Abstract:

The timedependent reliability problem of the concrete structure in northern sea regions of China was discussed. The degradation behaviors of the mechanical properties such as Young’s modulus, compressive strength and tensile strength of the concrete structure after the freezethaw cycles were revealed through a great deal of inlab freezethaw tests. The mechanical parameter degradation of the concrete pier with the freezethaw cycle number were obtained, and the strengthtime degradation laws were abtained. A timedependent reliability calculation method of the concrete structure in the freezethaw environment was proposed. The lower concrete structure of the pier of Cangkou searoute of Tsingdao Bay bridge were analyzed numerically by the finite element reliability theory and the proposed method, and the reliability index variation with time was obtained, providing a reference for the engineering maintenance decision making of the pier.

Key words: engineering mechanics, Tsingtao Bay bridge, freezethaw, mechanical property, timedependent reliability