Allen C. Estes

Project-Based Independent Study Capstone Course

Ronald W. Welch — Wed, 12 Aug 2009 10:25:23 PDT

This paper describes a unique project-based course used successful by the ABET-Accredited Civil Engineering Program at the United States Military Academy (USMA) to greatly enhance the academic program. The three general project classifications available within this senior course are service-based (i.e., USMA, the Army, local community, etc.), competition-based (i.e., steel bridge, concrete canoe, timber bridge, Big Beam), and research-based. The exceptional student work provided at little to no cost to the client has opened up a ground swell of service and research projects now constantly offered to the program coordinator by prospective clients. We believe these independent study projects are successful due to our students being prepared through open-ended design in nearly every course we offer and through some initial project-based learning in earlier courses. The mix of these open-ended projects usually ensures that each student can list a minimum of 3.5 project choices that meet their individual needs for a challenging, yet rewarding academic experience. Approximately 90.98 percent of the senior CE majors each year choose to work on one of these open-ended projects. With 45 to 60 CE majors graduating each year, it is easy to understand that one faculty member cannot advise the required 15.20 projects each spring. So many, if not all, of the CE program's 17 faculty must buy-in to the project-based senior program from the onset. It will be shown through student assessment that this form of experience not only challenges, but also motivates the students like no other aspect of their academic experience. The students are providing a solution to a real world problem for a real client. The assessment will show that the students find project-based learning demanding, but enjoyable and worthwhile because it forces them to push the boundaries of their knowledge through initiative, self-study, perseverance, and creativity.

Using Condition Index Inspection Results to Update the Reliability of Miter Gates for Navigation Locks

Allen C. Estes — Wed, 12 Aug 2009 10:25:08 PDT

In an effort to ensure public safety, many civil engineering structures undergo various inspections to assess their condition or performance. Comprehensive procedures for using routine inspection data to update reliability assessments have not been developed. This paper illustrates how the Condition Index inspection data from a specific miter gate on a Corps of Engineers navigation lock can be modified and used for this purpose.

Two Alternative System Reliability Approaches to the Serviceability Condition Assessment of Spillway Gate Systems on Dams

Allen C. Estes — Wed, 12 Aug 2009 10:24:53 PDT

Two competing methods were introduced for analyzing the condition of a structural system. The results produced by both were very different. In the weighted average approach, the system condition index will always be somewhere between the condition of the best and worst component in the system. In the traditional reliability approach, the condition index will always be lower than the condition of the worst member in a series system and higher than the condition of the best member in a parallel system. A traditional reliability approach works extremely well for a strength-based system where the importance factors of the components are relatively equal and the consequences of failure are typically catastrophic. In a serviceability context where some failures are more serious than others and some components are clearly more important than others, the information provided is less useful. The extreme values obtained in the traditional approach exaggerate the condition of the structure. A condition index of over 100 for the parallel structure would probably ensure it does not get replaced until every portion of the system is significantly deteriorated. In a multi-tiered series system, such as the spillway gate system presented here, the condition index would be so low that it would appear that every structure was in dire need of replacement. The condition of the worst element in the system, no matter how minor, controls the maintenance decision. If the goal is to use the overall condition of a structure to prioritize and optimize maintenance funding, the weighted average approach seems to provide better decision making information. By combining the condition of components with their importance to the overall system, it is easier to make a distinction between competing priorities. While series and parallel systems are treated in the same manner, a distinction could be made in the assignment of importance factors where a redundant system might receive a lower importance factor.

Program Assessment: A Structured, Systematic, Sustainable Example for Civil Engineers

Allen C. Estes — Tue, 17 Feb 2009 09:04:20 PST

As the outcomes-based accreditation process continues to evolve since its implementation six years ago, the standards for program assessment and continuous improvement are progressively being raised and many schools struggle with what is required. This paper offers an example of a structured, systematic, sustainable assessment program implemented by the civil engineering program at the United States Military Academy. The process is compatible with the university assessment process and has eight years of documented results. The assessment includes fast loop and slow loop cycles that accomplish very different things. Other features include standardized course assessments, embedded indicators, performance measures for all outcomes and objectives, advisory boards, feedback from all constituencies, faculty involvement, and closing of the feedback loop.

Updating Reliability of Steel Miter Gates on Locks and Dams Using Visual Inspection Results

Allen C. Estes — Wed, 13 Aug 2008 16:45:41 PDT

As both reliability analyses and systematic inspection programs for the world's infrastructure gain increased usage and prominence, it becomes more important to use the information from routine visual inspections to update lifetime reliability assessments and resulting life-cycle inspection/repair strategies. The Army Corps of Engineers currently uses reliability analyses to economically justify the major rehabilitation of navigation structures. This paper illustrates how the Condition Index visual inspections for locks and dams can be modified and used to update the reliability analysis of a steel miter gate. The miter gates on two existing locks and dams along the Mississippi River are used as examples for corrosion and fatigue deterioration. The approach used is applicable to any structure where the inspection condition states are quantitative and a model exists to relate visual inspection results to the actual deterioration state of the structure.

Load Rating versus Reliability Analysis

Allen C. Estes — Wed, 13 Aug 2008 16:45:38 PDT

The most common approach to assess the safety of a bridge is load rating. However, this approach cannot quantify the bridge safety in probabilistic terms or fully quantify the structural risk to the bridge. Reliability methods have become an increasingly popular and gradually accepted approach to assess the safety of structures. These methods account for the randomness and correlation of all relevant variables and failure modes in the analysis. This study performs both a load rating analysis and a reliability analysis on the same highway bridge, compares the results, and discusses the strengths and limitations of each approach.

Updating Bridge Reliability Based on Bridge Management Systems Visual Inspection Results

Allen C. Estes — Wed, 13 Aug 2008 16:39:52 PDT

Bridge management systems have become increasingly sophisticated over the past decade and provide valuable information about the structural condition of all bridges in the national database. At the same time, reliability methods have gained increasing prominence and are used to forecast life-cycle performance over many decades of structural life. Such reliability analyses need to be updated based on the results of inspections. Specifically targeted nondestructive evaluations are the preferred solution, but are not always available for every bridge. This paper examines how the visual inspection data provided from bridge management systems already in place can be used to update the reliability of a bridge. The limitations and necessary modifications to current practice are discussed. The superstructure of a Colorado highway bridge deteriorating due to corrosion is used as an example.

Repair Optimization of Highway Bridges Using System Reliability Approach

Allen C. Estes — Wed, 13 Aug 2008 16:39:32 PDT

As reliability based methods gain increased acceptance, there is greater opportunity to use scarce resources more efficiently while maintaining a prescribed level of reliability of a structure throughout its service life. The goal is to provide management decisions that will balance lifetime system reliability and expected life-cycle cost in an optimal manner. This study proposes a system reliability approach for optimizing the lifetime repair strategy for highway bridges. The approach is demonstrated using an existing Colorado State highway bridge. The bridge is modeled as a series-parallel combination of failure modes, and the reliability of the overall bridge system is computed using time-dependent deterioration models and live load models. Based on an established repair criterion, available repair options, repair costs, and updating, the optimum lifetime repair strategy is developed. The sensitivity of the optimum strategy to changes in various problem parameters including the prescribed service life, system failure criterion, and net discount rate is studied. Finally, the conclusions reveal that the proposed approach demonstrates real potential for practical applications, needs frequent updates through inspection, and requires considerable research effort to develop accurate input data.

Teaching Lessons Learned: Shock and Awe in the Civil Engineering Classroom

Allen C. Estes — Wed, 13 Aug 2008 16:39:17 PDT

Teaching Pedagogy 101

Ronald W. Welch — Wed, 13 Aug 2008 16:39:01 PDT

What are the basics to consider in becoming an effective teacher? So you are a new faculty member just assigned a course and a textbook. Your only teaching experience is as a TA filling in for your traveling professor while teaching directly from your personal course notes taken when you took the course. Sound familiar? Where do you go? Who do you call? How do you quickly prepare yourself to be an effective teacher? Or maybe you have a few years of teaching experience and want to improve your performance as a teacher. Where do you start in preparing the course and the individual lessons such that the students are engaged in learning, and maybe entertained as well?This paper will try to answer these questions by offering helpful hints from a team of participants who recently completed the ExCEEd Teaching workshop and applied its lessons at their home institutions. The ExcEEd (Excellence in Engineering Education) Teaching Workshop sponsored by the American Society of Civil Engineers (ASCE) provides the content and structure for presenting the pedagogical basics that every teacher should know. The workshop consists of 12 seminars covering how people learn, what constitutes good teaching, and how to prepare a good class. We will focus on the key points necessary to kick-start a teaching career or to begin to immediately improve a career. Over 300 workshop participants from over 170 CE programs have been touched by the ExCEEd (Excellence in Civil Engineering Education) Teaching Workshops 1999-2003, the ExcEEd 2004 (Excellence in Engineering Education) Teaching Workshop, and the NSF funded predecessor "Teaching Teachers To Teach Engineering" (T⁴E) Teaching Workshops 1996-1998. This does not include the Mechanical, Electrical, and Chemical faculty members who have participated in T⁴E and ExcEEd. Five years of long term assessment data will be summarized to demonstrate the effectiveness and benefit of these pedagogical basics to the participants.