Title: Thermal Movements of Concrete Bridges: Field Measurements and Methods of Prediction

Author(s): Mary Emerson

Publication: Symposium Paper

Volume: 70

Issue:

Appears on pages(s): 77-102

Keywords: bridge bearings; bridge decks; bridges (structures); control joints; field tests; measurement; research; structural design; temperature; thermal expansion.

DOI: 10.14359/17403

Date: 1/1/1981

Abstract:
One of the research programmes in progress at the Transport and Road Research Laboratory is to investigate the thermal behaviour of concrete bridges in the United Kingdom. Part of the work involved the measurement of the longitudinal movement of bridge decks caused by changes in temperature. Some of these measurements of movement were made continuously for periods of up to five years at any one site and the types of bridge instrumented include concrete box (single and multi-cell), concrete beam and slab and solid concrete deck. A brief description of the instrumentation is given and the results discussed include measured values of daily and annual ranges of movement, the seasonal effect on the measured movement of shrinkage of the concrete and short and long term values of the coefficient of thermal expansion of the deck. It is also shown how both daily and annual maximum values of movement may be predicted from a knowledge of the temperature of the deck, which, in turn, may be derived from the variation in the shade air temperature. This knowledge enables the bearings and expansion joints to be set at their correct positions within the design range of thermal movement of the deck.