Multiple-Criteria Decision-Making in the Design of Innovative Lock Walls for Barge Impact; Phase 1

Abstract : This report summarizes the research efforts performed to date in support of the U.S. Army Corps of Engineers (USACE) to make design decisions pertaining to the innovative construction of navigation locks to minimize construction costs. This research project consists of two phases: Phase 1, which culminates with this report, investigated the use of multiple-criteria decision-making in the design process of lock approach walls to consider barge impact and earthquake loads. Phase 2 involves the development a computer programming tool that uses the previously developed methodology and its application to case studies for innovative lock approach walls. After reviewing the available literature, featuring various USACE engineering manuals and papers on the methodology of multiple- criteria decision-making, the research efforts were focused on hazard and reliability analysis due to multiple failure modes. Realizing that navigation structures are vulnerable to barge impacts, earthquakes, operational errors, and extreme events such as bombings, a conceptual framework was initially developed for analyzing the consequences of barge impacts and earthquakes. The reliability was also evaluated as a function of time for a "generic" navigation lock due to the joint potential for both collision and earthquake. A mathematical scheme was developed to evaluate the mean time to failure of a lock structure due to multiple causes. Another primary thrust of this research project focused on tradeoff analysis. The objectives of multiple-criteria decision-making are to minimize both construction cost and repair damage caused by incipient failures. This report did not directly consider design and construction costs. Rather, the focus was on the robustness of a navigation structure as measured by the designed maximum impact force and the designed maximum ground motion that the structure could experience. The impacts of partial or complete failures on different designs were evaluated.