Comparison of seismic fragility of special moment frames in recent editions of ASCE 7 and ACI 318 regulations

Document Type : Research

Authors

1 Associate Professor, Department of Civil Engineering, Isfahan University of Technology, Isfahan, Iran.

2 Senior structural engineer, Isfahan, Iran.

Abstract

The seismic safety levels provided by the three most recent editions of ACI and ASCE regulations for new moment frame structures are determined. Five special RC moment frames having 3, 5, 10, 15, and 20 stories are designed separately based on ACI 318-99, ACI 318-05, and ACI 318-11, and the associated seismic regulations of UBC 97, ASCE 7-05, and ASCE 7-10. A suit of 10 consistent earthquake records is selected for non-linear dynamic analysis of buildings. Incremental dynamic analysis is conducted, and the corresponding fragility curves are calculated. The comparison of results shows that seismic safety of special moment frame buildings has considerably improved from ACI 318-99 to ACI 318-11, and from UBC 97 to ASCE 7-10, owing its larger part to the improvements made in the two latter versions of the mentioned building codes. However, the safety enhancement is not uniform and is much less for buildings with larger fundamental periods, especially for periods larger than 1.0 sec. For structures with fundamental periods smaller than 1 sec, the collapse ratio has increased up to more than 70%. For larger fundamental periods, the increase is less than 20%. Changes in ASCE7 with regard to the R-factor and coefficients of the load combination equations and its introduction of stricter requirements for the allowable story drift are pinpointed to be the most important factors. For the ACI codes, stricter requirements regarding the confinement of the plastic hinges and configuration of the longitudinal reinforcement are recognized to be the most influential changes.

Keywords


1. American Concrete Institute and International Organization for Standardization. (1999). Building Code Requirements for Structural Concrete (ACI 318-99).
2. American Concrete Institute and International Organization for Standardization. (2005). Building Code Requirements for Structural Concrete (ACI 318-05).
3. American Concrete Institute and International Organization for Standardization (2011). Building Code Requirements for Structural Concrete (ACI 318-11).
4. Uniform Building Code (UBC-97). (1997, April). Structural Engineering Design Provisions. International Conference of Building Officials, California, USA.
5. American Society of Civil Engineers. (2005). Minimum Design Loads for Buildings And Other Structures (ASCE 7-05).
6. American Society of Civil Engineers (2010). Minimum Design Loads for Buildings And Other Structures (ASCE 7-10).
7. Applied Technology Council. (2009). Quantification of Building Seismic Performance Factors (FEMA P695).
8. Richard, M. J., Albano, L. D., Kelly, D., & Liel, A. B. (2010). Case Study On The Seismic Performance of Reinforced Concrete Intermediate Moment Frames Using ACI Design Provisions. In Structures Congress 2010. [DOI:10.1061/41130(369)318]
9. Yi, W.J., He, Q.F., Xiao, Y., & Kunnath, S.K. (2008). Experimental Study on Progressive Collapse-Resistant Behavior of Reinforced Concrete Frame Structures. ACI Structural Journal, 105(4), 433-439. [DOI:10.14359/19857]
10. Ibarra, L.F., & Krawinkler, H. (2005). Global Collapse of Frame Structures under Seismic Excitations. Ph.D. Dissertation. Stanford University.
11. Haselton, C.B., & Deierlein, G.G. (2007). Assessing Seismic Collapse Safety of Modern Reinforced Concrete Moment Frame Buildings. Ph.D. Dissertation. Department of Civil and Environmental Engineering, Stanford University. [DOI:10.1061/40944(249)22]
12. Zareian, F., Lignos, D. G., & Krawinkler, H. (2010). Evaluation of Seismic Collapse Performance of Steel Special Moment Resisting Frames Using FEMA P695 (ATC-63) Methodology. In Structures Congress 2010, (1275-1286). [DOI:10.1061/41130(369)116]
13. El Howary, H. A., & Mehanny, S. S. F. (2011). Seismic Vulnerability Evaluation of RC Moment Frame Buildings in Moderate Seismic Zones. Earthquake Engineering & Structural Dynamics, 40(2), 215-235. [DOI:10.1002/eqe.1016]
14. Masi, A., Digrisolo, A., & Manfredi, V. (2015). Fragility Curves of Gravity-Load Designed RC Buildings with Regularity in Plan. Earthquakes and Structures, 9(1), 1-27. [DOI:10.12989/eas.2015.9.1.001]
15. Soltangharaei, V., Razi, M., & Vahdani, R. (2016). Seismic Fragility of Lateral Force Resisting Systems Under Near and Far-Fault Ground Motions. International Journal of Structural Engineering, 7(3), 291-303. [DOI:10.1504/IJSTRUCTE.2016.077722]
16. Li, G., Dong, Z. Q., Li, H. N., & Yang, Y. B. (2017). Seismic Collapse Analysis of Concentrically-Braced Frames by the IDA Method. Advanced Steel Construction, 13(3), 273-292.
17. Surana, M., Singh, Y., & Lang, D. H. (2018). Effect of Strong-Column Weak-Beam Design Provision on the Seismic Fragility of RC Frame Buildings. International Journal of Advanced Structural Engineering, 10(2), 131-141. [DOI:10.1007/s40091-018-0187-z]
18. Speicher, M.S., Dukes, J., & Wong, K.K. (2018, June). Using FEMA P695 to Interpret ASCE 41 Seismic Performance of Special Moment Frames. Eleventh U.S. National Conference on Earthquake Engineering, Los Angeles, USA.
19. Farahbakhshtooli, A., & Bhowmick, A.K. (2019). Seismic Collapse Assessment of Stiffened Steel Plate Shear Walls Using FEMA P695 Methodology. Engineering Structures, 200, Article 109714. [DOI:10.1016/j.engstruct.2019.109714]
20. Kalantari, A., & Roohbakhsh, H. (2019). Expected Seismic Fragility of Code-Conforming RC Moment Resisting Frames Under Twin Seismic Events. Journal of Building Engineering, Article 101098. [DOI:10.1016/j.jobe.2019.101098]
21. Kassem, M. M., Mohamed Nazri, F., Wei, L. J., Tan, C. G., Shahidan, S., & Mohd Zuki, S. S. (2019). Seismic Fragility Assessment for Moment-Resisting Concrete Frame with Setback Under Repeated Earthquakes. Asian Journal of Civil Engineering, 20(3), 465-477. [DOI:10.1007/s42107-019-00119-z]
22. Di Trapani, F., & Malavisi, M. (2019). Seismic Fragility Assessment of Infilled Frames Subject to Mainshock/Aftershock Sequences Using a Double Incremental Dynamic Analysis Approach. Bulletin of Earthquake Engineering, 17(1), 211-235. [DOI:10.1007/s10518-018-0445-2]
23. Fattahi, F., & Gholizadeh, S. (2019). Seismic Fragility Assessment of Optimally Designed Steel Moment Frames. Engineering Structures, 179, 37-51. [DOI:10.1016/j.engstruct.2018.10.075]
24. Sotoudeh, M. A., Ghaemian, M., & Moghadam, A. S. (2019). Determination of Limit-States for Near-Fault Seismic Fragility Assessment of Concrete Gravity Dams. Scientia Iranica. Transaction A, Civil Engineering, 26(3), 1135-1155.
25. Bakhshi, A., & Soltanieh, H. (2019). Development of Fragility Curves for Existing Residential Steel Buildings with Concentrically Braced Frames. Scientia Iranica, 26(4), 2212-2228.
26. Jin, S., & Gong, J. (2020). Damage Performance Based Seismic Capacity and Fragility Analysis of Existing Concrete Containment Structure Subjected to Near Fault Ground motions. Nuclear Engineering and Design, 360, Article110478. [DOI:10.1016/j.nucengdes.2019.110478]
27. Hashmi, A. K., & Madan, A. (2020). Fragility Analysis of Infilled Reinforced Concrete Frames Subjected to Near-Field Ground Motions. KSCE Journal of Civil Engineering, 24(1), 122-130. [DOI:10.1007/s12205-020-1443-x]
28. SeismoSoft. (2015). Earthquake Engineering Software Solutions. Pavia, Italy.
29. Pacific Earthquake Engineering Research Center (PEER). (2015). Open System for Earthquake Engineering simulation.
30. Zhang, G. (2006). Inelastic Modeling of Reinforcing Bars and Blind Analysis of The Benchmark Tests on Beam Column Joints Under Cyclic Loading. Master's Thesis. Rose School, European School for Advanced Studies in Reduction of Seismic Risk.
31. Mander, J. B., Priestley, M. J., & Park, R. (1988). Theoretical Stress-Strain Model for Confined Concrete. Journal of Structural Engineering, 114(8), 1804-1826. [DOI:10.1061/(ASCE)0733-9445(1988)114:8(1804)]
32. Ho, J. C. M., Pam, H. J., Peng, J., & Wong, Y. L. (2011). Maximum Concrete Stress Developed in Unconfined Flexural RC Members. Computers and Concrete, 8(2), 207-227. [DOI:10.12989/cac.2011.8.2.207]
33. Ergun, M., & Ates, S. (2013). Selecting and Scaling Ground Motion Time Histories According to Eurocode 8 and ASCE 7-05. Earthquakes and Structures, 5(2), 129-142. [DOI:10.12989/eas.2013.5.2.129]
34. Zuboski, G.R. (2013). Stress-Strain Behavior for Actively Confined Concrete Using Shape Memory Alloy Wires. Thesis Presented in Partial Fulfillment of the Requirements for the Degree Master of Science .Graduate School of The Ohio State University.
35. Mazars, J., & Grange, S. (2015). Modeling of Reinforced Concrete Structural Members for Engineering Purposes. Computers and Concrete, 16(5), 683-701. [DOI:10.12989/cac.2015.16.5.683]
36. Panagiotakos, T. B., & Fardis, M. N. (2001). Deformations of Reinforced Concrete Members at Yielding and Ultimate. Structural Journal, 98(2), 135-148. [DOI:10.14359/10181]
37. Shome, N., Cornell, C. A., Bazzurro, P., & Carballo, J. E. (1998). Earthquakes, Records, and Nonlinear Responses. Earthquake Spectra, 14(3), 469-500. [DOI:10.1193/1.1586011]
38. PEER, Pacific Earthquake Engineering Research Center. (2015). http://peer.berkeley.edu/nga.
39. Vamvatsikos, D., & Cornell, C. A. (2002). Incremental Dynamic Analysis. Earthquake Engineering & Structural Dynamics, 31(3), 491-514. [DOI:10.1002/eqe.141]
40. Haselton, C. B., Liel, A. B., & Deierlein, G. G. (2009). Simulating structural collapse due to earthquakes: model idealization, model calibration, and numerical solution algorithms. Computational methods in structural dynamics and earthquake engineering (COMPDYN).