AbstractJointless bridges are typically designed with flexible foundations that include one row of piles. Because the main criterion limiting the length of jointless bridges is the lateral displacement capacity of their supporting piles, longer jointless bridges can be built by increasing that capacity. Preliminary analysis in this study revealed that the lateral stiffness of a pile decreases drastically when a pinned connection at the top of the pile is provided. As a result, the maximum moment developed in the pile decreases and its lateral displacement capacity increases. This paper presents a flexible pile-head to pile-cap connection detail. An experimental study was carried out to comprehend the performance of the proposed detail, and the results of the experimentation were used in conjunction with numerical and analytical studies to develop design provisions.