The commentary to ASCE 7 quantifies the intended performance for buildings in different Risk Categories. Below The below Table summarizes the anticipated reliability values. These values have not been validated with experience or in-depth analysis, but instead are notional values that represent the intent of 48 the building code committee. FEMA P-695 (2009) also suggests that the probability of collapse due to MCER MCER ground motions should be limited to 10% for Risk Category II buildings. FEMA P-695 presents a detailed methodology for determining the collapse probability of classes of buildings. Several case studies have used the methodology to benchmark the performance of modern buildings, with results reported in in FEMA P-695 (2009)and and NIST (2010).
Risk Category | Probability of Total or Partial Collapse ( % ) | Probability of Failure that could result in endangerment of individual lives ( % ) |
|---|---|---|
I & II | 10 | 25 |
III | 6 | 15 |
IV | 2.5 | 10 |
Firstly, ASCE 7-16, the earthquake design values for most locations in the United States, have been adjusted so that structures having standard collapse fragility will have a collapse probability of 1% in 50 years.
According to ASCE 7-16, target reliability values for structural stability caused bu by an earthquake due to MCER MCER earthquake ground motion is given below.
Risk Category | Conditional Probability of Failure ( % ) | Conditional Probability of Component or Anchorage Failure ( % ) |
|---|---|---|
I & II | 10 | 25 |
III | 5 | 15 |
IV | 2.5 | 9 |
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