Analytical Life-Prediction Model for RC Beams Strengthened with Externally Bonded FRP Laminates under Flexural Fatigue Loading

2018 ◽  
Vol 22 (6) ◽  
pp. 06018002 ◽  
Author(s):  
Mohammad Al-Qaralleh ◽  
Houssam Toutanji
Keyword(s):  
Prediction Model ◽  
Life Prediction ◽  
Fatigue Loading ◽  
Rc Beams ◽  
Flexural Fatigue ◽  
Externally Bonded ◽  
Life Prediction Model

Life Prediction and Stiffness Degradation Modeling of Glass/Epoxy Composites Subjected to Flexural Fatigue Loading

2016 ◽  
Author(s):  
Vinod B. Suryawanshi ◽  
Evan T. Kimbro ◽  
Ajit D. Kelkar
Keyword(s):  
Fatigue Life ◽  
Prediction Model ◽  
Life Prediction ◽  
Epoxy Composite ◽  
Fatigue Loading ◽  
Stiffness Degradation ◽  
Degradation Model ◽  
Flexural Fatigue ◽  
Plain Weave ◽  
Life Prediction Model

Textile composite are extensively used as structural materials for automotive, aerospace, energy, transportation and construction applications. During their service life these structures are subjected to different types of static and cyclic loading. For structural health monitoring of these structures, it is important to know the fatigue life and damage occurred at any stage of the life of the structure. Fatigue life is generally estimated using suitable life prediction model, while fatigue damage can be predicted by monitoring measurable damage parameters such as stiffness and strength. Two mathematical models namely fatigue life prediction model and stiffness degradation model are proposed for plain weave glass/epoxy composite subjected to flexural fatigue loading. Three different functions namely linear, exponential and sigmoid are evaluated to represent S-N diagram for plain weave glass/epoxy composite. Using predicted fatigue life along with initial modulus as inputs, the stiffness degradation model can predict residual stiffness at any stage of the fatigue loading life cycle. Logarithmic function used to represent stiffness degradation in the model is derived by inverting Boltzmann sigmoid function. The results of both, fatigue life model and stiffness degradation model were found to be in good agreement with those of the experimental results.

scholarly journals Fatigue Life Prediction of Reinforced Concrete Beams Strengthened with CFRP: Study Based on an Accumulative Damage Model

Polymers ◽  
2019 ◽  
Vol 11 (1) ◽  
pp. 130 ◽  
Author(s):  
Xin-Yan Guo ◽  
Yi-Lin Wang ◽  
Pei-Yan Huang ◽  
Xiao-Hong Zheng ◽  
Yi Yang
Keyword(s):  
Reinforced Concrete ◽  
Fatigue Life ◽  
Carbon Fiber ◽  
Prediction Model ◽  
Life Prediction ◽  
Damage Model ◽  
Fatigue Life Prediction ◽  
Rc Beams ◽  
Rc Structures ◽  
Life Prediction Model

With the prestressed carbon fiber reinforced polymer (CFRP) strengthening technique widely used in reinforced concrete (RC) structures, it is more and more important to study the fatigue performance of RC structures. Since the fracture of a tensile steel bar at the main cracked section is the leading reason for the failure of RC beams reinforced by prestressed CFRP, a fatigue life prediction model of RC beams reinforced by prestressed CFRP was developed based on an accumulative damage model. Moreover, gradual degradation of the performance of the concrete was considered in the fatigue life prediction model. An experimental study was also conducted to research the fatigue behavior of RC beams reinforced by prestressed or non-prestressed carbon fiber laminate (CFL). During the tests, fatigue crack patterns were captured using a digital image correlation (DIC) technique, and the fatigue lives of a total of 30 beams were recorded. The results showed that the predicted main crack propagation curves and the fatigue lives were close to the experimental data. This study also exhibited that the prestressed CFRP could reduce the stress of main steel bars in RC beams and effectively improve the fatigue performance of the RC beams.

scholarly journals Life Prediction Model of Mineral Admixture Cement Based-Materials under Early Age CO2-Erosion

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 413
Author(s):  
Saisai Wang ◽  
Jian Chen ◽  
Xiaodong Wen
Keyword(s):  
Prediction Model ◽  
Life Prediction ◽  
Experimental Tests ◽  
Mineral Admixture ◽  
Model Parameters ◽  
Influence Coefficient ◽  
Test Pieces ◽  
Cement Based Materials ◽  
Particle Group ◽  
Life Prediction Model

Most of the existing models of structural life prediction in early carbonized environment are based on accelerated erosion after standard 28 days of cement-based materials, while cement-based materials in actual engineering are often exposed to air too early. These result in large predictions of the life expectancy of mineral-admixture cement-based materials under early CO2-erosion and affecting the safe use of structures. To this end, different types of mineral doped cement-based material test pieces are formed, and early CO2-erosion experimental tests are carried out. On the basis of the analysis of the existing model, the influence coefficient of CO2-erosion of the mineral admixture Km is introduced, the relevant function is given, and the life prediction model of the mineral admixture cement-based material under the early CO2-erosion is established and the model parameters are determined by using the particle group algorithm (PSO). It has good engineering applicability and guiding significance.

The construction of the life prediction model of 1N and 4N monopropellant thrusters

2013 ◽  
Author(s):  
Go Fujii ◽  
Daisuke Goto ◽  
Hideshi Kagawa ◽  
Shingo Murayama ◽  
Kenichi Kajiwara ◽  
...  
Keyword(s):  
Prediction Model ◽  
Life Prediction ◽  
Life Prediction Model

Wire Fatigue Models for Power Electronic Modules

2003 ◽  
Author(s):  
Karumbu Nathan Meyyappan ◽  
Peter Hansen ◽  
Patrick McCluskey
Keyword(s):  
Prediction Model ◽  
Life Prediction ◽  
Damage Model ◽  
Cyclic Strain ◽  
Temperature Cycling ◽  
Transformation Model ◽  
Time To Failure ◽  
Flexural Failure ◽  
The Wire ◽  
Life Prediction Model

This paper presents two, semi-analytical, physics-of-failure based life prediction model formulations for flexural failure of wires ultrasonically wedge bonded to pads at different heights. The life prediction model consists of a load transformation model and a damage model. The load transformation model determines the cyclic strain is created by a change in wire curvature at the heel of the wire resulting from expansion of the wire and displacement of the frame. The damage model calculates the life based on the strain cycle magnitude and the elastic-plastic fatigue response of the wire. The first formulation provides quick calculation of the time to failure for a wire of known geometry. The second formulation optimizes the wire geometry for maximum time to failure. These model formulations support virtual qualification of power modules where wire flexural fatigue is a dominant failure mechanism. The model has been validated using temperature cycling test results.

Fatigue Life Prediction of Buckling String with Cracks in Horizontal Wells of Mining Engineering

2012 ◽  
Vol 577 ◽  
pp. 127-131 ◽  
Author(s):  
Peng Wang ◽  
Tie Yan ◽  
Xue Liang Bi ◽  
Shi Hui Sun
Keyword(s):  
Fatigue Life ◽  
Prediction Model ◽  
Life Prediction ◽  
Horizontal Well ◽  
Drill Pipe ◽  
Prediction Method ◽  
Drill String ◽  
Fatigue Life Prediction ◽  
Mining Engineering ◽  
Life Prediction Model

Fatigue damage in the rotating drill pipe in the horizontal well of mining engineering is usually resulted from cyclic bending stresses caused by the rotation of the pipe especially when it is passing through curved sections or horizontal sections. This paper studies fatigue life prediction method of rotating drill pipe which is considering initial crack in horizontal well of mining engineering. Forman fatigue life prediction model which considering stress ratio is used to predict drill string fatigue life and the corresponding software has been written. The program can be used to calculate the stress of down hole assembly, can predict stress and alternating load in the process of rotating-on bottom. Therefore, establishing buckling string fatigue life prediction model with cracks can be a good reference to both operation and monitor of the drill pipe for mining engineering.

A LIFE PREDICTION MODEL OF THERMAL BARRIER COATINGS

2010 ◽  
Vol 24 (15n16) ◽  
pp. 3161-3166 ◽  
Author(s):  
LIYONG NI ◽  
CHAO LIU ◽  
CHUNGEN ZHOU
Keyword(s):  
Crack Propagation ◽  
Prediction Model ◽  
Thermal Barrier Coatings ◽  
Life Prediction ◽  
Crack Propagation Rate ◽  
Thermal Barrier ◽  
Critical Crack ◽  
Critical Crack Length ◽  
Barrier Coatings ◽  
Life Prediction Model

The durability and reliability of thermal barrier coatings(TBCs) have become a major concern of hot-section components due to lack of a reliable life prediction model. In this paper, it is found that the failure location of TBCs is at the TBC/TGO interface by a sequence of crack propagation and coalescence process. The critical crack length of failure samples is 8.8mm. The crack propagation rate is 3-10µm/cycle at the beginning and increases largely to 40µm/cycle near coating failure. A life prediction model based a simple fracture mechanics approach is proposed.

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