Vol.7, No1, 2007, pp. 29-36
UDC 624.012.3.042:519.245

Abstract

Damage process initiation and propagation in concrete structures is a time dependent phenomenon with the negative implication to the structure load bearing capacity, decreasing its overall resistance and as a final consequence, decreasing degree of structural safety and reliability. Previous deterministic procedure of concrete structural integrity assessment is expensive and conservative, leading to a rather subjective decision and to conclusions without proper answers about the true structural safety degree, and thus leading to implementation of non-optimal reparation procedures. In the paper, the probabilistic approach is proposed which, on the basis of previous analysis of critical structural elements and virtual structural failure mechanism, and accepted corresponding marginal state, determines the probability of reaching the marginal state and in conjunction with expected negative consequences, assesses the degree of risk that the structure is exposed to. As an example, the procedure is applied in integrity assessment of the pre-stressed concrete highway bridge. The bridge was heavily damaged during NATO bombing of Yugoslavia and an urgent decision on optimal measures for bridge reparation was requested. The Monte-Carlo method was applied for proposed marginal state of bridge structure, and the degree of risk is calculated and the right decision was made.

Keywords: concrete structure, risk, integrity, damage, Monte Carlo method