Example 3610

Based on the classification system above, categorize the redundancy of the truss shown in Example 36.9. Answer

«system = 4.19 — 3.48 = 0.71 g system = 7.42 — 3.48 = 3.94

Since gsystem > «system > 0, the truss structure is classified as redundant.

36.5 Damage and Deterioration

A life cycle cost analysis for a structure requires a number of assumptions about the loading, resistance, and deterioration. In general, a structure will begin to deteriorate and experience reliability reduction from the day it is placed in service. A predictive model is needed to estimate how the loads and resistances will change over time. The deterioration model is usually derived theoretically, obtained from laboratory data, or extrapolated from the behavior of similar structures under similar conditions. These models predict future performance over several decades and are the basis for optimum life cycle inspection and repair planning. Common deterioration mechanisms include corrosion, fatigue, rotting, and spalling, among others.

0 0

Post a comment