Reference Sorce:
New seismic deisgn documents from about 1997 on have been tending toward significant increases in the design inertial load constants for piping and pressure vessels because of failures in some unrelated components and an extension of the design basis period. We are seeing Code documents in draft form that will increase seismic g loads by three times or more over values used in pre 1997 documents. This posting is to query is to see if anyone has experienced seismic failures of supports or piping components due purely, or at least in large part, to the inertial loading of the pipe. The majority of seismic failures that we have reviewed were caused by the relative movement of pipe or supports and not due to inertial loads. If this is universally the case, then increasing g loads is probably not the way to address these failures and will only serve to increase unnecessarily the cost of piping systems subject to seismic loads.
A more detailed outline of this query and design guidance for supports with seismic gaps is posted at on the downloads page.
Comments or references are appreciated.
Regards,
Tony Paulin
New seismic deisgn documents from about 1997 on have been tending toward significant increases in the design inertial load constants for piping and pressure vessels because of failures in some unrelated components and an extension of the design basis period. We are seeing Code documents in draft form that will increase seismic g loads by three times or more over values used in pre 1997 documents. This posting is to query is to see if anyone has experienced seismic failures of supports or piping components due purely, or at least in large part, to the inertial loading of the pipe. The majority of seismic failures that we have reviewed were caused by the relative movement of pipe or supports and not due to inertial loads. If this is universally the case, then increasing g loads is probably not the way to address these failures and will only serve to increase unnecessarily the cost of piping systems subject to seismic loads.
A more detailed outline of this query and design guidance for supports with seismic gaps is posted at on the downloads page.
Comments or references are appreciated.
Regards,
Tony Paulin
