Flexural Behavior of Staggered Steel Sheet Pile Wall with Mechanical and Welded Joints

Abstract

This study evaluates the performance of staggered steel sheet piles with mechanical and welded joints designed for efficient pile installation in environments with headroom restrictions, such as under road bridges. Through full-scale flexural tests and frame analysis, the author compares the structural performance of these piles when assembled using mechanical and welded joints, with a particular focus on the impact of staggered assembly configurations. A total of eight bending tests were conducted: single sheet piles with spliced joints (both mechanical and welded) in both directions, and walls consisting of four interlocked sheet piles, including both standard and jointed sheet piles. Walls with spliced joints showed intermediate performance between the single sheet piles tested in both directions. The test reveals that mechanical joints cause additional deflection, resulting from the standard pile deflection combined with rotational displacement at the joints. The frame analysis to simulate joints with rotational springs and interlocks with rigid connections reproduced the test results well. It showed that large loads in the direction of deflection are transferred via interlocks to the neighbouring sheet pile to prevent bending moments greater than the plastic bending moment from acting on the joint. These findings provide critical insights into the design and installation of steel sheet piles, offering potential for improved construction practices in constrained settings.