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Probabilistic Liquefaction Analysis

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Probabilistic Liquefaction Analysis NUREG/CR-6622 Probabilistic Liquefaction Analysis U.S. Army Corps of Engineers U.S. Nuclear Regulatory Commission Office of Nuclear Regulatory Research Washington, DC 20555-0001 AVAILABILITY NOTICE Availability of Reference Materials Cited in NRC Publications series, NRC regu NRC Public Document Room NRC publications in the NUREG 2120 L Street, N.W., Lower Level 10, energy, of the Code of Federal lations, and Title Washington, DC 20555-0001 may be purchased from one of the fol Regulations, <http://www.nrc.gov/NRC/PDR/pdrl.htm> lowing sources: 1-800-397-4209 or locally 202-634-3273 1. The Superintendent of Documents Microfiche of most NRC documents made publicly Government Printing Office U.S. available since January 1981 may be found in the PO. Box 37082 Local Public Document Rooms (LPDRs) located in Washington, DC 20402-9328 the vicinity of nuclear power plants. The locations <http://www.access.gpo.gov/sudocs> of the LPDRs may be obtained from the PDR (see 202-512-1800 previous paragraph) or through: Technical Information Service 2. The National <http://www.nrc.gov/NRC/NUREGS/ Springfield, VA 22161 -0002 SR1350N9/lpdr/html> <http://www.ntis.gov/ordernow> 703-487-4650 Publicly released documents include, to name a few, NUREG-series reports; Federal Register no The NUREG series comprises (1) brochures tices; applicant, licensee, and vendor documents (2) proceedings of confer (NUREG/BR-XXXX), correspondence; NRC correspondence and (3) reports resulting and ences (NUREG/CP-XXXX), internal memoranda; bulletins and information no from international agreements (NUREG/IA-XXXX), tices; inspection and investigation reports; licens administrative reports and books (4) technical and reports; and Commission papers and and (5) ee event [(NUREG-XXXX) or (NUREG/CR-XXXX)], their attachments. compilations of legal decisions and orders of the Commission and Atomic and Safety Licensing Documents available from public and special tech Boards and of Office Directors' decisions under nical libraries include all open literature items, such Section 2.206 of NRC's regulations (NUREG as books, journal articles, and transactions, Feder XXXX). al Register notices, Federal and State legislation, and congressional reports. Such documents as each NRC draft report is available A single copy of theses, dissertations, foreign reports and transla supply, upon written request free, to the extent of tions, and non-NRC conference proceedings may as follows: be purchased from their sponsoring organization. Office of the Chief Information Officer Address: Copies of industry codes and standards used in a Reproduction and Distribution manner in the NRC regulatory process Services Section substantive are maintained at the NRC Library, Two White Flint U.S. Nuclear Regulatory Commission North, 11545 Rockville Pike, Rockville, MD Washington, DC 20555-0001 20852-2738. These standards are available in the E-mail: <[email protected]> library for reference use by the public. Codes and Facsimile: 301 -415-2289 standards are usually copyrighted and may be A portion of NRC regulatory and technical informa purchased from the originating organization or, if tion is available at NRC's World Wide Web site: they are American National Standards, from <http://www.nrc.gov> American National Standards Institute 11 West 42nd Street to the public are avail All NRC documents released New York, NY 10036-8002 for a fee, in paper, able for inspection or copying <http://www.ansi.org > cases, diskette, from the microfiche, or, in some 212-642-4900 Public Document Room (PDR): DISCLAIMER any legal liability or responsibility for any third party's use, or the This report was prepared as an account of work sponsored by results of such use, of any information, apparatus, product, or Neither the United an agency of the United States Government. process disclosed in this report, or represents that its use by any of their em States Government nor any agency thereof, nor such third party would not infringe privately owned rights. ployees, makes any warranty, expressed or implied, or assumes NUREG/CR-6622 Probabilistic Liquefaction Analysis Manuscript Completed: October 1999 Date Published: November 1999 Prepared by M. E. Hynes U.S. Army Corps of Engineers 3909 Halls Ferry Road Vicksburg, MS 39180-6199 E. G. Zurflueh, NRC Project Manager Prepared for Division of Engineering Technology Office of Nuclear Regulatory Research U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 NRC Job Code W6246 Probabilistic Liquefaction: ;nalysis ABSTRACT This document provides a technical basis for formulating probabilistic approaches to liquefaction evalu ation. The three basic elements of probabilistic liquefaction analysis are described: (1) uncertainty in the earthquake load, (2) uncertainty in the available resistance, and (3) uncertainty in the method of analysis. The probabilistic approach is built from the steps in a deterministic liquefaction analysis; however, the input parameters, such as penetration resistance, site stratigraphy, acceleration, and magnitude, are treated as random variables and the accuracy of the method of analysis is factored in as part of a capacity-demand model. Uncertainty in the earthquake load is generally treated with a probabilistic seismic hazard analysis which introduces time as a parameter. The site stratigraphy and engineering properties are generally treated as one-, two-, or three-dimensional random fields. Uncertainty in the method of analysis is generally estimated with logit regression analysis of the field performance data base. It is assumed that the reader has a working knowledge of probability theory, stochastic processes, liquefaction evaluation, and probabilistic seismic hazard analysis calculations. iii N NUREG/CR-6622 Probabilistic Liquefaction Analysis TABLE OF CONTENTS A B STR A C T ........................................................................ iii PREFA CE ......................................................................... vi 1 IN TRODU CTION ................................................................. 1 2 UNCERTAINTY IN EARTHQUAKE LOAD ........................................... 1 2.1 A pparatus .................................................................... 1 2.2 Probabilistic Site Response ...................................................... 2 2.3 Artificial Earthquake Records .................................................... 3 3 UNCERTAINTY IN LIQUEFACTION RESISTANCE .................................... 3 3.1 Calculation of Liquefaction Resistance ............................................ 3 3.2 Spatial M odeling of the Soil Deposit ............................................... 5 4 UNCERTAINTY IN METHOD OF LIQUEFACTION ANALYSIS .......................... 6 4.1 Uncertainty in the Seed-Idriss Chart ............................................... 6 4.2 Other Types of Analysis and Inputs ............................................... 13 4.2.1 Cone Penetration Test .................................................... 13 4.2.2 Shear Wave Velocity, Becker and Large Penetrometer Tests ..................... 13 4.2.3 Arias Intensity and SPT .................................................. 13 4.2.4 Liquefiable Fine-Grained Soils ............................................. 14 4.2.5 Steady-State Liquefaction Evaluation ........................................ 14 4.2.6 Advanced Constitutive Models and Deformation Codes ......................... 14 5 CAPACITY-DEMAND MODEL .................................................... 16 6 DISCUSSION AND CLOSURE ..................................................... 19 REFERENCES ..................................................................... 22 APPENDIX A BIBLIOGRAPHY .................................................... A-1 LIST OF FIGURES Figure 4.1. Logit results for sands with <12 percent fines after Liao et al. (1988) and Liao (1996) (figure from Youd and Noble 1997) ................................................. 8 Figure 4.2. Logit results for sands with >12 percent fines after Liao et al. (1988) and Liao (1996) (figure from Youd and Noble 1997) ................................................. 8 Figure 4.3. Logit results from Youd and Noble (1997) ...................................... 9 Figure 4.4. Liao et al. (1988) and Youd and Noble (1997) logit results plotted against Seed et al. (1985) curve for clean sands (after Youd and Noble 1997) ............................... 10 Figure 4.5. Interim logit results from Dr. Seed (1998) for clean sands ......................... 11 Figure 4.6. Interim logit results from Dr. Seed (1998) for <5, 15, and >35 percent fines ........... 12 Figure 4.7. Logit results for Arias Intensity (this study) from data by Kayen and Mitchell (1997) .... 15 V NUREG/CR-6622 Probabilistic Liquefaction Analysis Figure 5.1. Triggering combination of peak ground acceleration and magnitude given N,,,o . 17 Figure 5.2. Deaggregated PSHA hazard curves for example problem .......................... 18 Figure 5.3. Approach to determine annual probability of liquefaction using Arias Intensity ........ 21 LIST OF TABLES Table 5.1 Probability of Liquefaction Calculation for Example Problem ....................... 20 NUREG/CR-6622 vi Probabilistic Liquefaction Analysis PREFACE The study described in this report was performed by the U.S. Army Engineer Waterways Experiment Station (WES) for the U.S. Nuclear Regulatory Commission (NRC) under Inter-Agency Agreement RES-95-008 during the period June, 1995, to January, 1999. The study was directed by Mr. Robert
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