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40 APPENDIX A Survey Questionnaire Page One--General questions 1.) Dear Colleague: The Transportation Research Board (TRB) is preparing a synthesis on Practice and Procedures for Site-Specific Evaluation of Earthquake Ground Motions, NCHRP Synthesis 20-05/Topic 42-03, State DOT's Survey. This is being done for NCHRP, under the sponsorship of the American Association of State Highway and Transportation Officials, in cooperation with the Federal Highway Administration. The synthesis study intends to identify and describe current practice and available methods for site specific analysis of earthquake ground motions. The study will include a summary of experience gained in developing and employing these methods, including challenges in their application and perceived advantages and disadvantages of the different methods. This study will help establish and improve the state of practice, providing a summary of best design practices, as well as identifying research and development needs on this important topic. This questionnaire will help us understand the current practice in site specific analysis of ground motions at selected state departments of transportation and will help us identify some of the challenges encountered when con- ducting the analyses. We appreciate you taking the time to complete this survey. Please do not hesitate to contact us should you have any questions. As a token of our appreciation we will provide you electronically with a copy of the completed study. The results of this study will be reported only in aggregate form (no individual names will be reported). This survey is being sent to state departments of transportation and their consultants. Your cooperation in completing the questionnaire will ensure the success of this effort. If you are not the appropriate person at your agency to complete this survey, please forward it to the correct person. Please compete and submit this survey by COB Friday, February 25, 2011. We estimate that it should take no more than 60 minutes to complete. If you have any questions, please contact our principal investigator Dr. Neven Matasovic (NMatasovic@ Geosyntec.com, 714-465-1244) or Prof. Youssef Hashash (hashash@illinois.edu, 217-333-6986). Any supporting materials can be sent directly to by e-mail or at the postal address shown at the end of the survey. QUESTIONNAIRE INSTRUCTIONS 1. To view and print the entire questionnaire, Click on the following link and print using "control p". 2. To save your partial answers, or to forward a partially completed questionnaire to another party, click on the "Save and Continue Later" link in the upper center of your screen on page 2 and onwards. A link to the partial survey will be e-mailed to you or a colleague. 3. To view and print your answers before submitting the survey, click forward to page 8. Print using "control p". 4. To submit the survey, click on "Submit" on the last page. Name of Respondent: ____________________________________________ Title of Respondent: _____________________________________________ Name of State Agency and office: __________________________________ Address: ______________________________________________________ E-mail: _______________________________________________________ Telephone number: ______________________________________________

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41 2.) Do your following responses apply to (check all that applies)? [ ] Your own individual practice [ ] The practice of your office/number of engineers [ ] The practice of your agency/number of engineers 3.) Approximately how many of your projects involve site response analyses in a given year? ( ) 12 ( ) 36 ( ) 712 ( ) 1325 ( ) 2650 ( ) >50 4.) Guidelines and manuals for seismic site response [ ] Your agency has a manual for seismic design; please provide title and web link [ ] Your manual has provisions for seismic site response analysis/provide title and web link Page Two--Criteria and programs used 5.) When is the use of code-based site factors acceptable for characterizing site effects? [ ] Preliminary design [ ] Small structures [ ] Seismic hazard is low [ ] Always [ ] Never [ ] Other--please provide a brief narrative 6.) When is the use of computer analysis required for site response analysis? [ ] Site class dependent--please list site class [ ] Seismic hazard level--please specify [ ]Ground conditions (e.g., liquefiable soils, or organic soils, or very soft soils subjected to strong shaking, please specify) [ ] Structure type--please specify [ ] Other--please describe 7.) Of the total number of site response analyses you perform, indicate the approximate percentages that fall within each of the following categories: One-dimensional equivalent-linear: _________________________________ One-dimensional nonlinear total stress (no pore water pressure): __________ One-dimensional nonlinear effective-stress (with pore water pressure): ____ Two- or three-dimensional equivalent-linear: _________________________ Two- or three-dimensional nonlinear Total Stress Analysis: ______________ Two- or three-dimensional nonlinear Effective-Stress Analysis: __________

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42 8.) What computer program(s) do you use for each of the following types of analyses (list more than one if appropriate; leave blank if you do not perform one of these types of analyses)? One-dimensional equivalent-linear: _____________________________________________ One-dimensional nonlinear--Total stress (no pore water pressure): ____________________ One-dimensional nonlinear--Effective-stress (with pore water pressure): ______________ Two- or three-dimensional equivalent-linear: _____________________________________ Two- or three-dimensional nonlinear: ___________________________________________ 9.) Please describe validation/verification requirements you have for computer code usage. Page Three--Seismic hazard motion input required for site response analysis Note for the following questions: Input ground motions are required for performing site response analysis based on specific hazard levels. The questions below will help us understand how you develop these ground motions. 10.) How do you define the seismic hazard at your site and the target rock response spectra? [ ] USGS Maps [ ] Code Provision--List code [ ] Site specific deterministic--describe program [ ] Site specific probabilistic--describe program [ ] Other, please specify: 11.) How do you develop hazard compatible ground motion time histories at rock? [ ] Simple scaling of motions from widely available libraries [ ] rigorous spectral matching (specify method if known) [ ] Synthetic ground motions [ ] Other, please specify: 12.) How many motion time histories do you generate or require for a given hazard level ( ) 1 motion ( ) 3 motions ( ) 7 motions ( ) Other, please specify: 13.) For sites where near faults effects are significant, what special requirements do you impose on the suite of input ground motions? [ ] None [ ] incorporate directivity [ ] include velocity pulse [ ] use two component motions (e.g., Fault normal/parallel) [ ] check cross-correlation of the input ground motion time histories [ ] Other, please specify:

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43 14.) How do you handle uncertainty in the input ground motion? 15.) Please include other comments you may have related to the topic of input motions. Page Four--Soil profile input information required for site response analysis 16.) What special geotechnical field and laboratory investigations do you require/perform to obtain information suitable for site response analysis? [ ] None [ ] Direct measurement of shear wave velocity [ ] Cyclic triaxial, direct simple shear or resonant column tests [ ] Other, please specify: 17.) How do you obtain the shear wave velocity profile for the soil column? [ ] SPT correlations [ ] CPT correlations [ ] Seismic cone [ ] downhole [ ] crosshole [ ] suspension logger [ ] surface wave/SASW/MASW [ ] Other, please specify: 18.) How do you define the dynamic soil properties (modulus reduction and damping curves) for site response analysis? (lab testing, published correlations based soil index properties such as Darandelli, Vucetic and Dobry, Seed and Idriss...) [ ] laboratory testing [ ] Darendeli [ ] Vucetic-Dobry [ ] Seed-Idriss [ ] Other, please specify: 19.) Do you account for uncertainty in the soil profile properties? If yes, how? If not, why not? 20.) Please include other comments you may have related to the topic of soil profile input Page Five--Site response analysis 21.) When is an equivalent-linear analysis (e.g., SHAKE or similar program) used or required? [ ] Site class dependent--please list site class [ ] Seismic hazard level--please specify [ ] Structure type--please specify [ ] Other, please describe: 22.) What soil models do you usually use for equivalent-linear site response analyses (mark all that applies)? [ ] EPRI [ ] Ishibashi-Zhang

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44 [ ] Iwasaki [ ] Seed-Idriss Sand [ ] Seed-Idriss Clay [ ] Vucetic-Dobry [ ] Darendeli [ ] Other: 23.) When is a nonlinear total stress (no pore water pressure generation) analysis used or required? [ ] Site class dependent--please list site class [ ] Seismic hazard level--please specify [ ] Structure type--please specify [ ] Strain amplitude--please specify [ ] Other, please describe: 24.) What soil models do you usually use for nonlinear total stress site response analyses (mark all that applies)? [ ] Hyperbolic with Masing criteria [ ] Modified Hyperbolic with Masing criteria (e.g., M-K-Z) [ ]Modified Hyperbolic with non Masing criteria (e.g., MRDF to match both modulus reduction and damping curves) [ ] Cundall-Pyke model [ ] Mohr-Coulomb [ ] Other--whatever model is included in my software--please specify: [ ] It is important for the model to match both modulus reduction and damping curves [ ] It is only important that the model matches modulus reduction regardless of the damping curve. 25.) When is a nonlinear effective-stress (with pore water pressure generation) analysis used or required? [ ] Site class dependent--please list site class [ ] Seismic hazard level--please specify [ ] Structure type--please specify [ ] When porewater pressure ratio exceeds a given value--please specify [ ] Other, please describe: 26.) What soil models and porewater pressure generation models do you use in nonlinear effective-stress site response analyses (mark all that applies)? [ ] Dobry [ ] Elgamal [ ] GMP (Green) [ ] Martin-Finn-Seed [ ] Matasovic (Modified Dobry et al. porewater pressure model) [ ] UBC Sand [ ] Other

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45 Page Six--Evaluation and use of results 27.) What do you consider to be the top three uncertainties in the input to a typical seismic site response analysis? [ ] Low-strain stiffness (represented by Gmax or Vs) [ ] Higher strain stiffness (represented by modulus reduction or backbone curve) [ ] Small strain damping behavior represented by viscous damping [ ] Large strain damping behavior (represented by damping curve or unloading-reloading model) [ ] Soil layer thickness [ ] Depth to bedrock [ ] Character of bedrock (Vs, modulus reduction and damping behavior) [ ] Input motions [ ] Other: 28.) How do you typically account for such uncertainties in design? [ ] Select reasonably conservative values of input parameters [ ] Use "best estimate" input parameters, then apply conservatism to results [ ] Perform sensitivity analyses [ ] Perform probabilistic analyses (e.g. FOSM, Monte Carlo) [ ] We don't address uncertainties explicitly [ ] Other, please specify: 29.) How do you evaluate the validity of the overall site response model at your site? [ ] Compare with empirical correlations [ ] Perform sanity checks [ ] Other, please specify: 30.) What output do you use from site response analysis? [ ] Surface response spectra [ ] Surface velocities [ ] Surface displacements [ ] Surface time histories [ ] Profiles of PGA [ ] Profiles of strains [ ] Profiles of displacements [ ] Profiles of shear stress [ ] Other, please specify:

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46 31.) Do you use output of profiles of strains and lateral deformations in a structural analysis? (e.g., pile lateral loading...), please explain, do you perform any baseline correction of the output motions? 32.) Do you use profile of peak ground acceleration for liquefaction analysis? Please explain. When you evaluate cyclic stress ratio (CSR) for liquefaction analyses, how often do you do so by means of site response analyses (as opposed to using the simplified method)? What criteria do you use for deciding when to do so? 33.) Do you use profile of peak ground acceleration for slope stability analysis? Please explain. 34.) For analyses where pore water pressure generation is evaluated, how do you use the analysis output? 35.) Please include other comments you may have related to the topic on evaluation and use. Page 7--Helpful contacts 36.) As part of this synthesis study we will also survey private consulting firms and engineers who conduct site specific response analysis. Can you please provide us with contact information of key firms and engineers that provide site response analysis services to your DOT? Firm Name Contact Person Contact information Contact 1 ___ ___ ___ Contact 2 ___ ___ ___ Contact 3 ___ ___ ___ Contact 4 ___ ___ ___ Contact 5 ___ ___ ___ Contact 6 ___ ___ ___ Contact 7 ___ ___ ___ Contact 8 ___ ___ ___ Contact 9 ___ ___ ___ Contact 10 ___ ___ ___ 37.) Please feel free to include any thoughts or comments you would like to share with us. Thank You! Thank you for taking our survey. Your response is very important to us. Postal address: Dr. Neven Matasovic Geosyntec 2100 Main St, Suite 150 Huntington Beach, CA 92648