengths of concrete specimens.

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Elevated Temperature Fatigue Behavior of 2 1/4 Cr-1 Mo Steel

Journal of Pressure Vessel Technology ◽

10.1115/1.3454304 ◽

1975 ◽

Vol 97 (4) ◽

pp. 252-257 ◽

Cited By ~ 6

Author(s):

C. R. Brinkman ◽

M. K. Booker ◽

J. P. Strizak ◽

W. R. Corwin

Keyword(s):

Elevated Temperature ◽

Room Temperature ◽

Fatigue Behavior ◽

Cyclic Hardening ◽

Fatigue Tests ◽

Annealed Condition ◽

Temperature Range ◽

Hardening And Softening

Results are reported for a number of load and strain controlled fatigue tests conducted over the temperature range of room temperature to 1000°F (538°C). Cyclic hardening and softening characteristics for a single heat of 2 1/4 Cr-1 Mo steel in the isothermally annealed condition are discussed. Comparisons of the data generated in this effort are made with data available from the literature and from these compilations possible ASME design fatigue curves were prepared covering continuous high and low cycle behavior over the temperature range of room temperature to 1100°F (593°C). Equations for these design curves are also given.

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Low-Cycle Fatigue Behavior of Small Slice Specimens of Zircaloy-4 at Elevated Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.324-325.1241 ◽

2006 ◽

Vol 324-325 ◽

pp. 1241-1244 ◽

Cited By ~ 1

Author(s):

Li Xun Cai ◽

Yu Ming Ye

Keyword(s):

Elevated Temperature ◽

Low Cycle Fatigue ◽

Fatigue Behavior ◽

Cyclic Hardening ◽

Cyclic Softening ◽

Fatigue Tests ◽

Uniaxial Strain ◽

Transverse Strain ◽

Test Results ◽

Element Analysis

A series of strain fatigue tests were carried out on small bugle-like slice-specimens of Zr-4 alloy at 20 and 400. According to Elastic and Plastic Finite Element Analysis and assumption of local damage equivalence, a strain formula was given to transform transverse strain of the specimen to uniaxial strain. Based on the test results of the alloy and the strain transform formula, M-C (Manson-Coffin) models to be used for estimating uniaxial fatigue life of Zr-4 alloy were obtained. The results show that, the alloy mainly behaves as cyclic softening at 20 and as cyclic hardening at 400, and the elevated temperature can lead serious additional fatigue damage of the alloy and the effect of the elevated temperature impairs gradually with increasing of amplitude strain. A conclusion is helpful that prediction life by using M-C model based on traditional strain transform equation is quite conservative when uniaxial strain amplitude is less than 0.5%.

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Isothermal Fatigue Behavior and Damage Modeling of a High Temperature Woven PMC

Volume 5: Manufacturing Materials and Metallurgy; Ceramics; Structures and Dynamics; Controls, Diagnostics and Instrumentation; Education ◽

10.1115/98-gt-106 ◽

1998 ◽

Author(s):

Andrew L. Gyekenyesi

Keyword(s):

Compressive Strength ◽

Elevated Temperature ◽

Elevated Temperatures ◽

Fatigue Behavior ◽

Stiffness Degradation ◽

Fatigue Properties ◽

Residual Compressive Strength ◽

Stiffness Reduction ◽

Fatigue Damage Accumulation ◽

Strength Tests

This study focuses on the fully reversed fatigue behavior exhibited by a carbon fiber/polyimide resin woven laminate at room and elevated temperatures. Nondestructive video edge view microscopy and destructive sectioning techniques were used to study the microscopic damage mechanisms that evolved. The elastic stiffness was monitored and recorded throughout the fatigue life of the coupon. In addition, residual compressive strength tests were conducted on fatigue coupons with various degrees of damage as quantified by stiffness reduction. Experimental results indicated that the monotonic tensile properties were only minimally influenced by temperature, while the monotonic compressive and fully reversed fatigue properties displayed greater reductions due to the elevated temperature. The stiffness degradation, as a function of cycles, consisted of three stages; a short-lived high degradation period, a constant degradation rate segment covering the majority of the life, and a final stage demonstrating an increasing rate of degradation up to failure. Concerning the residual compressive strength tests at room and elevated temperatures, the elevated temperature coupons appeared much more sensitive to damage. At elevated temperatures, coupons experienced a much larger loss in compressive strength when compared to room temperature coupons with equivalent damage. The fatigue damage accumulation law proposed for the model incorporates a scalar representation for damage, but admits a multiaxial, anisotropic evolutionary law. The model predicts the current damage (as quantified by residual stiffness) and remnant life of a composite that has undergone a known load at temperature. The damage/life model is dependent on the applied multiaxial stress state as well as temperature. Comparisons between the model and data showed good predictive capabilities concerning stiffness degradation and cycles to failure.

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Behavior of High Strength Concrete Subjected to Elevated Temperature

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.b8028.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 2997-3000

Keyword(s):

Compressive Strength ◽

High Strength Concrete ◽

Room Temperature ◽

Elevated Temperatures ◽

High Strength ◽

Air Cooling ◽

Split Tensile Strength ◽

Strength Concrete ◽

Hardened Properties ◽

Compressive Strength Of Concrete

The High strength concrete defined as per IS 456 as the concrete having characteristic compressive strength more than 65 MPa. The concrete when subject to fire i.e. elevated temperatures loses its properties at a rapid rate. In the present investigation, ordinary vibrated concrete of M90 grade was developed as per the IS 10262. The hardened properties of concrete like compressive strength and split tensile strength were determined for concrete at ordinary temperature. The concrete specimens were subjected to elevated temperatures of 400oC, 600 oC, and 800 oC and then the specimens were brought to room temperature under different cooling regimes like air cooling and water quenching. The compressive residual strength of concrete was determined and a typical compared was made with the control specimen. The decrease in compressive strength of concrete at 800 oC was high compared to that at 400 oC.

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A Sustainable Environmental Study on Corn Cob Ash Subjected To Elevated Temperature

Current World Environment ◽

10.12944/cwe.13.1.13 ◽

2018 ◽

Vol 13 (1) ◽

pp. 144-150 ◽

Cited By ~ 2

Author(s):

Komalpreet Singh ◽

Jaspal Singh ◽

Sarvesh Kumar

Keyword(s):

Compressive Strength ◽

High Temperature ◽

Elevated Temperature ◽

Room Temperature ◽

Carbon Dioxide Emission ◽

Environmental Study ◽

Air Cooling ◽

Corn Cob ◽

Muffle Furnace ◽

Compressive Strength Of Concrete

Rapid increase in greenhouse gas induces mischievous impact on environment. In this study, carbon dioxide emission can be reduced to some extent by replacing some amount of cement with corn cob ash. The performance of concrete at high temperature was also studied. This paper investigates the effect of elevated temperature on strength property of ordinary concretes of grade M25, containing Corn Cob Ash (CCA) at various replacement levels of cement. The cube samples were subjected to high temperature of 1500C, 3000C, 4500C and 6000C for 2 hour duration in a muffle furnace. The samples were tested for compressive strength after air cooling to the room temperature. It can be seen that at normal temperature, compressive strength of the concrete decreases as the CCA content increases. The compressive strength of concrete increased significantly for all the mixes including control mix when the temperature was raised to 3000C. The recommended maximum replacement content of cement with CCA and elevated temperature was 10% and 3000C respectively.

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