SummaryThis paper presents a new heterogeneous multiscale modeling method for porous media flows. Physics at the global level is governed by one set of PDEs, while features in the solution that are beyond the resolution capacity of the global model are accounted for by the next refined set of governing equations. In this method, the global or coarse model is given by the Darcy equation, while the local or refined model is given by the Darcy–Stokes equation. Concurrent domain decomposition where global and local models are applied to adjacent subdomains, as well as overlapping domain decomposition where global and local models coexist on overlapping domains, is considered. An interface operator is developed for the case where global and local models commute along the common interface. For the overlapping decomposition, a residual‐based coupling technique is developed that consistently facilitates bottom‐up embedding of scale effects from the local Darcy–Stokes model into the global Darcy model. Numerical results are presented for nonoverlapping and overlapping domain decompositions for various benchmark problems. Computed results show that the hierarchically coupled models accurately account for the heterogeneity of the medium and efficiently incorporate local features into the global response. Copyright © 2014 John Wiley & Sons, Ltd.

No abstract

The U.S. Army Corps of Engineers (USACE) maintains a lessons-learned goal for all major projects to capture knowledge gained. The focus of the formal lessons-learned process is to share knowledge and experience nationwide improving USACE contracting methodologies, reducing overall costs, and improving designs. This continuous improvement can be seen in the evolution of USACE barrier wall construction designs and contracting methods. From the first Wolf Creek Dam barrier wall installed in the 1970s to the more recent Bolivar and East Branch Dam barrier wall projects, documentation and sharing of lessons learned in areas such as grouting, data management, and quality assurance procedures have increased the efficiency and effectiveness of barrier wall designs, monitoring, and contract specifications. Contractual philosophy, use of pre-grouting treatment, verification methods, and data management processes have all changed due to lessons learned and have enabled the USACE to improve the overall end product of barrier wall projects.

No abstract