Comparison of Flexural Stiffness between Hat-type and U-type Steel Sheet Pile Retaining Walls in a Field Test in Singapore

The use of the Hat-type steel sheet pile can potentially improve the performance of earth retaining walls because of two of its features: its wide width and location of interlocks. It can reduce the piling time and number of piles required for walls because of its 900-mm width, which is the widest among the hot-rolled monopiles in the world. Furthermore, Hat-type piles can achieve full-shear force transmission at the interlocks because their connections are located at the outer edge of the wall. This study focuses on the second feature, i.e., the interlock shear force transmission. The lateral load and excavation tests were performed to compare and verify the difference in the interlock behavior between U-type and Hat-type sheet piles. As the result, in contract to the reduction of shear force transmission of the U-pile wall, the Hat-pile wall exhibited high flexural stiffness because the interlocks achieved the full-shear transmission mode.