scholarly journals A New Combination Method of Temperature and Vehicle Load Effects Based on SHM Data

2012 ◽  
Vol 5 ◽  
pp. 157-161 ◽  
Author(s):  
Zi Jian Wang ◽  
Rong Pan Hu ◽  
Shun Long Li
Keyword(s):  
Service Life ◽  
Extreme Values ◽  
Generalized Pareto Distribution ◽  
Rectangular Pulse ◽  
Combination Method ◽  
New Combination ◽  
Load Effect ◽  
Mean Values ◽  
Vehicle Load ◽  
Load Effects

When more than one load act on a structure, the combination of the load effects should be considered, especially for which are variant in time and in space. A new method to calculate the combination of two different loads effects as well as to predict the extreme value distributions in the subsequent service life is proposed. The loads discussed in this paper are two main loads acting on the cable-stayed bridge: the temperature and vehicle load, which can be modeled as rectangular pulse process and filtered Poisson process respectively. Firstly, truncated distributions of the two load effects are depicted using the monitoring data of Nanjing 3rd Yangtze River Bridge. The generalized Pareto distribution fits well to the upper tails of the vehicle load effect and the mean values of the temperature load effect in an hour follows a two weighted normal distribution. Then the combination of the two load effects as well as the prediction of extreme values in the subsequent service life can be calculated. In the end, the results obtained through the proposed method are compared with the observed value of the bridge.

scholarly journals Component Combination Rules of Wind Load Effects of Building Structures

2020 ◽  
Vol 10 (24) ◽  
pp. 8775
Author(s):  
Haiwei Guan ◽  
Yuji Tian
Keyword(s):  
Extreme Values ◽  
Simulation Method ◽  
Wind Load ◽  
Combination Method ◽  
Wind Effect ◽  
Building Structures ◽  
Combination Rules ◽  
Load Effect ◽  
Mean Values ◽  
Standard Deviations

Under the action of the same wind azimuth, the extreme values of the wind load effect components of building structures are generated in the along-wind, cross-wind, vertical, and torsional directions. In designing the wind-resistant structure, the extreme values of effect components need to be combined to determine the internal force envelope values of members. Complete quadratic combination (CQC) and Turkstra combination rules are often used to determine the combination value of extreme values of wind effect components. The extreme probability distribution expressions of the CQC, and the Turkstra and approximate rules, are derived. The simplified combination Equations and combination coefficients of the CQC and Turkstra approximate rules are proposed in this paper. We use the combination Equations and Monte Carlo simulation method to analyze the accuracy of Turkstra and its approximate rules. The results show that the combination extreme is associated with the correlation coefficients, mean values, ratios of standard deviations, and fluctuating extremes of effect components. The errors between Turkstra and its approximate rules are small when load effect components show a positive correlation. The errors are largest when the standard deviations of components are equal. Our research results provide a theoretical basis for the combination method of wind load effect components of building structures.

Monte Carlo Prediction of the Extreme Values of the Combined Load Effect and Semi-Probabilistic Design of Ocean-Going Ships

2013 ◽  
Author(s):  
Wenbo Huang ◽  
Ying Xiao
Keyword(s):  
Monte Carlo ◽  
Extreme Values ◽  
Empirical Distribution ◽  
Extreme Value Distribution ◽  
Distribution Model ◽  
Wave Load ◽  
Load Effect ◽  
Combined Load ◽  
Load Combination ◽  
Load Effects

Based on Poisson models, the Monte Carlo simulation of the combined still-water and wave load effects is carried out to estimate extreme values of the combined load effects of oceangoing ships. The extreme values predicted are compared with those based on the theoretical methods. The numerical analyses show that the results based on the two methods agree with very well. Moreover, the empirical distribution of the combine extreme values simulated and numerical theoretical distribution based on a load combination analysis can both be well fitted to an analytical extreme value distribution model of Type II. Besides, a strength model of a ship hull beam is developed based on the fatigue analyses. Finally, with the models developed for load effect and strength, the simplified reliability analyses are carried out for an ocean going ship.

The Highway Bridge Load Subentry Coefficient and Their Combination Effect Comparative Analysis

2012 ◽  
Vol 239-240 ◽  
pp. 654-660
Author(s):  
Dong Dang ◽  
Jing Sun
Keyword(s):  
Highway Bridges ◽  
Highway Bridge ◽  
Combination Effect ◽  
Safety Factors ◽  
Load Effect ◽  
Vehicle Load ◽  
The World ◽  
Load Effects ◽  
Partial Safety Factors ◽  
Chinese Standard

This paper takes the short and medium span bridges as examples to evaluate position of Chinese load effect partial safety factors and their combination effect. First, to get the new partial safety factors of vehicle load effects, this paper conducted a survey of the short and medium span bridges ,distinguished the similarities and differences between the standard in highway bridges from different countries and confirmed the reasonable position of Chinese standard in the world.

scholarly journals Evaluating Life Cycle of Buildings Using an Integrated Approach Based on Quantitative-Qualitative and Simplified Best-Worst Methods (QQM-SBWM)

2021 ◽  
Vol 13 (8) ◽  
pp. 4487
Author(s):  
Maghsoud Amiri ◽  
Mohammad Hashemi-Tabatabaei ◽  
Mohammad Ghahremanloo ◽  
Mehdi Keshavarz-Ghorabaee ◽  
Edmundas Kazimieras Zavadskas ◽  
...  
Keyword(s):  
Life Cycle ◽  
Computer Software ◽  
Integrated Approach ◽  
Comfort Level ◽  
Combination Method ◽  
New Combination ◽  
Numerical Examples ◽  
Environmental Consequences ◽  
Time Required

Evaluating the life cycle of buildings is a valuable tool for assessing sustainability and analyzing environmental consequences throughout the construction operations of buildings. In this study, in order to determine the importance of building life cycle evaluation indicators, a new combination method was used based on a quantitative-qualitative method (QQM) and a simplified best-worst method (SBWM). The SBWM method was used because it simplifies BWM calculations and does not require solving complex mathematical models. Reducing the time required to perform calculations and eliminating the need for complicated computer software are among the advantages of the proposed method. The QQM method has also been used due to its ability to evaluate quantitative and qualitative criteria simultaneously. The feasibility and applicability of the SBWM were examined using three numerical examples and a case study, and the results were evaluated. The results of the case study showed that the criteria of the estimated cost, comfort level, and basic floor area were, in order, the most important criteria among the others. The results of the numerical examples and the case study showed that the proposed method had a lower total deviation (TD) compared to the basic BWM. Sensitivity analysis results also confirmed that the proposed approach has a high degree of robustness for ranking and weighting criteria.

Vehicle Load Effect of Long-Span Bridges

2015 ◽  
Vol 2481 (1) ◽  
pp. 132-139 ◽  
Author(s):  
Jun Wu ◽  
Fei Yang ◽  
Wanshui Han ◽  
Liujie Wu ◽  
Qiang Xiao ◽  
...  
Keyword(s):  
Load Effect ◽  
Long Span Bridges ◽  
Long Span ◽  
Vehicle Load

Response of a CALM Buoy Moored Vessel in Squall Condition

2016 ◽  
Author(s):  
Mark Paalvast ◽  
Jelte Kymmell ◽  
Ward Gorter ◽  
Alison Brown
Keyword(s):  
Extreme Values ◽  
Generalized Pareto Distribution ◽  
Generalized Pareto ◽  
Benchmark Database ◽  
Peak Over Threshold ◽  
Vessel Response ◽  
Design Loads ◽  
Novel Method ◽  
Selection For ◽  
Reliable Design

This paper reviews the response of a hawser moored vessel to squalls and addresses a novel method for obtaining statistically reliable design loads. Industry paradigms related to squall selection for analysis input are reviewed and renewed. A benchmark database consisting of more than 15,000 unique squall-wave-current induced extreme values enables the validation of a range of less computationally demanding analysis and squall selection methods. Extreme values are extrapolated to a design value using a Peak Over Threshold (POT) method to fit a Generalized Pareto Distribution (GPD). The influence of associated metocean conditions and squall characteristics on the vessel response is presented. By means of bootstrapping a satisfactory population size for design purposes is studied. The findings challenge common design practices currently employed throughout the industry.

Abnormal Wave-Induced Load Effects in Ship Structures

2008 ◽  
Vol 52 (01) ◽  
pp. 30-44 ◽  
Author(s):  
C. Guedes Soares ◽  
N. Fonseca ◽  
R. Pascoal
Keyword(s):  
Extreme Values ◽  
Time History ◽  
Design Criterion ◽  
Freak Waves ◽  
Reference Design ◽  
Load Effects ◽  
Central North Sea ◽  
Wave Induced ◽  
First Time

The paper presents an approach to determine the global load effects induced on shif structures by abnormal, freak, or episodic waves. It refers to the present procedure of determining extreme values of wave-induced responses, including the recent advances of adopting time series of wave elevation as reference design conditions t calculate the wave-induced structural loads on ships in heavy weather. It is show how this procedure can be extended to account for abnormal or episodic waves Reference is made to what is presently known about abnormal or freak waves showing that although it is possible to determine the loads induced by these wave in floating and fixed structures, the present knowledge about the probability of occurrence of these waves is not enough to allow a wave design criterion to be defined in a way consistent with the present probabilistic approaches. However, it is suggested that at the present stage of knowledge it is possible to determine the load induced by abnormal waves similar to ones that have been measured at various ocean locations and that are thus realistic; a method is described to perform such calculations. Although this information cannot replace the wave-induced loads calculated with the presently established procedures, it can serve as guidance for th design. An application example is presented of a containership subjected to a wav trace that includes an episodic wave that was measured during a severe storm in Central North Sea. The measured wave time history is modified in order to investigate the influence of the wave steepness on the induced vertical motions and loads. Th loads induced by the abnormal wave are compared for the first time with extreme values from long-term distributions.

Study on a Large-Span Steel Truss Roof Isolation Bearings for Wind Load Effect Isolation Effect

2013 ◽  
Vol 405-408 ◽  
pp. 1022-1027
Author(s):  
Zi Fen Fang ◽  
Zhi Qiang Zhang ◽  
Fei Liu
Keyword(s):  
Financial Services ◽  
Base Isolation ◽  
Wind Load ◽  
Isolation Effect ◽  
Load Effect ◽  
Large Span ◽  
Roof Structure ◽  
Rubber Bearing ◽  
Steel Truss ◽  
Load Effects

The isolation of large-span Steel Truss Roof structure is developed on the basis of base isolation. The isolation of large-span Steel Truss Roof structure is to limit the transmission of wind load effect to the substructure. Based on the engineering background, we mainly discuss using rubber bearing isolation structure wind load effects. This paper will explains and demonstrates the isolation mechanism of Large-span Steel Truss Structure,and than test and verify isolation effect by Calculating through the analysis of wind tunnel tests conducted on the Yancheng financial services center, which the steel truss roof isolation bearings for wind load effect isolation effect.

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