| A methodology to evaluate structural reliability of existing bridge structures using advanced reliability FORM/SORM (First Order Reliability Method/Second Order Reliability Method) methods is presented. The methodology is applied to evaluate the structural reliability of bridge steel members subject to compression, tension, shear and bending. The steel truss members, floor beam and stringer of a typical span located on the Jacques-Cartier Bridge in Montreal are evaluated using this methodology. Data for the evaluation was obtained from a comprehensive inspection and sampling program on the bridge involving tests on 74 steel coupons. The results of the evaluation are then compared to the results of the evaluation using the load and resistance factors method and the mean load method outlined in the draft version of the CHBDC, 1998, (Canadian Highway Bridge Design Code).; In this application, the advanced reliability analysis indicates that the estimation of the reliability of bridge members, in their current condition, using the loads and resistance factors method specified in the code may be too conservative. This situation was encountered in the case of the floor beams of the analysed span, when the failure mode considered was shear. The advanced reliability analysis indicates also in this application, that the evaluation of the reliability of bridge members, using the mean load method specified in the code may not be conservative. This situation was encountered in the case of the truss members of the analysed span, when the failure mode considered was compression.; The evaluation of bridge structures using advanced structural reliability methods can be used to obtain more accurate estimates of their reliability. This information can be used to develop better, monitoring, inspection, maintenance, and rehabilitation strategies for bridge members. |
