Effect of Proximity of Sheet Pile Walls on the Apparent Capacity of Driven Displacement Piles, Phase 2

US Transportation Collection2019PDFTech ReportChung, Jae HKrauthammer, TedMishra, NikhilTaylor, AdamUniversity of Florida (Gainesville). Engineering School of Sustainable Infrastructure and EnvironmentFlorida. Department of Transportation. Research CenterFlorida. Department of Transportation. Research CenterUnited StatesBearing capacityCofferdamsDesign chartsDiscrete element methodFinite element methodGranular soilsResistance (Mechanics)Sheet pile wallsBDV31 TWO 977-102This Phase 2 report continues research investigating the effects that installation and removal of sheet pile walls (SPWs) have on driven piles founded in granular soils. The method of analysis employed in Task 5 of Phase 1 of this project is extended to model systems involving a driven pile in proximity to two SPWs forming the corner of a closed rectangular cofferdam. Numerical simulations are presented which employ a combined Finite Element Method-Discrete Element Method (FEM-DEM) procedure which explicitly captures the mechanical behavior of the pile-soil-SPW system. Three relevant physical scenarios are studied, with a top-down load test following: (1) Pile driving into sand; (2) SPWs installation one at a time followed by pile driving into sand; and, (3) SPW installation, pile driving, and subsequent SPW removal one at a time in reverse sequence. The Davisson and ultimate capacities of the driven pile are therefore assessed in the presence of a driven SPW cofferdam, as well as in a soil from which the SPW structure has been recently removed. The response of the pile is shown to be dependent on geometrical parameters of the system; a parametric study is therefore performed with respect to the ratio of SPW cofferdam embedment depth versus the embedment depth of the pile. The components of total resistance are studied with respect to the pile\u2019s tip resistance and side friction; the relationships of these components to the presence or removal of the SPWs at various embedment depths are recorded. The results are condensed into a series of simple design charts which quantify the effects of the SPW cofferdam in scenarios 2 and 3 on the bearing capacities of the pile. Recommendations for the use of these graphical tools are presented for the easy quantification of these influences for the engineer facing relevant design decisions.140