A new cumulative damage rule for multilevel cyclic loading with mean stresses

1996 ◽  
Vol 75 (2) ◽  
pp. R29-R35
Author(s):  
Yu Gui-Lan ◽  
Wang Yue-Sheng ◽  
Gai Bing-Zheng
Keyword(s):  
Cyclic Loading ◽  
Cumulative Damage ◽  
Mean Stresses ◽  
Damage Rule

A Reinterpretation of the Palmgren-Miner Rule for Fatigue Life Prediction

1980 ◽  
Vol 47 (2) ◽  
pp. 324-328 ◽  
Author(s):  
Z. Hashin
Keyword(s):  
Fatigue Life ◽  
Cyclic Loading ◽  
Life Prediction ◽  
Cumulative Damage ◽  
Fatigue Life Prediction ◽  
Damage Theory ◽  
Special Case ◽  
Damage Rule

It is shown that the simple Palmgren-Miner linear cumulative damage rule is a special case of a general cumulative damage theory previously established. Predictions of lifetimes for families of multistage loadings according to the Palmgren-Miner rule and the general cumulative damage theory are compared with the aim of arriving at qualitative guidelines for applicability of the Palmgren-Miner rule in cyclic loading programs.

Cumulative damage rule under sliding wear of White metal

2003 ◽  
Vol 2003.40 (0) ◽  
pp. 315-316
Author(s):  
Yukari Tachi ◽  
Kiyoshi Tamura ◽  
Sotomi Ishihara ◽  
Takahito Goshima
Keyword(s):  
Sliding Wear ◽  
Cumulative Damage ◽  
White Metal ◽  
Damage Rule

Application of Fracture Mechanics to Determine the Remaining Lifetime of the Old Steel Bridges Decks

2015 ◽  
Vol 1111 ◽  
pp. 110-115
Author(s):  
Silvia Mihaela Hernea ◽  
Dorel Boldus ◽  
Anamaria Feier
Keyword(s):  
Fracture Mechanics ◽  
Crack Growth ◽  
Calculation Method ◽  
Bridge Deck ◽  
Steel Bridges ◽  
Cumulative Damage ◽  
Experimental Program ◽  
Steel Bridge ◽  
Classical Calculation ◽  
Damage Rule

This paper presents a procedure based on fracture mechanics to predict the evolution of cracks detected in a part of steel bridge deck, still in operation, and establishing thus remaining lifetime below a certain range of application from future traffic. It is also described an experimental program conducted on samples from available material, to determine the material factors “C” and “m” involved in Paris formula and their use in a calculation procedure for simulating crack growth detected. Finally is presented a comparison with results obtained from a classical calculation method, the cumulative damage rule of Palmergren-Miner.

scholarly journals Analysis of Cumulative Damage Characteristics of Long Spiral Belled Pile under Horizontal Cyclic Loading at Sea

2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Haian Liang ◽  
Hao Zeng ◽  
Kaiwei Cao ◽  
Chao Liu ◽  
Xinjun Cheng
Keyword(s):  
Energy Dissipation ◽  
Cyclic Loading ◽  
Power Function ◽  
Cumulative Damage ◽  
Model Parameters ◽  
Function Model ◽  
Load Amplitude ◽  
Cycle Times ◽  
Energy Dissipation Capacity ◽  
Energy Dissipation Coefficient

In order to study the cumulative damage and failure characteristics of long spiral belled pile under horizontal cyclic loading of offshore wind and waves, a series of indoor experiments on single piles under horizontal cyclic load were carried out. The cycle times as well as load amplitude at the same frequency were considered during the horizontal pseudo-static cyclic tests. On the basis of the distribution of pile deflection, bending moment, and Earth pressure around the pile, the pile-soil interaction was comprehensively discussed. The cumulative energy dissipation characteristics were introduced to describe the damage of test piles. Meanwhile, the effects of load amplitude and cycle times on the cumulative damage of long spiral belled piles were discussed. A power function model for energy dissipation coefficient prediction under multi-stage cyclic load was proposed. The results show that the horizontal peak bearing capacity of long spiral belled pile is increased by 57.2% and 40.4%, respectively, as compared with the straight pile and belled pile under the same conditions. The horizontal displacement mainly occurs at the upper part of the pile. Under the condition of limited cyclic times, the load amplitude has more significant effect on the bearing characteristics of the long spiral belled pile. In contrast to the straight pile and belled pile, the long spiral belled pile has better energy dissipation capacity, and the rank of the energy dissipation capacity of these three piles is long spiral belled pile > belled pile > straight pile. The power function model can well reflect the cumulative damage characteristics of long spiral belled pile under horizontal cyclic loading, and there is a good linear relationship between power function model parameters and load amplitude. The energy dissipation coefficient of long spiral belled pile with diverse cycle times at different mechanical stages of test pile is analysed. Then, the recommended power function model parameters according to different failure stages are proposed. The verification example indicates that the prediction results are close to the measured values with a calculation error of 22%. The prediction model can provide a certain reference for the application of long spiral belled pile in marine structures.

Statistical Cumulative Damage Theory for Fatigue Life Prediction

1983 ◽  
Vol 50 (3) ◽  
pp. 571-579 ◽  
Author(s):  
Z. Hashin
Keyword(s):  
Cyclic Loading ◽  
Life Prediction ◽  
Cumulative Damage ◽  
Fatigue Life Prediction ◽  
Two Stage ◽  
Fatigue Lifetime ◽  
Damage Theory ◽  
Log Normal ◽  
Log Normal Distribution ◽  
Usual Interpretation

A statistical cumulative damage theory is developed with the purpose of prediction of mean, standard deviation and probability density of fatigue lifetime of randomly variable specimens subjected to the same deterministic cyclic loading program. The theory requires availability of a deterministic cumulative damage theory for ideal nonvariable specimens, called clones. Detailed analysis is given for two-stage cyclic loading based on a previously developed deterministic cumulative damage theory and log-normal distribution of S—N curve lifetimes. Results indicate that the usual interpretation of deterministic cumulative damage theory in terms of means of lifetimes is not valid for significant scatter. Preliminary experimental results for two-stage loading are compared with analytical predictions.

Corrosion mechanism and fatigue behavior of 2A70-T6 aluminum alloy under alternating corrosion and fatigue

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lei Fu ◽  
Hui Li ◽  
Li Lin ◽  
Qingyuan Wang ◽  
Qi Fan ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Fatigue Life ◽  
Corrosion Fatigue ◽  
Intergranular Corrosion ◽  
Fatigue Behavior ◽  
Cumulative Damage ◽  
Corrosion Mechanism ◽  
Corrosive Environment ◽  
Content Type ◽  
Damage Rule

Purpose Most supersonic aircraft were manufactured using 2A70 aluminum alloy. The purpose of this paper is to study the corrosion mechanism and fatigue behavior of an aircraft in a semi-industrial atmospheric corrosive environment, alternating effects of corrosion and fatigue were used to simulate the aircraft’s ground parking corrosion and air flight fatigue. Design/methodology/approach For this purpose, the aluminum alloy samples were subjected to pre-corrosion and alternating corrosion-fatigue experiments. The failure mechanisms of corrosion and corrosion fatigue were analyzed using microscopic characterization methods of electrochemical testing, X-ray diffraction and scanning electron microscopy. Miner’s linear cumulative damage rule was used to predict the fatigue life of aluminum alloy and to obtain its safe fatigue life. Findings The results showed that the corrosion damage caused by the corrosive environment was gradually connected by pitting pits to form denudation pits along grain boundaries. The deep excavation of chloride ions and the presence of intergranular copper-rich phases result in severe intergranular corrosion morphology. During cyclic loading, alternating hardening and softening occurred. The stress concentration caused by surface pitting pits and denudation pits initiated fatigue cracks at intergranular corrosion products. At the same time, the initiation of multiple fatigue crack sources was caused by the corrosion environment and the morphology of the transient fracture zone was also changed, but the crack propagation rate was not basically affected. The polarization curve and impedance analysis results showed that the corrosion rate increases first, decreases and then increases. Fatigue failure behavior was directly related to micro characteristics such as corrosion pits and microcracks. Originality/value In this research, alternating effects of corrosion and fatigue were used to simulate the aircraft’s ground parking corrosion and air flight fatigue. To study the corrosion mechanism and fatigue behavior of an aircraft in a semi-industrial atmospheric corrosive environment, the Miner’s linear cumulative damage rule was used to predict the fatigue life of aluminum alloy and to obtain its safe fatigue life.

Investigation Into Cumulative Damage Rules to Predict Fretting Fatigue Life of Ti-6Al-4V Under Two-Level Block Loading Condition1

2003 ◽  
Vol 125 (3) ◽  
pp. 315-323 ◽  
Author(s):  
O. Jin ◽  
H. Lee ◽  
S. Mall
Keyword(s):  
Stress Amplitude ◽  
Fatigue Behavior ◽  
Fretting Fatigue ◽  
Fatigue Tests ◽  
Cumulative Damage ◽  
Order Effects ◽  
Block Loading ◽  
Crack Growth Rates ◽  
Damage Rule ◽  
Repeated Block

The effects of variable amplitude loading on fretting fatigue behavior of titanium alloy, Ti-6Al-4V were examined. Fretting fatigue tests were carried out under constant stress amplitude and three different two-level block loading conditions: high-low (Hi-Lo), low-high (Lo-Hi), and repeated block of high and low stress amplitudes. The damage fractions and fretting fatigue lives were estimated by linear and non-linear cumulative damage rules. Damage curve analysis (DCA) and double linear damage rule (DLDR) were capable to account for the loading order effects in Hi-Lo and Lo-Hi loadings. In addition, the predictions by DCA and DLDR were better than that by linear damage rule (LDR). Besides its simplicity of implementation, LDR was also capable of estimating failure lives reasonably well. Repeated two-level block loading resulted in shorter lives and lower fretting fatigue limit compared to those under constant amplitude loading. The degree of reduction in fretting fatigue lives and fatigue strength depended on the ratio of cycles at lower stress amplitude to that at higher stress amplitude. Fracture surface of specimens subjected to Hi-Lo and repeated block loading showed the clear evidence of change in stress amplitude of applied load. Especially, the repeated two-level block loading resulted in characteristic markers which reflected change in crack growth rates corresponding to different stress amplitudes.

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