Research on Fatigue Performance of Segmental Precast Concrete T‐section Beams

Abstract In order to study the fatigue performance of segmental precast concrete T‐section Beams, six test beams were designed and manufactured with the construction technology (integral cast‐in‐place and segmental precast) and key teeth type (large key‐joint and double key‐joint) as the control factors. Through the two‐point loading test, the ultimate bearing capacity of the test beam is obtained, which provides a basis for the upper limit and lower limit of the fatigue test load. After that, fatigue loads were carried out on the three test beams manufactured in the same batch as the test beams in the static load test, and the concrete compressive strain, steel strand strain, mid‐span deflection, and fatigue damage mode near the joints during the fatigue test were obtained, and the processing technology was discussed. and teeth type on the fatigue performance of T‐section Beams. The test results show that the growth of concrete compressive strain, steel strand tensile strain, and mid‐span deflection near the joints of segmental prefabricated T‐section Beam conforms to the three‐stage growth law. Under the same fatigue load, the fatigue performance of the T‐section Beam processed by the integral cast‐in‐place process is better than that of the T‐section Beam processed by the segmental prefabrication process, and the fatigue performance of the segmental prefabricated assembled beam with double key‐joint is better than that of the prefabricated assembled beams with large key‐joint. Based on the static loading results after different cycles in the fatigue test, the stiffness degradation laws of segmental prefabricated concrete beams with different teeth types are obtained, and the stiffness degradation of the double‐key‐teeth segmental beam is slower than that of the large‐key‐teeth segmental beam.