Test and Research of Long-Term Stress Variation of High-Pier & Long-Span Continuous Rigid-Frame Bridge

Abstract

Pre-stressed concrete continuous rigid frame bridges have been widely used for modern long-span bridges due to its advantages, such as comfortable for travelling, easy to be constructed and maintained etc. However, cracks and excessive mid-span sag of box girders generally exist in many built bridges of this kind during service, and because of its large size and the complex natural environment, it is particularly important to study the long-term performance based on the long-term field measurements. In this paper, a high-pier & long-span pre-stressed concrete continuous rigid-frame bridges, with five-spans (106m+3×200m+106m), was taken as the research object, by pre-embedding strain sensors in mid-span sections and root sections on box girders, field-tests for stress variation were conducted in extreme weather conditions (ie, the hottest and coldest in one year) after its completion in two years, providing tested data for studying long-term performance of bridges similar to the same kind.