Joint Analysis of Structural Flexibility Uncertainty and Deflection Serviceability Limit State Reliability Using the Active Excitation Method

Flexibility is a key parameter that reflects the service status of an engineering structure, which includes safety and applicability. Rapid structural safety evaluation based on active excitation tests for flexibility has gradually matured, but studies on structural applicability evaluation are scarce. In this paper, a framework for existing bridge applicability evaluation based on forced-vibration tests is established by the joint analysis of structural flexibility uncertainty and deflection serviceability limit state reliability, which avoids the need for complex static loading or accurate finite-element modeling. The analytical expression of structural flexibility uncertainty is first derived based on the combination of the trust region method and the first-order perturbation theory. On this basis, the reliability analysis of the structural deflection serviceability limit state is conducted by constructing the structure performance function. Case studies using numerical simulation data from a simply supported beam and experimental data from a continuous girder bridge and a T-shaped rigid frame bridge are considered to verify the accuracy and validity of the proposed method.