1、Designation: E2557 07E2557 16 An American National StandardStandard Practice forProbable Maximum Loss (PML) Evaluations for EarthquakeDue-Diligence Assessments1,2This standard is issued under the fixed designation E2557; the number immediately following the designation indicates the year oforiginal
2、adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice establishes standard-of-care for evaluation and classi
3、fication of the financial risks from earthquake damage toreal estate improvements for use in financial transactions. mortgage transactions and capital investment evaluation. As such, thispractice permits a user to satisfy, in part, their real estate transaction due-diligence requirements with respec
4、t to assessing andcharacterizing a propertys potential losses from earthquakes. This practice is intended to address only physical damage to theproperty from site and building response.1.1.1 Hazards addressed in this practice include earthquake ground shaking, earthquake-caused site instability, inc
5、ludingfaulting, subsidence, settlement landslides and soil liquefaction, earthquake-caused tsunamis and seiches, and earthquake-causedflooding from dam or dike failures.1.1.2 Earthquake-caused fires and toxic materials releases are not hazards considered in this practice.1.1.3 This practice does not
6、 purport to provide for the preservation of life safety, or prevention of building damage associatedwith its use, or both.1.1.3.1 This practice does not address requirements of any federal, state, or local laws and regulations of building constructionor maintenance. Users are cautioned that current
7、federal, state, and local laws and regulations may differ from those in effect atthe times of construction or modification of the building(s), or both.1.1.3.2 This practice does not address the contractual and legal obligations between prior and subsequent Users of PMLseismicrisk assessment reports
8、or between providers who prepared the report and those who would like to use such prior reports.1.1.3.3 This practice does not address the contractual and legal obligations between a provider and a user, and other parties, ifany.1.1.4 It is the responsibility of the owner of the building(s) to estab
9、lish appropriate life-safety and damage prevention practicesand determine the applicability of current regulatory limitations prior to use.1.2 Considerations not included in the scope: the impacts of damage to building contents, loss of income(s), rents, or othereconomic benefits of use of the prope
10、rty, or from legal judgments, fire sprinkler water-induced damage or fire.1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information only and are not considered standard.2. Refere
11、nced Documents2.1 ASTM Standards:3E2026 Guide for Seismic Risk Assessment of Buildings2.2 Other Standards:4UBC-97 UnifromUniform Building Code, 1997 EditionInternational Building CodeIBC 2006 EditionInternational Building Code, current edition1 This practice is under the jurisdiction ofASTM Committe
12、e E06 on Performance of Buildings and is the direct responsibility of Subcommittee E06.25 on Whole Buildingsand Facilities.Current edition approved May 1, 2007Jan. 1, 2016. Published May 2007June 2016. Originally approved in 2007. Last previous edition approved in 2007 as E2557-07.DOI: 10.1520/E2557
13、-07.10.1520/E2557-16.2 Portions of this publication reproduce content from the 1997 Uniform Building Code, International Code Council, Inc.Inc., Falls Church, Virginia. Reproduced withpermission. All rights reserved.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM
14、Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.4 Available from International Organization for Standardization (ISO), 1 rue de Varemb, Case postale 56, CH-1211, Geneva 20, Switzerland, http:/w
15、ww.iso.ch.CodeCouncil (ICC), 500 New Jersey Ave., NW, 6th Floor, Washington, DC 20001, http:/www.iccsafe.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be t
16、echnically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive,
17、PO Box C700, West Conshohocken, PA 19428-2959. United States12.3 ASCE Standards:5ASCE 7 Minimum Design Loads for Buildings and Other StructuresStructures, current editionASCE 31 Seismic Evaluation of Existing BuildingsASCE 41 Seismic Rehabilitation Evaluation and Retrofit of Existing BuildingsBuildi
18、ngs, current edition3. Terminology3.1 See also definitions in Guide E2026.3.2 475-year site ground motions, nseismic induced ground motions at a site with approximately: a return period of 475 years,a 10 % probability of exceedance in 50 years, and an annual frequency of 0.21 %. Also referred to as
19、the DBE.3.3 DBE, field assessor, nDesign Basis Earthquake, field assessor, as defined in Guide E2026.3.4 lateral load-resisting system, independent reviewer, nLateral Load Resisting System, independent reviewer, as defined inGuide E2026.3.5 MCE, lateral load-resisting system, nMaximum Capable Earthq
20、uakelateral load-resisting system, as defined in GuideE2026.3.6 PML,MCE, nTerm historically used to characterize building damageability in earthquakes.Maximum Capable Earthquake,as defined in Guide E2026.3.5.1 DiscussionProbable maximum loss, shall be defined by the user from SL or PL values using d
21、efinitions of Guide E2026. For SL-basedmeasures include in the report the specified earthquake or ground motion for which it is to be evaluated and stipulate whether itis an expected value (SEL) or upper value (SUL). For PL-based measures, the return period for non-exceedance shall be specified,or t
22、he probability of exceedance in a given time period provided.3.7 probable loss (PL), nProbable Lossprobable loss, as defined in Guide E2026.3.7.1 DiscussionWhen there are multiple buildings in the seismic risk assessment, then the damageability values for the group of buildings is tobe determined as
23、 specified in Guide E2026.3.8 provider, probable maximum loss (PML), norganization and individual that completes the seismicprobable maximum loss,as defined in Guide E2026risk assessment3.9 scenario loss (SL), provider, nAs provider, as defined in Guide E2026.3.8.1 DiscussionWhen multiple buildings
24、are in the seismic risk assessment, then the SL for the group of building is to be determined as specifiedin Guide E2026.3.10 SEL, scenario expected loss (SEL), nAs scenario expected loss, as defined in Guide E2026.3.10.1 DiscussionWhen there are multiple buildings in the assessment then the SEL for
25、 the group of buildings is to be determined as specified inGuide E2026., Section 5.3.3.10 SELDBE, nThe scenario expected loss due to the occurrence of DBE site ground motions.3.11 SELMCE, nThe scenario expected loss due to the occurrence of MCE site ground motions.3.11 significant damage, scenario l
26、oss (SL), nDamage costs that exceeds five percentscenario loss, as defined in GuideE2026of the replacement cost of construction for the building caused by site failure from soil liquefaction, landsliding, or otherearthquake-induced site response other than shaking. Damage cost for this purpose inclu
27、des the cost of the site topography awayfrom the building3.11.1 Discussion5 Available from American Society of Civil Engineers (ASCE), 1801 Alexander Bell Dr., Reston, VA 20191, http:/www.asce.org.E2557 162Conditions resulting from lack of routine maintenance, miscellaneous repairs, operating mainte
28、nance, and so forth are notconsidered a deficiency. The damage is not significant if it does not affect the structural elements of the building because themovement is not substantial or the foundation is resistant to settlement-induced damage. Damage limited to undergroundWhenmultiple buildings are
29、in the seismic risk assessment, then the SL for the group of buildings is to be determined as specified inGuide E2026utilities or slabs on grade is not significant., Section 5.3.3.12 SUL, scenario upper loss (SUL), nAs scenario upper loss, as defined in Guide E2026.3.12.1 DiscussionWhen there are mu
30、ltiple buildings in the assessment then the SUL for the group of buildings is to be determined as specified inGuide E2026., Section 5.3.3.13 SULSEL475,DBE, nThethe scenario upperexpected loss due to the occurrence of DBE 10 %/50-year site ground motions.3.14 SULSELMCE, nThethe scenario upperexpected
31、 loss due to the occurrence of MCE site ground motions.3.15 third party,senior assessor, nA technically qualified individual and organization that has not been engaged in theseniorassessor, as defined in Guide E2026design or modifications of the building(s), and is not part of the due- diligence tea
32、m thatprovided the earthquake loss assessment3.16 significant damage, nsignificant damage, as defined in Guide E20263.17 SUL475, nthe scenario upper loss due to the occurrence of 10 %/50-year site ground motions.3.18 SULMCE, nthe scenario upper loss due to the occurrence of MCE site ground motions.4
33、. Summary of Practice4.1 The objectives of this practice are as follows:4.1.1 To synthesize and document good commercial practice for the determination and rating of seismic risk for buildings.4.1.2 To facilitate standardization of earthquake risk evaluation terminology for financial transactions.4.
34、1.3 To establish an industry standard for the requirements to evaluate the financial risk for real estate.5. Significance and Use5.1 This practice is intended for use as a voluntary standard by parties who wish to undertake the seismic risk assessment ofproperties.The goal is for users to objectivel
35、y and reliably compare the financial risks of earthquake damage to buildings, or groupsof buildings, on a consistent basis.5.2 This practice is designed to provide requirements for the evaluation of earthquake damage risk so that technical reportsprepared for the evaluation and rating of seismic ris
36、k of a building(s) will be adequate for use by other entities. Potential usersincluding, but are not be limited to, those making equity investments, lending, and financial transactions, including securitizedmortgage lending by mortgage originators, loan servicers, underwriters, rating agencies, and
37、purchasers of bonds secured by thereal estate.5.3 The use of this practice may permit a user to satisfy, in part, their requirements for due diligence in assessing a propertyspotential for losses associated with earthquakes for real estate transactions.6. Due-Diligence Investigation6.1 The site stab
38、ility, building stability and building damageability of the property shall be assessed.6.2 The user shall specify the condition of the property to be evaluated. The seismic performance can be evaluated for theproperty in its current condition, or as changed by proposed modification of the seismic re
39、sponse of the soils supporting thebuilding or a proposed seismically retrofitted condition of the building(s) or its sections, or both.any combination of theseconditions.6.2.1 The proposed seismic modifications of the site must be sufficiently described to allow evaluation of the modifications byan
40、independent qualified party.Independent Reviewer.6.2.2 The proposed seismic modifications of the building systems must be sufficiently described to allow evaluation of themodifications by a qualified third party.an Independent Reviewer.6.3 The Guide E2026 level of investigation shall be specified by
41、 the user. The same level of investigation should be performedfor each type of the seismic risk assessment. Appendix X1 gives guidance on the setting of the level of investigation.6.4 The qualifications of the providerProvider shall be specified as required for the level of investigation specified i
42、n 6.3 by6.3of Guide E2026. The qualifications level must be equal to or higher than the corresponding level specified in 6.3.6.2 Appendix X1gives further guidance on the setting of minimum qualifications.and 6.3.6.4.1 For an assessment of Level 1 or higher, the qualifications of Senior Assessor and
43、the Field Assessor of the property andits buildings shall be those of Guide E2026 Sections 6.2.3.2 and 6.2.3.3.E2557 1636.4.2 Notwithstanding the asserted level of investigation of a report, if the Senior Assessor or the Field Assessor, or both, donot demonstrate the qualifications of Guide E2026 Se
44、ction 6.2.3.2 and 6.2.3.3, then the report shall be designated a Level 0 report.6.5 PML Seismic Risk Assessment ReportThe findings shall be reported in conformance to the requirements of Guide E2026for the level of investigation specified by the user in 6.3 and by a provider qualified in accordance
45、with the requirements of 6.4,with the following sections:6.5.1 A summary that contains the conclusions of the seismic risk assessment:6.5.1.1 Location of the building(s) and building(s), characterization of the site and site soils, and gravity and lateralload-resisting systems.6.5.1.2 Stability dete
46、rmination of each building site under consideration when subjected to the seismic loadings for the buildingsite location and building characteristics and for the level of investigation specified as set forth in Section 9 of Guide E2026. Sitestability determination need only be qualitative in nature
47、for an SS0 investigation. For SS1 investigations the site stability is aqualitative assessment that includes the implications on damage to the building structural elements. For SS2 and SS3 investigationsthe site should be considered unstable if significant damage is caused to the building by the sit
48、e instability.6.5.1.3 Stability determination of each building under consideration in the seismic loadings for the building site location andbuilding characteristics and for the level of investigation specified, as set forth in Section 8 of Guide E2026.6.5.1.4 The PML value building damageability va
49、lues for the building or group of buildings as a whole, if there are multiplebuildings in the seismic risk assessment and for the levelwhole for the level of investigation specified as set forth in Section 10of Guide E2026of investigation specified(1) For commercial mortgage backed securities the PML is defined as PML shall be user-defined.At a minimum, the SELDBE.and SULDBE shall be reported.(2) For other applications the PML shall be user-defined.NOTE 1CMBS industry is currently defining PML as SELDBE. It is advisable that SEL and SUL values also
