The American Society of Civil Engineers (ASCE) has developed a national standard entitled the Seismic Evaluation of Existing Buildings (ASCE 31-03). The value this standard provides is that a building need not be evaluated by the more stringent current building standards but rather for structural deficiencies that through the course of time have proven to be the cause of structural failures.
The evaluation begins with a checklist that gets completed for the particular type of building being evaluated. This ascertains if known structural deficiencies for the type of structure in question are present in the subject structure. If none are encountered, the structure is deemed to be adequate by the provisions of this national standard. No further evaluation or strengthening is required.
If the structure has components on the checklist that are deemed to be initially deficient, there are two possible courses of action: perform a more refined evaluation that may show that the component with the perceived deficiency is actually adequate, or do no further evaluation and strengthen the component.
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