Example 3615

The retaining wall in the previous example has survived and performed well without maintenance for 19 years. In developing his annual budget, the owner is trying to decide whether this is a cost-effective time to replace the support beams in the structure. The replacement cost for new supporting beams is $67,000. The new support beams are expected to have a service life of 20 years before they would need replacing again. The discount rate r is 6%. If the wall fails, there are several possible consequences as follows: (a) There is a 30% chance that the wall will simply bow excessively and there will be long-term

TABLE 36.3 The Hazard Function H( t) for the Support Beams in a Retaining Wall That Is Deteriorating Due to Corrosion

Hazard

Reliability Probability of Probability of Derivative function

Year index (b) failure (pf) survival (ps) (dps/dt) (H(t)) Best fit H(t)

Hazard

Reliability Probability of Probability of Derivative function

Year index (b) failure (pf) survival (ps) (dps/dt) (H(t)) Best fit H(t)

0 0

Post a comment