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

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.

2011 ◽  
Vol 255-260 ◽  
pp. 338-344 ◽  
Author(s):  
Ying Wang ◽  
Feng Lin ◽  
Xiang Lin Gu

Due to the absence of provision for the load and resistance factors in design codes in China, designers often quote the provisions which are given in criterion or guidance of other countries such as USA. However, the partial safety factors of the load are various in different criterions. Based on the reliability theory, the load and resistance factors for progressive collapse resistance design of building structures were determined in this study. Firstly the simplified format of design expression in the ultimate state was obtained according to the expression in routine structural design. Then the failure probability of a structure during design reference period was taken as the sum of the probability of all incompatible failure events in this period, and the objective reliability index of the structure could be obtained. Finally using trial-and-error procedure and JC method, reliability analysis was performed for structural members to obtain the partial safety factors of load effects and resistance and the coefficient for combination value of load effects in design expression in the ultimate state. In this paper the load and resistance factors for progressive collapse resistance design of reinforced concrete structures subjected to blast was calculated as an example, and the recommendation values were given for the application at last.


2013 ◽  
Vol 671-674 ◽  
pp. 1362-1366
Author(s):  
Peng He ◽  
Sheng Jin Ge ◽  
Min Gang Zhai

Monte-Carlo was applied to generate random traffic flow after frequent, moderate and rare earthquake respectively based on sample of vehicle investigation in“907”Zhaotong, Yiliang earthquake (2012), Yunnan province, considering vehicle parameters, such as types, driving, distance, ratio in earthquake-relief campaign. Vehicle load effect was analyzed for different spans of Simply Supported Beam Bridge, then characteristic value of lane loading which ruled by 《General Code Designs of Highway Bridges and Culverts(JTG D60-04)》(China) was revised. Research can not only provide standard for rapid estimate and repair of bridge after earthquake, but also give theoretical basis for revising anti-seismic codes or guidelines in China.


Author(s):  
Federico Barranco Cicilia ◽  
Edison Castro Prates de Lima ◽  
Lui´s Volnei Sudati Sagrilo

This paper presents a Load and Resistance Factor Design (LRFD) criterion applied to the design of Tension Leg Platform (TLP) tendons in their intact condition. The design criterion considers the Ultimate Limit State (ULS) of any tendon section along its whole length taking into account both dynamic interactions of load effects and the statistics of its associated extreme response. The partial safety factors are calibrated through a long-term reliability-based methodology for the storm environmental conditions, like hurricanes and winter storms, in deep waters of the Campeche Bay, Mexico. In the reliability analysis, the uncertainties in the definition of load effects and analytic limit state models for calculation of tendon strength and randomness of material properties are included. The results show that the partial safety factors reflect both uncertainty content and the importance of the random variables in structural reliability analysis. When tendons are designed according to the developed LRFD criterion, a less scattered variation of reliability indexes is obtained for different tendon sections across a single or various TLP designs.


2020 ◽  
Vol 47 (1) ◽  
pp. 88-95
Author(s):  
B. Algohi ◽  
B. Bakht ◽  
H. Khalid ◽  
A. Mufti ◽  
J. Regehr

Three highway bridges in the Canadian province of Manitoba are being monitored continuously not only for their long-term performance but also for bridge weighing-in-motion (BWIM). Data collected for the BWIM study has led to some observations that have far-reaching consequences about the design and evaluation loads for highway bridges. This paper presents the well-known concept of equivalent base length, Bm, as a useful tool for comparing trucks with different axle weight and spacing configurations as they influence load effects in all bridges. It is discussed that the statistics of gross vehicle weights (GVWs), W, collected over a one-month period is not significantly different from that for the GVW data collected over a longer period. A rational method concludes that the value of W for the CL-W Truck, the design live load specified by the Canadian Highway Bridge Design Code, is 555 kN for Manitoba. The observed truck data in Manitoba presented on the W–Bm space is found to be similar to that collected in the Canadian province of Ontario more than four decades ago. It was also found that the multi-presence factors, accounting for the presence of side-by-side trucks in two-lane bridges, specified in North American bridge design and evaluation codes are somewhat conservative.


2016 ◽  
Vol 11 (3) ◽  
pp. 197-204
Author(s):  
Zigang Xu ◽  
Qiang Han ◽  
Junfeng Jia ◽  
Zilan Zhong ◽  
Chao Huang

In order to assess the vehicle load carrying capacity of existing bridges on the national highway G103 in Beijing, the vehicle load model for the practical traffic flow conditions needs to be determined. Based on the traffic axle load data measured by the weigh-in-motion system and the methods proposed by General Code for Design of Highway Bridges and Culverts (JTG D60-2004) and Code for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts (JTG D62-2004), the vehicle load parameters under practical traffic flow conditions are investigated. A typical 6-axle vehicle model with a 2-1-3 axial pattern is proposed by using the statistical analysis of total weight, axial weight, etc. The live load effects of Daliushu No. 2 Bridge, one highway bridge on the national highway G103, are analyzed using the proposed model and compared to the vehicle load model given in the Chinese code. The results show that there are great differences in the vehicle load parameters and the live load effects from the proposed vehicle load model increased by 20–50% compared with the model given by the code. The overweight vehicles are potential threats to the safety of existing bridges.


2012 ◽  
Vol 5 ◽  
pp. 157-161 ◽  
Author(s):  
Zi Jian Wang ◽  
Rong Pan Hu ◽  
Shun Long Li

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.


2015 ◽  
Vol 2481 (1) ◽  
pp. 132-139 ◽  
Author(s):  
Jun Wu ◽  
Fei Yang ◽  
Wanshui Han ◽  
Liujie Wu ◽  
Qiang Xiao ◽  
...  

2021 ◽  
Vol 6 (2) ◽  
pp. 75
Author(s):  
Muhammad Dzulkifly ◽  
Raffy Frandito ◽  
Mochammad Rafli Ramadhani ◽  
Wildan Rahmawan ◽  
Farid Triawan

<p>Almost every year, floods disaster becomes the scourge of many countries in the world, including Indonesia.  When the flood comes and submerges the houses, every item and household furniture in it will also be submerged in flood water. Furniture that is heavy and difficult to move, especially electronic equipment such as refrigerators, may be left by the owner when a flood occurs. To prevent the furniture from submerging, a lifting kit is needed. For this reason, the purpose of this work is to design a mechanical tool/kit that can lift or elevate the electronic furniture such as refrigerator to a higher position and avoid the damage caused by flood. The kit is expected to be able to cover a 100 x 80 cm base of the refrigerator with maximum load of 200 kg. The elevation of the lifting kit is set to be higher than 50 cm. Calculation for the stress and fatigue analysis is also performed to determine the strength of the structure. As a result, the obtained safety factors for the critical components under static and fatigue loading conditions show values of more than one, indicating the product is safe for real operation. In addition, the required torque to produce the elevation is also calculated and discussed.</p>


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