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With the increase of marine activities in the Arctic area, the demand for reliable design of marine structures is growing. Numerous publications can be found regarding simulations of ice action on structures using cohesive element models of the ice. However, previous studies have rarely discussed the influence of structural form, that is, the form of ice-structure interaction interface, on the ice load. Thus, a more comprehensive understanding of the ice load on structures with different interface geometries needs to be explored. In the present paper, three-dimensional finite element models with the cohesive element method are developed to investigate the ice load on different structures. The numerical results are validated based on in-situ testing data and the results of the previous numerical model. Parametric studies considering structure widths, inclination angles, ice velocity as well as structure roughness are conducted to explore the horizontal force and failure process of the ice sheet. The process of ice-structure interaction and ice loads on different structural forms were discussed and simplified diagrams of ice load distribution on the interface were developed. [ABSTRACT FROM AUTHOR]

Abstract Sheet pile walls providing lateral earth support are widely employed as excavation supporting systems for cutting slopes along the high-speed railway. In this study, a validated three-dimensional finite element (FE) model based on field measurements was used to explore lateral earth pressure distribution on sheet pile walls, aiming to provide guidelines and recommendations for design of the sheet pile walls. To this end, the influence of pile length, sheet's location, pile's stiffness, and soil properties on the pile performance were investigated. The results showed that the optimum pile length was about 14 m for the sheet pile walls at a China high-speed railway. The sheet's location could affect the formation of soil arching and the mechanism of earth pressure distribution. The moment of inertia of sheet pile walls was found to be effective in controlling pile displacement and earth pressure, compared to Young's modulus of the pile. Variations of soil parameters led to negligible changes in the earth pressure distribution. Furthermore, a proposed simplified straight-line form for earth pressure diagram based upon the FE analysis was developed. Compared with traditional earth pressure methods, the proposed diagram considers the sheet effect. Overall, the conducted study provided useful help toward the process of safer design and more economical sheet pile walls. Highlights • A calibrated 3D numerical modeling was used to investigate lateral earth pressure on sheet pile walls. • Several key parameters affecting earth pressure distribution was quantified and discussed. • A proposed straight-line form for earth pressures that considers the effect of sheet was developed. [ABSTRACT FROM AUTHOR]

The geosynthetic-encased stone column (ESC) strategy has been extensively used for improving soft soils. However, no studies have been conducted to assess the use of ESCs to mitigate sand strata. In this study, three-dimensional finite element (FE) analyses were conducted to explore the mitigation of mildly sloped saturated sand strata using ESC approaches. We investigated the encasement effect in ESC remediation and the effect of the following important design parameters in reducing lateral ground deformation: the thickness, the tensile stiffness, and the permeability of the geosynthetic; the ESC diameter; and the distributed load at the stone column (SC) surface. The results showed that the ESC remediation reduced more lateral deformation, compared to the SC approach. The ground stiffening was also dramatically enhanced as the stiffness and thickness of the geosynthetic and the ESC diameter were increased, but the encased efficiency gradually decreased. The lateral ground displacement began to decrease significantly when the permeability of the geosynthetic exceeded 0.1 m/s. The larger surface load did not prevent soil liquefaction, but it produced significantly less displacements and virtually no permanent deformation. [ABSTRACT FROM AUTHOR]

In order to investigate the liquefied soil pressure inposed on an individual pile of pile group, a centrifugal shake table test on a pile-supported wharf on the sloping saturated sand stratum has been designed and implemented in this study. Final test results, including processing results of free-field soil responses as well as lateral displacements at the deck, are presented and discussed in detail. Analysis of pile bending moments of pile group shows that seaside pile bottom can come under more bending moment in contrast to landside piles, and the bending moment seems greater at pile top and bottom. A simplified finite element model has been constructed for an accurate analysis of liquefied soil pressure arising from lateral soil flow, where triangular soil pressure and uniform soil pressure need to be calibrated according to the measured monotonic bending moment of piles. Furthermore, comparisons with the current distribution law were made using the experimental outcomes. Finally, for investigating the effect of pile connection point rotational stiffness, parametric studies were carried out. • Seismic behavior of the soil and pile-supported wharf in liquefiable sloping stratum is presented and analyzed. • A finite element modeling is developed to investigate liquefied flow soil pressure scenarios on the pile group. • Two force-based design guidelines from JRA and JSWA are further calibrated. • Influences of key factors on the behavior of pile-supported wharf are examined. [ABSTRACT FROM AUTHOR]