ASME B31Ea-2010 pdf download.Addenda to ASME B31E-2008 Standard for the Seismic Design and Retrofit of Above-Ground Piping Systems.
General. ASME Standards are developed and maintained with the intent to represent the consensus of concerned interests. As such, users ofthis Standard may interact with the Committee by requesting interpretations, proposing revisions, and attending Committee meetings. Corre- spondence should be addressed to: Secretary, B31 Standards Committee The American Society of Mechanical Engineers Three Park Avenue New York, NY 10016-5990 Proposing Revisions. Revisions are made periodically to the Standard to incorporate changes that appear necessary or desirable, as demonstrated by the experience gained from the application of the Standard. Approved revisions will be published periodically. The Committee welcomes proposals for revisions to this Standard. Such proposals should be as specific as possible, citing the paragraph number(s), the proposed wording, and a detailed description of the reasons for the proposal, including any pertinent documentation. Interpretations. Upon request, the B31 Mechanical Design Technical Committee will render an interpretation ofany requirementofthe Standard. Interpretations can onlybe rendered in response to a written request sent to the Secretary of the B31 Standards Committee. The request for interpretation should be clear and unambiguous. It is further recommended that the inquirer submit his/her request in the following format: Subject: Cite the applicable paragraph number(s) and the topic of inquiry. Edition: Cite the applicable edition of the Standard for which the interpretation is being requested. Question: Phrase the question as a request for an interpretation of a specific requirement suitable for general understanding and use, not as a request for an approval of a proprietary design or situation.
2 MATERIALS 2.1 Applicability This Standard applies to metallic ductile piping sys- tems, listed in the applicable ASME B31 Code section. 2.2 Retrofit The seismic retrofit of existing piping systems shall take into account the condition of the system and its restraints. As part of the seismic retrofit, the piping sys- tem shall be inspected to identify defects in the piping or its supports and current and anticipated degradation that could prevent the system from performing its seis- mic function. 3 DESIGN 3.1 Seismic Loading The seismic loading to be applied may be in the form of horizontal and vertical seismic static coefficients, or horizontal and vertical seismic response spectra. The seismic inputis to be specified by the engineering design in accordance with the applicable standard (such as ASCE 7) or site-specific seismic loading (para. 1.3). When the seismic design force is computed based on para. 13.3.1 of ASCE 7, or a similar standard, the parameter a p shall be 2.5 and the parameter R p shall not exceed 3.5 when applying the stress limits of para. 3.4. When the alternative design methods of para. 3.5 are used, the derivation of seismic inputs shall be based on parameters compatible with the design method being utilized. The seismic loading shall be specified for each of three orthogonal directions (typically plant east–west, north–south, and vertical). The seismic design should be based on either a three-directional excitation, east–west plus north–south plus vertical, combined by square-root sum of the squares (SRSS), or a two-directional design approach based on the envelope of the SRSS of the east–west plus vertical and north–south plus vertical seismic loading.