Reliability and optimization in seismic design

Isoreliable and minimum expected cost design spectra are derived in the paper, and their respective significance for the assessment of the structure's safety under seismic threat is discussed. The structural model used is a sdof non linear hysteretic oscillator, with stiffness- degrading properties, while the seismic action is modeled by means of a non stationary random process with peak ground acceleration as intensity parameter. The random quantities considered include the yield strength and the natural period of the model, the ground motion and its peak acceleration, and the values of the response variable defining the thresholds of the various limit states considered. The probabilities of attaining different response levels have been calculated by using a beta- index method in which the actual distribution of each variable is considered. Isoreliable design spectra giving a constant probability for the first attainment of different limit states are produced. Using poisson assumption, the total expected cost due to future monetary losses and to parametrically valued so called "intangibles" is calculated and, through a minimization procedure, a minimum expected cost design spectrum is produced. The reliability implied in this latter spectrum is finally assessed (a).


  • English

Media Info

  • Pagination: 714-29
  • Serial:
    • Volume: 2

Subject/Index Terms

Filing Info

  • Accession Number: 01438039
  • Record Type: Publication
  • Source Agency: ARRB
  • ISBN: 0909796076
  • Files: ATRI
  • Created Date: Aug 24 2012 9:20PM