Improvement of extrapolation of traffic load effect on highway bridges based on Rice’s theory

Bridges are designed to withstand different types of loads, including dead, live, environmental, and occasional loads during their service period. Moving vehicles are the main source of the applied live load on bridges. The applied load to highway bridges depends on several traffic parameters such as weight of vehicles, axle load, configuration of axles, position of vehicles on the bridge, number of vehicles, direction, and vehicle’s speed. The estimation of traffic loadings on bridges are generally notional and, consequently, can be excessively conservative. Hence, accurate prediction of the in-service performance of a bridge structure is very desirable and great savings can be achieved through the accurate assessment of the applied traffic load in existing bridges. In this paper, a review is conducted on conventional vehicle-based health monitoring methods used for bridges. Vision-based, weigh in motion (WIM), bridge weigh in motion (BWIM), drive-by and vehicle bridge interaction (VBI)-based models are the methods that are generally used in the structural health monitoring (SHM) of bridges. The performance of vehicle-assisted methods is studied and suggestions for future work in this area are addressed, including alleviating the downsides of each approach to disentangle the complexities, and adopting intelligent and autonomous vehicle-assisted methods for health monitoring of bridges.

Download Full-text

Dynamic Reliability of Continuous Rigid-Frame Bridges under Stochastic Moving Vehicle Loads

Shock and Vibration ◽

10.1155/2020/8811105 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Naiwei Lu ◽

Kai Wang ◽

Honghao Wang ◽

Yang Liu ◽

Yuan Luo ◽

...

Keyword(s):

Reliability Index ◽

Volume Growth ◽

Traffic Monitoring ◽

Traffic Load ◽

Highway Traffic ◽

First Passage ◽

Growth Ratio ◽

Load Effect ◽

Dynamic Reliability ◽

Rigid Frame

The current volume of freight traffic has increased significantly during the past decades, impacted by the fast development of the national transportation market. As a result, the phenomena of truck overloading and traffic congestion emerge, which have resulted in numerous bridge collapse events or damage due to truck overloading. Thus, it is an urgent task to evaluate bridge safety under actual traffic loads. This study evaluated probabilistic dynamic load effects on rigid-frame bridges under highway traffic monitoring loads. The site-specific traffic monitoring data of a highway in China were utilized to establish stochastic traffic models. The dynamic effect was considered in a vehicle-bridge coupled vibration model, and the probability estimation was conducted based on the first-passage criterion of the girder deflection. The prototype bridge is a continuous rigid-frame bridge with a midspan length of 200 m and a pier height of 182 m. It is demonstrated that the dynamic traffic load effect follows Gaussian distribution, which can be treated as a stationary random process. The mean value and standard deviation of the deflections are 0.071 m and 0.088 m, respectively. The dynamic reliability index for the first passage of girder deflection is 6.45 for the current traffic condition. However, the reliability index decreases to 5.60 in the bridge lifetime, accounting for an average traffic volume growth ratio of 3.6%.

Download Full-text

Numerical and Experimental Assessment of the Highway Arch Viaduct

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.769.252 ◽

2015 ◽

Vol 769 ◽

pp. 252-259

Author(s):

Jan Bencat ◽

Maria Stehlikova ◽

Milan Skarupa

Keyword(s):

Dynamic Testing ◽

Highway Bridges ◽

Structural Condition ◽

Traffic Load ◽

Analytical Models ◽

Mode Shapes ◽

Bridge Structure ◽

Modal Damping ◽

Bridge Structures ◽

And Performance

Full–scale dynamic testing of bridge structures can provide valuable information on the service behavior and performance of structures. With the growing interest in the structural condition of highway bridges, dynamic testing can be used as a tool for assessing the integrity of bridges. From the measured dynamic response, induced by instructed passing trucks, modal parameters (natural frequencies, mode shapes and modal damping values) and system parameters (stiffness, mass and damping matrices) are obtained. These identified parameters can then be used to characterize and monitor the service of the bridge structure in the future. Analytical models of the structure can also be validated using these parameters [1,2]. The paper presents a procedure for estimating the traffic load bearing capacity of the steel arch highway viaduct Bridge Structure 205 (DC1–9, 755 m) constructed on Highway D1 in Nord Slovakia (Fig. 1) over the natural hollow basin via dynamic tests of the viaduct structures.

Download Full-text

Development of heavy truck models and their effects on girder bridges

Journal of Engineering Research ◽

10.36909/jer.8384 ◽

2021 ◽

Author(s):

Lang Liu ◽

◽

Lexian Zhang ◽

Jie Wang ◽

Hong Yang ◽

...

Keyword(s):

Bending Moment ◽

Highway Bridges ◽

Load Effect ◽

Girder Bridges ◽

Heavy Trucks ◽

Bridge Model ◽

Potential Factor ◽

Heavy Truck ◽

Beam Bridge ◽

T Beam

The traffic on highway bridges has been increasing in both volume and magnitude, which even has become one of the main reasons leading to damages and collapse of bridges. Most of the existing regulations for overloading checking are carried out based on various limits of gross vehicle weights and axle loads. However, the results of relevant researches show that weight is only a potential factor but not the dominating factor in threatening the safety of bridges. In this study, the concept of load-effect-based heavy truck is proposed for overloading checking, and then three years of WIM data were collected and used to develop heavy truck models for each truck type, based on the understanding of the characteristics and configurations of heavy trucks as well as the distribution of their main parameters. Furthermore, the typical heavy truck models selected and their possible combinations are applied to a simply supported pre-stressed concrete T-beam bridge model with three loading levels, considering one-lane, two-lane and three-lane loaded respectively, then the induced load effect, deflection and stress are discussed for 20 loading cases. The results show the bending moment caused by heavy trucks moving on multiple lanes is 1.6 times the value of the standard truck model in Chinese specification, and the eccentric loading due to a very heavy vehicle moving on single lane usually lead to more severe effect.

Download Full-text

A comparative study of bridge traffic load effect using micro-simulation and Eurocode load models

Bridge Maintenance, Safety, Management, Resilience and Sustainability - Bridge Maintenance, Safety and Management ◽

10.1201/b12352-514 ◽

2012 ◽

pp. 3420-3427 ◽

Cited By ~ 3

Author(s):

A Lipari ◽

E Obrien ◽

C Caprani

Keyword(s):

Comparative Study ◽

Traffic Load ◽

Load Effect ◽

Load Models ◽

Micro Simulation

Download Full-text

A Study on Assessment Method of Traffic Load Effect of Bridge in Service

10.1063/1.3452078 ◽

2010 ◽

Author(s):

Pan Ling ◽

Han Dajian ◽

Jane W. Z. Lu ◽

Andrew Y. T. Leung ◽

Vai Pan Iu ◽

...

Keyword(s):

Assessment Method ◽

Traffic Load ◽

Load Effect

Download Full-text

A DEVELOPMENT OF OPTICAL NETWORK UNIT POWER CONSUMPTION MODEL CONSIDERING TRAFFIC LOAD EFFECT

Jurnal Teknologi ◽

10.11113/jt.v80.10247 ◽

2018 ◽

Vol 80 (4) ◽

Cited By ~ 1

Author(s):

Arnidza Ramli ◽

Nadiatulhuda Zulkifli ◽

Auwalu Usman ◽

Sevia Mahdaliza Idrus

Keyword(s):

Energy Consumption ◽

Power Consumption ◽

Optical Network ◽

Sampling Rate ◽

Access Network ◽

Passive Optical Network ◽

Traffic Load ◽

Optical Network Unit ◽

Load Effect ◽

Consumption Model

Accurate and precise measurement of energy consumption for the deployment of fiber-to-the-home (FTTH) network using Gigabit passive optical network (GPON) is vital to the research community to develop models for the synthesis of energy-efficient protocols and algorithms for the access network. However, lack of power consumption measurement of optical network devices in the past has led to unrealistic and/or oversimplified model being used in simulations. Usually the access network devices are assumed always on and their consumption is both traffic and time independent. Therefore, in this paper we propose an experimentally-driven approach to i) characterize the Optical Network Unit (ONU) from the power consumption standpoint and ii) develop more accurate power consumption model for the ONU. We focus on ONU since it represents the main contributor to the energy consumption of optical access network. The real data in terms of the power consumption and traffic load have been obtained from continuous measurements performed on a GPON network testbed. The measurement is limited to a maximum 100 Mbps data rate due to a limitation in the sampling rate and precision of the measurement device. However, validation has been done with theoretical power consumption model in order to prove the feasibility of the proposed model. Our measurements show that the power consumption of the ONU exhibits a linear dependence on the traffic in which the power consumption at idle mode is 11.51 W while in low power mode the power consumption is around 7.52 W.

Download Full-text