Characteristic dynamic traffic load effects in bridges

The traffic load has grown significantly in recent years, which might be a threat for the service safety of existing bridges. Thus, it is an urgent task to assess the actual traffic load effects on bridges, considering actual heavy traffic load instead of design traffic load. This study presents a framework for extrapolating maximum dynamic traffic load effects on large bridges using site-specific traffic monitoring data. The framework involves vehicle–bridge interaction analysis and probabilistic modelling of extreme values. The weigh-in-motion measurements of a busy highway in China were collected for stochastic traffic load modelling. Case studies of two long-span cable-supported bridge based on the weigh-in-motion measurements were conducted to demonstrate the effectiveness of the proposed framework. It is demonstrated that Rice’s level-crossing approach can capture both dynamic and probabilistic characteristics of the traffic load effects. The root-mean-square displacement of the cable-stayed bridge follows a C-type distribution, and the one for the suspension bridge follows an M-type distribution, which is associated with the first-order mode shapes of the two types of bridges. The amplification factors for the cable-stayed bridge and the suspension bridge are 5.9% and 3.6%, respectively. The numerical analysis indicates that the dynamic effect for extrapolation is weaker with the increase in bridge span length, but the effect of traffic volume growth will be more significant.

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Maximum Probabilistic and Dynamic Traffic Load Effects on Short-to-Medium Span Bridges

Computer Modeling in Engineering & Sciences ◽

10.32604/cmes.2021.013792 ◽

2021 ◽

Vol 127 (1) ◽

pp. 345-360

Author(s):

Naiwei Lu ◽

Honghao Wang ◽

Kai Wang ◽

Yang Liu

Keyword(s):

Traffic Load ◽

Dynamic Traffic ◽

Load Effects

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Influence on bridge reliability of uncertainty in estimated traffic load-effects

Safety, Reliability, Risk and Life-Cycle Performance of Structures and Infrastructures ◽

10.1201/b16387-550 ◽

2014 ◽

pp. 3787-3793 ◽

Cited By ~ 1

Author(s):

S Reid ◽

C Caprani

Keyword(s):

Traffic Load ◽

Load Effects ◽

Bridge Reliability

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Traffic load effects on dynamic bridge performance

Maintenance, Monitoring, Safety, Risk and Resilience of Bridges and Bridge Networks ◽

10.1201/9781315207681-365 ◽

2016 ◽

pp. 563-563

Author(s):

I. Paeglite ◽

J. Smirnovs ◽

A. Paeglitis

Keyword(s):

Traffic Load ◽

Load Effects ◽

Bridge Performance

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Evaluating Probabilistic Traffic Load Effects on Large Bridges Using Long-Term Traffic Monitoring Data

Sensors ◽

10.3390/s19225056 ◽

2019 ◽

Vol 19 (22) ◽

pp. 5056 ◽

Cited By ~ 7

Author(s):

Lu ◽

Ma ◽

Liu

Keyword(s):

Control Measure ◽

Heavy Traffic ◽

Suspension Bridge ◽

Traffic Monitoring ◽

Traffic Load ◽

Monitoring Data ◽

Traffic Density ◽

Maximum Deflection ◽

Load Effects ◽

Crossing Theory

With the steadily growing of global transportation market, the traffic load has increased dramatically over the past decades, which may develop into a risk source for existing bridges. The simultaneous presence of heavy trucks that are random in nature governs the serviceability limit for large bridges. This study investigated probabilistic traffic load effects on large bridges under actual heavy traffic load. Initially, critical stochastic traffic loading scenarios were simulated based on millions of traffic monitoring data in a highway bridge in China. A methodology of extrapolating maximum traffic load effects was presented based on the level-crossing theory. The effectiveness of the proposed method was demonstrated by probabilistic deflection investigation of a suspension bridge. Influence of traffic density variation and overloading control on the maximum deflection was investigated as recommendations for designers and managers. The numerical results show that the congested traffic mostly governs the critical traffic load effects on large bridges. Traffic growth results in higher maximum deformations and probabilities of failure of the bridge in its lifetime. Since the critical loading scenario contains multi-types of overloaded trucks, an effective overloading control measure has a remarkable influence on the lifetime maximum deflection. The stochastic traffic model and corresponding computational framework is expected to be developed to more types of bridges.

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Novel Multi-Level Dynamic Traffic Load-Balancing Protocol for Data Center

Symmetry ◽

10.3390/sym11020145 ◽

2019 ◽

Vol 11 (2) ◽

pp. 145 ◽

Cited By ~ 2

Author(s):

Sheeba Memon ◽

Jiawei Huang ◽

Hussain Saajid ◽

Naadiya Khuda Bux ◽

Arshad Saleem ◽

...

Keyword(s):

Load Balancing ◽

Data Center ◽

State Of The Art ◽

Traffic Load ◽

Parameter Setting ◽

Dynamic Traffic ◽

Typical Data ◽

Fixed Parameter ◽

Multi Level ◽

Traffic Load Balancing

Typically, the production data centers function with various risk factors, such as for instance the network dynamicity, topological asymmetry, and switch failures. Hence, the load-balancing schemes should consider the sensing accurate path circumstances as well as the reduction of failures. However, under dynamic traffic, current load-balancing schemes use the fixed parameter setting, resulting in suboptimal performances. Therefore, we propose a multi-level dynamic traffic load-balancing (MDTLB) protocol, which uses an adaptive approach of parameter setting. The simulation results show that the MDTLB outperforms the state-of-the-art schemes in terms of both the flow completion time and throughput in typical data center applications.

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