Flexural Behavior of a Fully Prefabricated Lightweight UHPC Bent Cap

Abstract

A novel lightweight prestressed ultrahigh-performance concrete (UHPC) bent cap is proposed, consisting of a large cantilevered thin-walled box girder weighing approximately 40% less than normal concrete bent caps. The proposed bent cap commendably surmounts the disadvantages of normal concrete bent caps, such as poor durability, heavy self-weight, and complicated construction. The flexural behavior of the UHPC bent cap was investigated through an experimental study with a large-scale specimen. Experimental results for deflection, strain, crack pattern, failure mode, and ultimate flexural capacity were obtained. This study focused on the cracking behavior and flexural performance of the bent cap. Calculation methods for flexural capacity and cracking moment were investigated, and the calculation results were in good agreement with the test data. This research found that the proposed novel lightweight UHPC bent cap exhibits excellent flexural behavior and satisfies practical engineering requirements. This study can be used as a reference in the design and application of UHPC bent caps.