Seismic Assessment of Reinforced Concrete Skewed Bridges under Near-Fault Ground Motions with Considering Soil-Structure Interaction- Case Study of Jack Tone Road On-Ramp Overcrossing Located in California

Document Type : Research Article


Department of Civil Engineering, Science and Research Branch, Islamic Azad University, Tehran, Iran


Seismic behavior of skewed bridges, the backbone of modern transportation networks, has not been well studied compared to their ordinary straight counterparts. Investigating past earthquakes, it can be evident that such bridges have experienced intensive damages specially due to girder unseating under the torsional effects of seismic responses coupling in longitudinal and transverse directions, which will be aggravated by local crushing of deck concrete due to pounding between the abutments and adjacent spans. Additionally, bridges are usually supported on Cast-In-Drilled-Hole extended pile-shafts. The inelastic behavior of the superstructure during an earthquake is profoundly dependant on soil strength due to the effect of surrounding soil properties on substructure stiffness. So, the main purpose of the present research is to evaluate the seismic responses of R.C skewed overcrossing to variations in some structural parameters by applying analytical models capturing backfill-abutment and soil-pile nonlinearities under near-fault ground motions with high-velocity pulses, especially in their strike-normal component, comparing the results with fixed-base model and finally obtain the most efficient ground motion intensity measure. A set of nonlinear time history analyses was conducted using seven pulse-like ground motions containing horizontal and vertical components on a two-span skewed bridge. Then, the effects of abutment skew angle, base condition modeling approach and soil strength on the revision of various demands were assessed and compared for both flexible- and rigid-base conditions. Furthermore, various analyses were carried out with respect to possible changes in soil properties ranging from soft to stiff for clayey and loose to dense for sandy soils besides the skew angle variations. It was observed that most of the demands, despite the changes in soil strength, were sensitive to an increase in abutment skew angle as a factor of structural stiffness and will often increase incrementally with that, but deck rotation was significantly affected by these variations. Considering foundation flexibility by a set of nonlinear springs can refine structural responses in most cases, particularly by applying Direct Method, based on precise modeling of structural components besides a vast region of encompassed soil around, which will impose an improving effect on various demands relative to the fixed-base condition.


Main Subjects

[1]  CALTRANS, 2013. Caltrans Seismic Design Criteria Version 1.7. California Department of Transportation, Sacramento, CA.
[2] Ghobarah A. A., Tso W. K., 1973. “Seismic Analysis of Skewed Highway Bridges with Intermediate Supports”. Earthquake Engineering & Structural Dynamics, 2(3), pp. 235-248.3.
[3] Bakht B., 1988. “Analysis of Some Skew Bridges as Right Bridges”. Journal of Structural Engineering, 114(10), pp. 2307-2322.
[4] Wakefield R. R., Nazmy A. S., Billington D. P., 1991. “Analysis of Seismic Failure in Skew RC Bridge”. Journal of Structural Engineering, 117(3), pp. 972-986.
[5] Meng J. Y., Lui E. M., 2000. “Seismic Analysis and Assessment of a Skew Highway Bridge”. Engineering Structures, 22(11), pp. 1433-1452.
[6] Maleki S., 2005. “Seismic Modeling of Skewed Bridges with Elastomeric Bearings and Side Retainers”. Journal of  Bridge Engineering, 10(4), pp. 442-449.
[7] Menassa C., Mabsout M., Tarhini K., Frederick G., 2007. “Influence of Skew Angle on Reinforced Concrete Slab Bridges”. Bridge Engineering, ASCE, 12(2), pp. 205-214.
[8] Shamsabadi A., Nordal S., 2006. “Modeling Passive Earth Pressures on Bridge Abutments for Nonlinear Seismic Soil-Structure Interaction using Plaxis”. Plaxis Bulletin, 20, pp. 8-15.
[9] Shamsabadi A., Rollins K. M., Kapuskar M., 2007. “Nonlinear Soil–Abutment–Bridge Structure Interaction for Seismic Performance-Based Design”. Geotechnical and Geoenvironmental Engineering, ASCE, 133(6), pp. 707-720.
[10] Huo X. S., Zhang Q., 2008. “Effect of Skewness on the Distribution of Live Load Reaction at Piers of Skewed Continuous Bridges”. Bridge Engineering, ASCE, 13(1), pp. 110-114.
[11] Kalantari A., Amjadian M., 2010. “An Approximate Method for Dynamic Analysis of Skewed Highway Bridges with Continuous Rigid Deck”. Engineering Structures, 32(9), pp. 2850-2860.
[12] Dimitrakopoulos E. G., 2011. “Seismic Response Analysis of Skew Bridges with Pounding Deck-Abutment Joints”. Engineering Structures, 33(3), pp. 813-826.
[13] Apirakvorapinit P., Mohammadi J., Shen J., 2012. “Analytical Investigation of Potential Seismic Damage to a Skewed Bridge”. Practice Periodical on Structural Design and Construction, 17(1), pp. 5-12.
[14] Zakeri B., Padgett J. E., Amiri G. G., 2014. “Fragility Analysis of Skewed Single-Frame Concrete Box-Girder Bridges”. Journal of Performance of Constructed Facilities, 28(3), pp. 571-582.
[15] Deepu S., Prajapat K., Ray-Chaudhuri S., 2014. “Seismic Vulnerability of Skew Bridges under Bi-directional Ground Motions”. Engineering Structures, 71, pp. 150-160.
[16] Kaviani P., Zareian F., Taciroglu E., 2014. Performance-Based Seismic Assessment of Skewed Bridges. PEER Report No. 2014/01. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA.
[17] Mallick M., Raychowdhury P., 2015. “Seismic Analysis of Highway Skew Bridges with Nonlinear Soil–Pile Interaction”. Transportation Geotechnics, 3, pp. 36-47.
[18] Ghotbi A. R., 2016. “Response Sensitivity Analyses of Skewed Bridges with and without Considering Soil–Structure Interaction”. Structures, 5, pp. 219-232.
[19] Omrani R., Mobasher B., Sheikhakbari Sh., Zareian F., Taciroglu E., 2017. “Variability in the Predicted Seismic Performance of a Typical Seat-type California Bridge due to Epistemic Uncertainties in its Abutment Backfill and Shear-key Models”. Engineering structures, 148, pp. 718-738. 
[20] McKenna F., Fenves G.L., Scott M.H., 2000. The Open System for Earthquake Engineering Simulation, University of California, Berkeley, CA. See also URL
[21] CSI, 2019. SAP2000- Linear and Nnonlinear Static and Dynamic Analysis and Design of Three-Dimensional Structures: Basic Analysis Reference Manual. Computers and Structures, Inc., Berkeley, CA.
[22] Aviram A., Mackie K. R., Stojadinovic B., 2008. Guidelines for Nonlinear Analysis of Bridge Structures in California. PEER Report No. 2008/03. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA.
[23] Mander J.B., Priestley M.J.N., Park R., 1988. “Theoretical Stress-Strain Model for Confined Concrete”. Journal of Structural Engineering, ASCE, 114(8), pp. 1804–1825.
[24] Bozorgzadeh A., Megally S., Restrepo J. I., Ashford S. A., 2006. Capacity Evaluation of Exterior Sacrificial Shear Keys of Bridge Abutments”. Journal of Bridge Engineering, ASCE, 11(5), pp. 555-565.
[25] Zhang J., Makris N., 2002. “Kinematic Response Functions and Dynamic Stiffness of Bridge Embankments”. Earthquake Engineering and Structural Dynamics, 31(11), pp.1933-1966.
[26] Matlock H., 1970. Correlation for Design of Laterally Loaded Piles in Soft Clay. In Proceedings of the 2nd Annual Offshore Technology Conference, Houston, Texas, OTC 1204.
[27] API, 2000. API Recommended Practice for Planning, Designing, and Constructing Fixed Offshore Platforms. Report No. RP 2A-WSD. American Petroleum Institute, Washington, D.C.
[28] Mackie K.R., Lu J., Elgamal A., 2012. "Performance-Based Earthquake Assessment of Bridge Systems Including Ground-foundation Interaction". Soil Dynamics and Earthquake Engineering, 42, pp. 184-196.
[29] Code No. 463, 2008. Road and Railway Bridges Seismic Resistant Design Code. Ministry of Roads and Transportation, Tehran, Iran, (in Persian).
[30] Charney F., 2010. “Site Classification Procedure for Seismic Design”. Seismic Loads, ASCE, 7(20), pp. 11-18.
[31] ATC, 1996. Improved Seismic Design Criteria for California Bridges: Provisional Recommendations, ATC Report No. ATC-32. Applied Technology Council, Redwood City, CA.
[32] PEER Ground Motion Database, Pacific Earthquake Engineering Research Center. See also URL
[33]  H. Soltani, F. Emami, 2019. Seismic Behavior of Reinforced Concrete Skew Bridges Embedded on Stiff Clay under Near Fault Ground Motions, with Considering Soil-Structure Interaction. Proceedings of the 3rd International Conference on Applied Researches in Structural Engineering and Construction Management, Tehran, Iran (in Persian).
[34] ASCE, 2010. Minimum Design Loads for Buildings and Other Structures, ASCE 7-10. American Society of Civil Engineers, Reston, VA.