Development of fatigue test method and improvement of fatigue life by new functional steel plates for welding of trough rib and deck plate of orthotropic decks

2013 ◽  
Vol 13 (1) ◽  
pp. 191-197 ◽  
Author(s):  
Noboru Konda ◽  
Masaru Nishio ◽  
Mitsuru Ichimiya ◽  
Toshihiro Kasugai ◽  
Shogo Kiyokawa
Author(s):  
Waleed Abdelaziz Zeiada ◽  
Padmini P. Gudipudi ◽  
B. Shane Underwood ◽  
Mena I. Souliman

Fatigue cracking is one of the most critical types of distress in asphalt pavements and is due to actions of repetitive traffic loading over time. The fatigue life of asphalt concrete is often estimated from laboratory experiments where the performance depends directly on the test method, loading conditions, temperature, rest period, and aging in addition to the composition and properties of the mixture itself. The uniaxial fatigue test has become a popular method for developing constitutive models that describe the fatigue behavior of asphalt concrete mixture owing to the uniform states of stress across the specimen section. This study investigates the effect of the loading waveform (sinusoidal versus haversine) and rest period (continuous versus intermittent) on the laboratory fatigue life of asphalt concrete mixtures. The fatigue analysis was performed using the simplified viscoelastic continuum damage (S-VECD) approach where the damage characteristic (C-S) curves were established for all the cases, and then used to estimate the fatigue laws through simulated predictions. The proposed uniaxial fatigue test and analysis method were able to determine the fatigue life relationships of asphalt concrete mixture at different waveform and rest period conditions with a reduced testing time compared to other traditional testing and analysis methods. Overall, both rest period and waveform pattern were found to affect the laboratory fatigue life of asphalt concrete mixture. Model predictions show that pulse-rest loading yields an equivalent fatigue life to continuous loading at strain values that are approximately four times greater.


2010 ◽  
Vol 34-35 ◽  
pp. 595-599
Author(s):  
Nan Cong ◽  
Xun Chen ◽  
Jian Zhong Shang ◽  
Ke Shan Liang

Non-Structural road driving test is a key part of fatigue and durability tests for vehicles such as the construction machines and ATVs. Combining a theoretic road-tyre dynamic model with some real vehicle design parameters, the responses of the wheel axle under different non-structural road conditions were estimated conveniently. The responses can be taken as inputs for a virtual test-rig simulation, and the responses of every part on the test object are obtained separately. Fatigue life is predicted under the finite element circumstance, and the reliability and durability are concluded. Comparing with the real road-driving test, the virtual fatigue test method above can significantly reduce the test period. This method is used to predict the fatigue life of the rear axle-housing in construction machines, the accuracy of the method is verified by a corresponding real bench test.


2012 ◽  
Vol 433-440 ◽  
pp. 3-8 ◽  
Author(s):  
Wei Mao Zhao ◽  
Wei Zheng Zhang

Thermal fatigue tests were conducted on diesel engine cylinder heads of gray cast iron HT250 with conductive heating fatigue test rig. The thermal fatigue life is affected by the maximum temperature and heating time. The relationship between thermal fatigue life, temperature, and heating time was researched. Thermal fatigue life prediction model was derived from classical energy fatigue criteria. The parameters of the model were obtained from the results of the thermal fatigue test. The model and thermal fatigue test method are suitable for cylinder heads of cast irons and cast aluminum alloys, the parameters should be fixed by thermal fatigue test.


Author(s):  
Choongryeong Lee ◽  
Hyun-Yong Jeong

A purpose of this paper is to analyze the effects of material properties and design of a jig on fatigue test results of dental implants. An implant fatigue test method is specified in ISO14801 [1], but it is not described well about the fatigue test jig. The jig of ISO14801 has to firmly hold the fixture, and the elastic modulus of the jig should be more than 3 GPa. These requirements are not sufficient enough to represent the dental implant in the jawbone because the fixture is osseointegrated in the jawbone that is made up with the cortical bone and cancellous bone. In this paper three different materials were used for the jig, and two different fixation methods to hold the fixture were examined in several FE (Finite Element) simulations and fatigue tests. From the simulation and test results, the effects of material properties and design of the jig were evaluated in the light of fatigue life of dental implants.


Author(s):  
Dong-Wook Cha ◽  
Hyun-Yong Jeong

Crack growth in tires plays an important role in the durability of tires, and it is necessary to evaluate the characteristics of crack growth accurately. Since a tire is subjected to interlaminar shear stresses, a Mode III fatigue test method was developed. The fatigue life of three different tire specimens was measured by using the fatigue test method. Based on the fatigue test results, the effects of heat aging, temperature and belt stiffness on crack growth were analyzed.


2016 ◽  
Vol 16 (1) ◽  
pp. 61-68 ◽  
Author(s):  
Yi-Chueh Shieh ◽  
Hsuan-Yu Lin ◽  
Wensyang Hsu ◽  
Yu-Hsin Lin

Sign in / Sign up

Export Citation Format

Share Document