Evaluation of actual creep length under heading up structures aprons

Abstract

In this paper a 2D finite element model (SEEP 2D) is implemented to study the actual head loss along the sheet piles fixed at the ends of an apron of a heading up structure. Different scenarios for the thickness of the pervious layer under the apron, the length of the apron and the depths of the upstream and downstream sheet piles are studied.Results show that the assumption that outer and inner faces of the sheet piles have the same weight for estimating the creep length while designing aprons of hydraulic structures is a weak one. Design equations for the actual head loss along the outer and inner faces for both the upstream and downstream sheet piles are driven. These equations can be used as a tool in the practical design for aprons of heading up structures formed on pervious soil and provided with upstream and downstream sheet piles at its ends. Keywords: SEEP2D, Seepage, Heading-up structures, Sheet piles, Creep length