Comparison between standards for seismic design of liquid storage tanks with respect to soil-foundation-structure interaction and uplift
DOI:
https://doi.org/10.5459/bnzsee.45.1.40-46Abstract
Field evidence has established that strong earthquakes can cause severe damage or even collapse of liquid storage tanks. Many tanks worldwide are built near the coast on soft soils of marginal quality. Because of the difference in stiffness between the tank (rigid), foundation (rigid) and the soil (flexible), soil-foundation-structure interaction (SFSI) has an important effect on the seismic response, often causing an elongation of the period of the impulsive mode. This elongation is likely to produce a significant change in the seismic response of the tank and will affect the loading on the structure. An issue not well understood, in the case of unanchored tanks, is uplift of the tank base that usually occurs under anything more than moderate dynamic loading. This paper presents a comparison of the loads obtained using “Appendix E of API STANDARD 650” of the American Petroleum Institute and the “Seismic Design of Storage Tanks” produced by the New Zealand Society for Earthquake Engineering. The seismic response assessed using both codes is presented for a range of tanks incorporating a range of the most relevant parameters in design. The results obtained from the analyses showed that both standards provide similar base shear and overturning moment; however, the results given for the anchorage requirement and uplift are different.
References
Haroun, M. A. (1983). Behavior of Unanchored Oil Storage Tanks: Imperial Valley Earthquake, Journal of Technical Topics in Civil Engineering, ASCE, 109(1), pp. 23-40.
Manos, G. C. and Clough, R. W. (1985). Tank Damage During the May 1983 Coalinga Earthquake, J. Earthquake Engrg. Struct. Dyn., 13(4), pp. 449-466. DOI: https://doi.org/10.1002/eqe.4290130403
Cooper, T. W. (1997). A Study of the Performance of Petroleum Storage Tanks during Earthquakes, 1933– 1995, NIST No. GCR 97-720, U.S. Dept. of Commerce, National Institute of Standards and Technology, Gaithersburgh, Md.
Housner, G. W. (1957). Dynamic Pressures on Accelerated Fluid Containers, Bulletin of the Seismological Society of America, 47, pp. 15-35.
Wozniak, R. S. and Mitchell, W. W. (1978). Basis of Seismic Design Provisions for Welded Steel Oil Storage Tanks. API Refining 43rd Mid-Year Meeting 1978, American Petroleum Institute (API), United States.
Veletsos, A. S. (1984). Seismic Response and Design of Liquid Storage Tanks. Guidelines for the seismic design of oil and gas pipeline systems, Technical Council on Lifeline Earthquake Engineering, ASCE, New York, pp. 255–370.
Jacobsen, L. S. (1949). Impulsive Hydrodynamics of Fluid Inside a Cylindrical Tank and of Fluid Surrounding a Cylindrical Pier, Bulletin of the Seismological Society of America, 39, pp. 189-204.
Larkin, T. (2008). Seismic Response of Liquid Storage Tanks Incorporating Soil Structure Interaction, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, 134(12), pp. 1804-1814.
Veletsos, A. S., Tang, Y. and Tang, H. T. (1992). Dynamic Response of Flexibly Supported Liquid-Storage tanks, J. of Structural Engineering, ASCE, 118(1), pp. 264-283. DOI: https://doi.org/10.1061/(ASCE)0733-9445(1992)118:1(264)
Malhotra, P. K. and Veletsos, A. S. (1994). Beam Model for Base Uplifting Analysis of Cylindrical Tanks, Journal of Structural Engineering, ASCE, 120(12), pp. 3471-3488.
Malhotra, P. K. (2000). Practical Nonlinear Seismic Analysis of Tanks, Earthquake Spectra, 16(2), pp. 473– 492.
Haroun, M. A. and Housner, G. W. (1982a). Dynamic Characteristics of Liquid Storage Tanks, Journal of the Engineering Mechanics Division, ASCE, 108(EM5), pp. 783-800.
Haroun, M. A. and Housner, G. W. (1982b). Complications in Free Vibration Analysis of Tanks, Journal of the Engineering Mechanics Division, ASCE, 108(EM5), pp. 800-818.
Haroun, M. A. and Ellaithy, A. M. (1985). Model for Flexible Tanks Undergoing Rocking, Journal of the Engineering Mechanics, ASCE, 111(2), pp. 143-157.
SEI/ASCE (2005). Minimum Design Loads for Buildings and Other Structures, 7-05, ASCE Standard.
NZS (2004). Structural Design Actions, Part 5: Earthquake Actions - New Zealand, NZS 1170.5, New Zealand Standard.
Veletsos, A. S. and Tang, Y. (1990). Soil-Structure Interaction Effects for Laterally Excited Liquid Storage Tanks, Earthquake Engineering and Structural Dynamics, 19, pp. 473-496.
Ishiyama, Y. (1984). Motion of Rigid Bodies and Criteria for Over-turning by Earthquake Excitation. Bulletin of NZNSEE, 17(1), pp. 24-37.
API (2007). Welded Steel Tanks for Oil Storage. API Standard 650, 11th Edition, American Petroleum Institute.
NZSEE (2009). Seismic Design of Storage Tanks - Recommendations of a Study Group of the New Zealand Society for Earthquake Engineering, NZSEE Standard.
