Architecture

Spudcans are conical footings used as foundations for offshore platforms. Installation in soft marine soil forces them deeply into the seabed, inducing gross motion and severe plastic deformation in the soil. A pure Lagrangian-based finite element approach for modeling spudcan installation and extraction can be very difficult. Because the mesh moves with the material, ele-ment distortion typically accompanies severe deformation and convergence difficulties follow.

On August 1, 2007, the I-35W highway bridge over the Mississippi river in Minneapolis, MN collapsed. The sub-sequent National Transportation Safety Board (NTSB) investigation identified the U10W truss node as a likely initiation site for the failure. (Bridge main truss nodes were numbered from the south starting at 0. U indicates a node along the upper chord, and L indicates a node along the lower chord. E and W indicate a node on the east or west truss) [1, 2, 3].

Assessing the strength of soil slopes and investigating the means for increasing their safety against failure are cru-cial in construction projects involving large soil masses. Slope stability analyses have traditionally been performed using a limit state approach. However, any presence of reinforcement or local heterogeneity necessitates the use of numerical techniques such as finite element analysis. Abaqus/Standard can be used for modeling reinforced soils and can thus help geotechnical engineers in deter-mining optimal reinforcement sizes and placement con-figurations.

Pullout resistance of driven foundation piles often in-creases with time in a process known as pile “setup.” The consolidation of the surrounding soil after the pile is driven plays a dominant role in the setup process. Finite element modeling of pile setup can help in obtaining reli-able estimates of the increase in pile resistance, which would allow for reductions in pile lengths, pile sections, or sizes of the pile driving equipment.

Finite element modeling of prestressed concrete contain-ment vessels (PCCVs, Ref. 1) for nuclear power plants poses special challenges. PCCVs, which are heavily rein-forced structures, are designed to deform beyond the cracking limits of the concrete. Abaqus has been used extensively for analyzing such structures in the nuclear utility industry (Ref. 2) and can be used to assess and improve the performance of these and other similar rein-forced concrete structures.

Construction of earthen dams entails sequential place-ment and compaction of soil layers and the subsequent fill-up of the embanked reservoir. In the design of earthen dams, two potentially critical events must be considered: the rapid emptying (or drawdown) of the reservoir and the dynamic loading of an earthquake. The possibility of dam failure in these situations depends on the respective build-up and dissipation of the fluid pore pressure in the soil.

Oblique elastic impact of spheres and the related case for cylinders have been studied cases for many years in simulations of systems with loose supports, such as heat exchanger tube-support interaction, as well as granular flows and robotic task modeling. The problem is a relative simple one in the class of transient frictional contact problems in that the stresses away from the contact zone are typically neglected. The available continuum model solutions from literature show some very interesting features.

The fire resistance of steel framed multi story buildings and their ability to withstand

exposure to fully developed fire conditions without the need for all structural members to be

Due to the limitation of computer capacity and the soften of the material constitution, the nonlinear dynamic earthquake analyses of skyscrapers are not practical in engineer’s desktop, and even in the research area they are still open problems. Utilizing ABAQUS’s unique combination of implicit and explicit technologies and capable of solving large problem efficiently, the author solves the problem elegantly and practically. In the analysis model, all members and shear-walls are modeled by plastic zone model, and large deflection effects are taking into account.