This paper describes the design and construction processes associated with site improvement and the pavement system. Traffic demand on truck and passing lanes was evaluated based on estimated throughput including the effects of container type, size, block size and dwell time. The design followed the 1993 AASHTO Guidelines. Load equivalency factors were used to account for non-linearity of axle load effects from different yard equipment. Finite element modeling was used to determine shortterm load demands on pavement elements to account for complex loading conditions.

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This paper describes the planning and design of a major expansion at the Port of Cristobal in Panama. The port consists of a series of finger piers and slips connected to a rubble-mound breakwater. The expansion project will reconfigure the existing site by filling the slips and incorporating the existing 100-year-old finger piers into a new marginal wharf and container yard. Major features of the project include 9.9 hectares (24 acres) of pile-supported container yard and a new 420-meter-long (1,378 feet) super post-Panamax wharf.The ambitious three-year development schedule -combined with new construction at a busy, existing port -posed problems solved by partitioning the site and developing a program that allowed a sequenced handover of the works to accommodate the operator's needs.Integrating existing facilities and features into the new construction and unknown subsurface conditions were significant challenges. These challenges included rehabilitation of the existing pier structures, very deep soft soils requiring pile lengths up to 52 meters (171 feet) in length, seismic design of the large heavily loaded pilesupported deck, and accommodation of utilities within the deck structure. The solutions included varied pile types ranging from composite prestressed concrete piles with steel pipe pile extensions to large-diameter steel pipe piles.

In the Arctic, thermal erosion results from ground thawing produced by heat transfer when water is flowing upon the frozen ground. A mathematical model has been proposed to determine the efficiency of the process and the rate of thermal erosion. Considering a constant heat-transfer coefficient, the resulting thermal flux at the groundsurface produces ground thaw, and the unfrozen sediments can be removed by the water flow. A particular case of an ablation model consists of an immediate removing of sediments by a strong flow and by the action of gravity. An experimental hydraulic device was built to test the authors' theoretical ablation model, describing a fluvial thermalerosionprocess. The effect of different parameters (Reynolds number, water temperature, ground-ice temperature) on the rate of thermal erosion for samples of frozen sand was investigated. Results from the experiments are in agreement with theoretical estimates using the mathematical model. Moreover, this study shows a hierarchy of parameters in terms of efficiency of the fluvial thermal-erosion process.A discussion of the possible effects of the contaminants on the erosion rate leads the authors to propose two kinds of experiments: a contaminated frozen sample eroded by a water flow, varying in this case the thermophysical properties of the sample (density, specific heat capacity, a latent heat, and change of phase), and an experiment consisting of erosion of a frozen sample by contaminated flow. This second case is also complex due to many mechanical, hydrodynamic and thermal interactions at the ground surface. This paper reports results of thermal erosionfrom experiments with icesaturated sand. A pure ice sample is used to determine the heat-transfer coefficient.