ASME B31E-2008 pdf free download.Standard for the Seismic Design and Retrofit of Above-Ground
Piping Systems.
3.7.2 The seismic adequacY of seismic restraints shall be determined on the basis of vendor catalogs, and the applicable design method and standard, such as MSS SP-58 or MSS SP-69 for standard support conponcnts, AISC or AISI for steel members, and Ad for concrete anchor bolts. The qualiFication of seismic restraints shaLl also address the prevention of buckling.
3.7.3 The seismic adequacy of nonseismic restraints shall also be verified If they are espected to perform a ftmction after the earthquake. For esample, spring hangers should not be permitted to pull off the wall if they are necessary to support the pipe weight after the earthquake.
3.7.4 For lateral seismic restraints, a total diametric gap equal to In. (12 mm) Is acceptable. A gap up to 0.1 L) or 2 in. (50 mm), whichever is smaller, is permitted, provided the seismic load, calculated on the basis of zero gap, is multiplied by an impact factor of 2. Larger gaps or smaller impact (actors may be justified by analysis or test.
3.7.5 Short rod hangers Itypically less than 12 in. (300 mm) longi may provide a restoring force that tends to limit side-sway of hung pipe. and may be considered as seismic restraints, provided they are designed to sustain the seismic loads and movements.
3.8 Equipment and Components
The seismic and concurrent loads applied by the pipe at equipment and component nozzles shall be qualified as part of the seismic design or retrofit of the piping system, to a degree comniensurate with the required system function, as specified in para. 1.3.
For position retention, it is usually sufficient to show that the piping loads on equipment and components will not cause rupture. For leak tightness, the stress shall be maintained within yield or shown not to cause fatigue ruptures. For operabilitc the piping loads shall be kept within operability limits established by detailed analysis, testing, or similarity to seismically qualified equipment or components.
Components with unsupported estended structures, such as valve with heavy motor operators, shall he evaluated to insure that the extended structure does not fail during a seismic event. For components with unsupported e,tended structures, a natural frequency check shall be performed and shall be greater than 33 l,,%rhen the natural frequency Is less than 33 Hz, the component extended structure shall be stiffened as recommended by the component manufacturer 4 INTERACTIONS
Piping systems shall be evaluated for seismic interactions. Credible and significant interactions shall be identilled and resolved by analysis testing, or hardware misliuication.
S DOCUMENTATION
The engineering design shall specify the docunientation to be submitted by the designer
6 MAINTENANCE
The piping system shall be maintained in a condition that meets the seismic design requirements for the operating lifc of the system. In particular, changes to layout, supports. components, or function, as well as material degradation in service shall be evaluated to verif the continued seismic adequacy of the system.
7 REFERENCES
The following is a list of publications referenced in this Standard. The latest edition shall apply.
ACI 318 Building Code Requirements for Reinforced Concrete
Publisher: American Concrete Institute (ACI), 38800 Country Club Drive, Farmington Hills, Ml 48331 AISC. Manual of Steel Construction Publisher: American Institute of Steel Construction (AISC), One East Wacker Drive, Chicago, IL 60601-1802
AISI, Specification for the Design of Cold-Formed Sled Structural Members.