Title:
Live Load on Concrete Bridge Decks
Author(s):
Sylwia Stawska, Jacek Chmielewski, Andrzej S. Nowak
Publication:
Symposium Paper
Volume:
352
Issue:
Appears on pages(s):
116-134
Keywords:
bridge, decks, extrapolation, live load, statistical parameters, weigh-in-motion
DOI:
10.14359/51734860
Date:
5/31/2022
Abstract:
To ensure the safety of bridge decks under vehicular traffic, there is a need for calibration of live load factors that envelope transverse traffic-induced load spectra. The study objective is to develop statistical parameters of live load for bridge deck design. Development of live load model required WIM data processing, transverse live load effects calculations, extrapolations analysis, distribution fitting, and computation of statistical parameters: bias factor and coefficient of variation. Maximum expected values of live load depend on the considered time period and traffic volume. The procedure is demonstrated on California example for various bridge configurations, traffic volumes, and return periods. The calculated statistical parameters include bias factor, which is the ratio of mean-to-nominal, and the coefficient of variation, which is the ratio of standard deviation and the mean. Computed bias factors vary between 1.18-1.35, and the coefficient of variation is 11-12%. The results can serve as a basis for verification of the live load factors for concrete decks in a reliability-based calibration. To ensure the safety of bridge decks under vehicular traffic, there is a need for calibration of live load factors that envelope transverse traffic-induced load spectra.
Related References:
Anitori, G., Casas, J. R., and Ghosn, M. (2017). “WIM-Based Live-Load Model for Advanced Analysis of Simply Supported Short- and Medium-Span Highway Bridges.” Journal of Bridge Engineering, 22(10), 04017062.
Caprani, C. C., OBrien, E. J., and McLachlan, G. J. (2008a). “Characteristic traffic load effects from a mixture of loading events on short to medium span bridges.” Structural Safety, 30(5), 394–404.
Caprani, C. C., OBrien, E. J., and McLachlan, G. J. (2008b). “Characteristic traffic load effects from a mixture of loading events on short to medium span bridges.” Structural Safety, 30(5), 394–404.
Flint, A. R., and Jacob, B. (1996). “Extreme Traffic Loads on Road Bridges and Target Values of Their Effects for Code Calibration.” Proceedings of IABSE Colloquium, 469–78.
Hallenbeck, M. E., Weinblatt, H., and Program, N. C. H. R. (2004). Equipment for Collecting Traffic Load Data. Transportation Research Board.
Iatsko, O., Babu, A. R., Stallings, J. M., and Nowak, A. S. (2020). “Weigh-in-Motion-Based Fatigue Damage Assessment.” Transportation Research Record, SAGE Publications Inc, 0361198120919758.
Kulicki, J.M., Wasser, W.G., Mertz, D.R., and Nowak, A.S.,. (2015). Bridges for Service Life Beyond 100 Years: Service Limit State Design. Transportation Research Board, Washington D.C.
Leahy, C., OBrien, E. J., Enright, B., and Hajializadeh, D. (2015). “Review of HL-93 Bridge Traffic Load Model Using an Extensive WIM Database.” Journal of Bridge Engineering, 20(10), 04014115.
Leahy, OBrien, and O’Connor. (2016). “The effect of traffic growth on characteristic bridge load effects.” Transportation Research Procedia, Transportation Research Procedia 14 (2016) 3990-3999.
Li, W., and Nyholt, D. R. (2001). “Marker Selection by Akaike Information Criterion and Bayesian Information Criterion.” Genetic Epidemiology, 21(S1), S272–S277.
Moses, F. (2001). Calibration of load factors for LRFR bridge evaluation. NCHRP report, National Academy Press, Washington, D.C.
Nowak, A. S. (1999a). “Calibration of LRFD Bridge Design Code. NCHRP Report 368.” Transportation Research Board. National Research Council.
Nowak, A. S. (1999b). “Calibration of LRFD Bridge Design Code.” NCHRP Report, (368).
Nowak, A. S., and Rakoczy, P. (2013). “WIM-based Live load for Bridges.” KSCE Journal of Civil Engineering, 17(3):568-574.
OBrien, E. J., and Enright, B. (2013). “Using Weigh-in-Motion Data to Determine Aggressiveness of Traffic for Bridge Loading.” Journal of Bridge Engineering, 18(3), 232–239.
Ramachandran, A. N., Taylor, K. L., Stone, J. R., and Sajjadi, S. S. (2011). “NCDOT Quality Control Methods for Weigh-in-Motion Data.” Public Works Management & Policy, SAGE Publications Inc, 16(1), 3–19.
Ramesh Babu, A., Iatsko, O., and Nowak, A. S. (2019). “Comparison of Bridge Live Loads in US and Europe.” Structural Engineering International, 29(1), 84–93.
Siavashi, S., and Eamon, C. D. (2019). “Development of Traffic Live-Load Models for Bridge Superstructure Rating with RBDO and Best Selection Approach.” Journal of Bridge Engineering, 24(8), 04019084.
Sivakumar, B., Ghosn, M., and Moses, F. (2008). Protocols for Collecting and Using Traffic Data in Bridge Design. Transportation Research Board, Washington, D.C.
Stawska, S., Chmielewski, J., Bacharz, M., Bacharz, K., and Nowak, A. (2021). “Comparative Accuracy Analysis of Truck Weight Measurement Techniques.” Applied Sciences, Multidisciplinary Digital Publishing Institute, 11(2), 745.
Vandervalk-Ostrander, A. (2009). AASHTO guidelines for traffic data programs. American Association of State Highway and Transportation Officials., Washington, D.C.