Extreme values of thermal loading parameters in concrete bridges

Abstract

The present paper addresses the question of developing design criteria for thermal effects in concrete bridges. The objective is to determine extreme temperature effects having specified return periods. The parameters of the local meteorological regime which critically affect the extreme thermal effects are identified. Their variation in time is analyzed and related to the thermal loading parameters in a concrete bridge. These include average temperature, temperature difference between sections, linear temperature differential, and residual temperature fields. The analysis of the extreme values of these parameters is described in detail.The reduction of data, the model development, and the statistical analysis are clarified by the application to the Bow River light rail transit bridge in Calgary, Alberta. Temperature profiles in several sections of this structure are being measured on an hourly basis. The findings of this study show certain shortcomings of the temperature effects design criteria currently included in the Canadian bridge design codes. Key words: extreme values, design temperature, thermal loading, thermal gradients, temperature measurements, concrete box girder bridges.