Thermal design criteria for deep prestressed concrete girders based on data from Confederation Bridge

Abstract

The evaluation of temperature data recorded on the world's longest bridge built over ice-covered water is presented. The data in question are the hourly recorded temperatures in three girder sections with variable geometry and ambient temperature, solar radiation, and wind speed measured on site from 1998 to 2000. The data were first carefully screened, and problematic records were identified and repaired. The temperatures were then spatially reduced to a set of thermal variables including average, differential, and residual temperatures. Extreme value analysis was performed to obtain 100 year return thermal loads. The results are compared with the provisions in the Canadian highway bridge design code (CAN/CSA-S6-00) and the original design temperatures for the bridge. Temperature distributions for maximum positive vertical differential temperatures during the recording period are plotted for the three girder sections. The observed unrestrained curvatures and nonlinear stresses are compared with those estimated by the Priestley model. Modifications are found to be necessary for extremely deep cross sections.Key words: concrete bridge, thermal response, statistical evaluation, average temperature, differential temperature, curvature, stress.

Temperature Distributions and Variations in Concrete Box-Girder Bridges: Experimental and Finite Element Parametric Studies

“…Along with the thermal properties of concrete, the wind speed, the bridge orientation and the geometric configuration are principal parameters. Several studies on the effect of wind speed (Elbadry and Ghali 1983;Wang et al 2010), bridge orientation (Dilger et al 1983;Elbadry and Ghali 1983;Moorty and Roeder 1992;Fernando and Mendes 1993) and geometric configuration (Dilger et al 1983;Elbadry and Ghali 1983;Li et al 2004;Mirambell and Aguado 1990) are found in the current literature, while detailed parametric studies on the influence of thermal properties on temperature variations and distributions in concrete Box-Girder (BG) bridges are rare. Based on the current literature survey, it can be stated that a parametric study on concrete BG is required.…”

Measuring and modelling the thermal performance of the Tamar Suspension Bridge using a wireless sensor network

“…Larsson & Karoumi (2011) developed a finite element model to predict internal temperature distributions based on climatic information, which they validated with measured temperature records from the New Svinesund Bridge (concrete arch bridge, 704 m total span) between Sweden and Norway. Long-term monitoring projects, such as the ones carried out on the Calgary LRT Bow River bridge (prestressed concrete) (Maes, Dilger, & Ballyk, 1992) and the Confederation Bridge (prestressed concrete, 45 x 250 m main spans) (Cheung et al, 1997;Li, Maes, & Dilger, 2004) in Canada, have been instrumental in improving the understanding of temperature distributions and actions on concrete bridges.…”

A study of thermal response of concrete towers employing linear regression

“…Thermal gradients of concrete bridges were analyzed employing in-depth concrete temperatures and ambient temperatures [5], [6], thermal loadings have been included in finite element analysis [7], [8], effects of ambient temperature on the modal properties of bridges were reviewed [9]- [14] and recently, anomaly detection algorithms based on structure responses to temperature are being suggested [15]- [19]. [20] Although it has been shown that levels of stress caused by temperature far exceed any stress caused by recorded traffic [21]- [23], studying the thermal response of a structure and documenting the normal behavior of a structure due to environmental changes can be challenging; solar radiation and heat exchange of different parts of a structure with the surrounding environment are correlated with the orientation of the structure and hence the temperature profile is nonuniform and nonlinear [24], [25].…”