Investigation of the Live-Load Effects on Long-Span Bridges under Traffic Flows
Publication: Journal of Bridge Engineering
Volume 23, Issue 5
Abstract
Different from short-span girder bridges, long-span bridges support a large amount of traffic, which significantly influences the dynamic performance of the bridge. The design live load on long-span bridges has seldom been investigated to take into account the dynamic effects from multiple vehicles in traffic flow. The current AASHTO LRFD specification was primarily developed for and calibrated from bridges with spans of 61.0 m (200 ft) or less. Therefore, it is unknown whether it is risky or conservative to use the same design live load from AASHTO on long-span bridges with spans longer than 100 m. Taking advantage of the advanced simulation methodology on the coupled bridge-traffic system developed recently, the live-load effects on a prototype long-span bridge from stochastic traffic flow were comprehensively studied, including the extreme dynamic response and the dynamic amplification factors for different bridge components. To evaluate the applicability of the design live-load in the current AASHTO specification on long-span bridges, the load effects on the prototype long-span bridge were numerically assessed and were compared with the corresponding response envelopes of the bridge under stochastic traffic flow. It was found that the design live load from AASHTO may be unsafe for use as the live load for the design of the bridge girder, pylon, and stay cables for long-span bridges.
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Acknowledgments
This research was supported by the National Science Foundation Grant CMMI-1335571 and the Center for Risk-Based Community Resilience Planning sponsored by National Institute of Standards and Technology, which are gratefully acknowledged. The writers take sole responsibility for the views expressed in the paper, which may not represent the opinions of the sponsors.
References
AASHTO. (1994). AASHTO LRFD bridge design specifications, 1st Ed., Washington, DC.
AASHTO. (2012). AASHTO LRFD bridge design specifications, 6th Ed., Washington, DC.
Aluri, S., Jinka, C., and GangaRao, H. V. S. (2005). “Dynamic response of three fiber reinforced polymer composite bridges.” J. Bridge Eng., 722–730.
ASCE Subcommittee on Performance of Bridges. (2003). Assessment of performance of vital long-span bridges in the United States, R. J. Kratky, ed., Reston, VA.
Bakht, B., and Pinjarkar, S. G. (1989). “Dynamic testing of highway bridges—A review.” Transp. Res. Rec., 1223, 93–100.
Buckland, P. G. (1981). “Recommended design loads for bridges.” J. Struct. Div., 107(7), 1161–1213.
Buckland, P. G. (1991). “North American and British long-span bridge loads.” J. Struct. Eng., 2972–2987.
Cai, C. S., and Chen, S. R. (2004). “Framework of vehicle-bridge-wind dynamic analysis.” J. Wind Eng. Ind. Aerodyn., 92(Jun), 579–607.
Caprani, C. C., González, A., Rattigan, P. H., and OBrien, E. J. (2012). “Assessment dynamic ratio for traffic loading on highway bridges.” Struct. Infrastruct. Eng., 8(3), 295–304.
Chen, S. R., and Wu, J. (2010). “Dynamic performance simulation of long-span bridge under combined loads of stochastic traffic and wind.” J. Bridge Eng., 219–230.
Chen, S. R., and Wu, J. (2011). “Modeling stochastic live load for long-span bridge based on microscopic traffic flow simulation.” Comput. Struct., 89(May), 813–824.
Deng, L., and Cai, C. S. (2010). “Development of dynamic impact factor for performance evaluation of existing multi-girder concrete bridges.” Eng. Struct., 32(1), 21–31.
Deng, L., Yu, Y., Zou, Q., and Cai, C. S. (2015). “State-of-the-art review of dynamic impact factors of highway bridges.” J. Bridge Eng., 04014080.
Guo, W. H., and Xu, Y. L. (2001). “Fully computerized approach to study cable-stayed bridge–vehicle interaction.” J. Sound Vib., 248(4), 745–761.
Lutomirska, M. (2009). “Live load model for long-span bridges.” Ph.D. thesis, Univ. of Nebraska–Lincoln, Lincoln, NE.
Nagel, K., and Schreckenberg, M. (1992). “A cellular automaton model for freeway traffic.” J. Phys. I, 2(12), 2221–2229.
OBrien, E. J., Rattigan, P., González, A., Dowling, J., and Žnidarič, C. A. (2009). “Characteristic dynamic traffic load effects in bridges.” Eng. Struct., 31(7), 1607–1612.
Pines, D., and Aktan, A. E. (2002). “Status of structural health monitoring of long-span bridges in the United States.” Prog. Struct. Eng. Mater., 4(4), 372–380.
Senthilvasan, J., Thambiratnam, D. P., and Brameld, G. H. (2002). “Dynamic response of a curved bridge under moving truck load.” Eng. Struct., 24(10), 1283–1293.
Xanthakos, P. P. (1994). Theory and design of bridges, Wiley-Interscience, Hoboken, NJ.
Zhou, Y., and Chen, S. (2015). “Dynamic simulation of long-span bridge-traffic system subjected to combined service and extreme loads.” J. Struct. Eng., 04014215.
Zhou, Y., and Chen, S. (2016a). “Framework of nonlinear dynamic simulation of long-span cable-stayed bridges subjected to cable-loss incidents.” J. Struct. Eng., 04015160.
Zhou, Y., and Chen, S. (2016b). “Vehicle ride comfort analysis with whole-body vibration on long-span bridges subjected to crosswind.” J. Wind Eng. Ind. Aerodyn., 155(Aug), 126–140.
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© 2018 American Society of Civil Engineers.
History
Received: Mar 6, 2017
Accepted: Oct 6, 2017
Published online: Mar 12, 2018
Published in print: May 1, 2018
Discussion open until: Aug 12, 2018
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