The Experts below are selected from a list of 19533 Experts worldwide ranked by ideXlab platform
Yang Deng - One of the best experts on this subject based on the ideXlab platform.
-
Fatigue Reliability assessment for orthotropic steel decks based on long-term strain monitoring
Sensors (Switzerland), 2018Co-Authors: Yang Deng, Aiqun Li, Dongming FengAbstract:A time-dependent Fatigue Reliability assessment approach is proposed for welded details of orthotropic steel decks (OSDs) using long-term strain monitoring data. The Fatigue Reliability limit function of the welded details is established based on the Eurocode specifications. Depending on the distribution characteristics of the measured daily equivalent stress range, either the lognormal distribution or Gaussian mixture model (GMM) is selected to quantify its uncertainty. Subsequently, the Fatigue Reliability can be calculated using either an explicit formula or the Monte Carlo method. This proposed approach is applied for the Fatigue Reliability evaluation of two rib-to-deck and two rib-to-rib welded Fatigue details of an in-service suspension bridge. The results show that the Reliability indices decrease significantly with bridge’s service life. Except for a rib-to-deck detail, all other three welded details cannot meet the target Fatigue Reliability during this bridge’s 100-year service life. The proposed approach can help bridge owners and operators make informed decisions regarding maintenance and repair of potential Fatigue cracks.
-
Fatigue Reliability assessment for orthotropic steel deck details under traffic flow and temperature loading
Engineering Failure Analysis, 2017Co-Authors: Haiping Zhang, Yang Deng, Nan Jiang, Naiwei LuAbstract:Abstract A new Fatigue Reliability assessment function which takes into account the vehicle and temperature loadings has been developed in this study. The vehicle and temperature loadings are important parameters as they can cause Fatigue failure of the welds in a steel box girder. The temperature affects the traffic loading effect by changing the elastic modulus of asphalt pavement. The effect of the temperature difference has been considered based on the measured data and the finite element analysis. Linear regression equations between the equivalent stress and the temperature for different vehicle types have been developed. Using the thermal stress analysis and the rain-flow counting method, the temperature difference Fatigue stress spectrum has been determined. Further, a limit equation for the Fatigue Reliability assessment, which takes into account both the vehicle and temperature loadings, has been developed. Finally, the effects of the temperature and the traffic growth rate on the Fatigue Reliability of two welding types of Nan-xi Yangtze River Suspension Bridge have been assessed.
-
Fatigue Reliability Assessment of Orthotropic Bridge Decks under Stochastic Truck Loading
Shock and Vibration, 2016Co-Authors: Yang Liu, Xinhui Xiao, Yang DengAbstract:A steady traffic growth has posed a threat to the Fatigue safety of existing bridges. Uncertainties in traffic flows add to the challenge of an accurate Fatigue safety assessment. This article utilizes a stochastic traffic load model to evaluate the Fatigue Reliability of orthotropic steel bridge decks. The traffic load model is simulated by site-specific weigh-in-motion measurements. A response surface method is presented to solve the time-consuming problem caused by hotspot stress simulations in the finite element model. Applications of the stochastic traffic load model for probabilistic modeling and Fatigue Reliability assessment are demonstrated in the case study of a steel box-girder bridge. Numerical results indicate that the growth rate of the gross vehicle weight leads to a rapid decrease of the Fatigue Reliability in comparison to the traffic volume growth. Even though the traffic volume growth is rapid, the control of overloaded trucks in comparison to the traffic volume is an effective way to ensure the Fatigue safety of the steel bridges.
-
Fatigue Reliability assessment for bridge welded details using long term monitoring data
Science China-technological Sciences, 2011Co-Authors: Yang Deng, Youliang Ding, Guangdong ZhouAbstract:A Reliability assessment method of Fatigue life based on the long-term monitoring data is developed for welded details in steel box girder, and the application research is presented with examples of welded rib-to-deck details in Runyang Bridges. Firstly the Fatigue damage limit-state function is established based on S-N curves and Miner’s rule, and the probability distribution characteristics of the coefficients in the function are discussed in detail. The uncertainties in Fatigue loading effects are mainly studied based on long-term monitoring data. In the traditional studies, only the uncertainty of equivalent stress range is considered in Fatigue Reliability assessment. However, stress cycle number is also treated as a random variable in this paper because we know traffic flow every day differs in a thousand ways. Then the optimization method is employed to calculate the Fatigue Reliability. After studying the changing law of the Reliability indices with time and the effect of the randomness of stress cycle number on Reliability, the effect of the traffic growth on the Reliability is studied. This study shows that the uncertainty in the Fatigue life of the welded details can be well studied based on structural health monitoring, so it is necessary to carry out long-term strain monitoring of the welded details for accurate Fatigue Reliability assessment during the whole service period.
Dongming Feng - One of the best experts on this subject based on the ideXlab platform.
-
Fatigue Reliability assessment for orthotropic steel decks based on long-term strain monitoring
Sensors (Switzerland), 2018Co-Authors: Yang Deng, Aiqun Li, Dongming FengAbstract:A time-dependent Fatigue Reliability assessment approach is proposed for welded details of orthotropic steel decks (OSDs) using long-term strain monitoring data. The Fatigue Reliability limit function of the welded details is established based on the Eurocode specifications. Depending on the distribution characteristics of the measured daily equivalent stress range, either the lognormal distribution or Gaussian mixture model (GMM) is selected to quantify its uncertainty. Subsequently, the Fatigue Reliability can be calculated using either an explicit formula or the Monte Carlo method. This proposed approach is applied for the Fatigue Reliability evaluation of two rib-to-deck and two rib-to-rib welded Fatigue details of an in-service suspension bridge. The results show that the Reliability indices decrease significantly with bridge’s service life. Except for a rib-to-deck detail, all other three welded details cannot meet the target Fatigue Reliability during this bridge’s 100-year service life. The proposed approach can help bridge owners and operators make informed decisions regarding maintenance and repair of potential Fatigue cracks.
Jun Li - One of the best experts on this subject based on the ideXlab platform.
-
Fatigue Reliability evaluation of deck to rib welded joints in osd considering stochastic traffic load and welding residual stress
International Journal of Fatigue, 2018Co-Authors: Qinghua Zhang, Jun LiAbstract:Abstract The welding residual stress has a prominent contribution to the Fatigue damage in deck-to-rib joints of orthotropic steel decks. To estimate the Fatigue Reliability of deck-to-rib joints with the combined effect of welding residual stress and stochastic traffic flow, a simplified mechanical model is employed to analyze the combined effect of welding residual stress and vehicle-induced stress. The Fatigue Reliability assessment is conducted by considering the increases of both the traffic flow and the gross vehicle weight with the strain energy density based method. The results demonstrate that the obtained stochastic traffic flow model agrees well with that measured from the weigh-in-motion system, validating the accuracy of the established stochastic traffic flow model for the Fatigue Reliability analysis. From the calculated Fatigue Reliability indices with or without the effect of welding residual stress, it can be concluded that the welding residual stress has a prominent negative influence on the Fatigue resistance. The effect of the increase of the gross vehicle weight is more significant than that with the increase of the traffic flow on the Fatigue Reliability, demonstrating that the growth of the gross vehicle weight has a more detrimental impact on the Fatigue service life.
Qinghua Zhang - One of the best experts on this subject based on the ideXlab platform.
-
Fatigue Reliability evaluation of deck to rib welded joints in osd considering stochastic traffic load and welding residual stress
International Journal of Fatigue, 2018Co-Authors: Qinghua Zhang, Jun LiAbstract:Abstract The welding residual stress has a prominent contribution to the Fatigue damage in deck-to-rib joints of orthotropic steel decks. To estimate the Fatigue Reliability of deck-to-rib joints with the combined effect of welding residual stress and stochastic traffic flow, a simplified mechanical model is employed to analyze the combined effect of welding residual stress and vehicle-induced stress. The Fatigue Reliability assessment is conducted by considering the increases of both the traffic flow and the gross vehicle weight with the strain energy density based method. The results demonstrate that the obtained stochastic traffic flow model agrees well with that measured from the weigh-in-motion system, validating the accuracy of the established stochastic traffic flow model for the Fatigue Reliability analysis. From the calculated Fatigue Reliability indices with or without the effect of welding residual stress, it can be concluded that the welding residual stress has a prominent negative influence on the Fatigue resistance. The effect of the increase of the gross vehicle weight is more significant than that with the increase of the traffic flow on the Fatigue Reliability, demonstrating that the growth of the gross vehicle weight has a more detrimental impact on the Fatigue service life.
X M Wang - One of the best experts on this subject based on the ideXlab platform.
-
shms based Fatigue Reliability analysis of multiloading suspension bridges
Journal of Structural Engineering-asce, 2012Co-Authors: Zhiwei Che, X M WangAbstract:Long-span suspension bridges carrying both highway and railway have been built in wind-prone regions. The estimation of Fatigue damage of such bridges under the long-term combined action of railway, highway, and wind loading represents a challenging task in consideration of randomness in multiple types of loading. This study presents a framework for Fatigue Reliability analysis of multiloading long-span suspension bridges equipped with structural health monitoring systems (SHMS), and the Tsing Ma suspension bridge in Hong Kong is taken as a case study. A limit-state function in the daily sum of m-power stress ranges is first defined for Fatigue Reliability analysis. Probabilistic models of railway, highway, and wind loading are established on the basis of the measurement data acquired from the SHMS. The daily stochastic stress responses induced by the multiple types of loading are simulated at the Fatigue-critical locations of the bridge deck by using the finite-element method and Monte Carlo simulation (...
