Experiencing Failure - Recreating the Hyatt Regency Collapse to Teach Statics, Ethics, and Lifelong Learning

The Hyatt Regency Hotel disaster continues to be an important civil engineering ethics casestudy. In engineering statics, this disaster is used to teach students about lifelong learning, the importance of licensure and ethics in engineering design and build. The assignment has evolved over the years and now includes a demonstration, free-body diagram and statics analysis. The demonstration and statics analysis of the original design and as-built conditions are completed before the Hyatt Regency disaster is described. Students are initially provided with schematics of the original and as-built designs and tasked with drawing the free body diagrams, completing the statics analysis and explaining the difference in the two systems. During the following demonstration, students load weight on scale models of both the as-built and original design configurations of the suspended walkways of the Hyatt Regency Hotel. In both cases, the models are loaded to failure and the total weight added before failure is compared. After a short discussion, a video of the Hyatt Regency Hotel tragedy is shown. The in-class assignment is followed up with a reflection paper assignment. In a survey administered to students in the course during fall 2017, 89 percent of student respondents (n = 48) indicated the activity added to their understanding of the topic and indicated in descriptive questions that the activity was helpful and increased their interest in engineering. Introduction Due to the nature of civil and mechanical engineering projects, it is vital for practitioners to uphold ethical standards during the engineering design process. As educators, we have a responsibility to expose students to the importance of ethics and consciousness in their decision and design making process. The Accreditation Board for Engineering and Technology (ABET) reinforces the need for teaching ethics in engineering programs with the inclusion of learning outcomes that address ethics. The new ABET Outcome 4 requires students have “An ability to recognize ethical and professional responsibilities in engineering situations and make informed judgments, which must consider the impact of engineering solutions in global, economic, environmental, and societal contexts” [1]. One method of teaching about ethics in engineering is to use case-studies of engineering disasters where there was room for a different ethical decision to be made. This can be done either in an engineering ethics course or embedded throughout the curriculum. This paper discusses the use of the 1981 Hyatt Regency disaster to introduce engineering ethics in a lower division engineering course: engineering statics. Methods This lesson in engineering statics uses the Hyatt Regency failure to integrate ethical decision making into the course and to show students how a simple statics problem was the cause of the tragic event. In the first stage, students are presented with the worksheet shown in Figure 1 and asked to draw free body diagrams and use statics to determine the reaction forces in different components of the system. This is performed in small groups and after most groups have finished, the solutions are worked through collaboratively on the board. The configuration difference between the original and modified design results in a significant change to the internal forces in Nut/Washer B. This difference is highlighted on the board. During the problem solving, students are not given any further context as to why the change in the design was made or information about the Hyatt Regency disaster. In the second stage of the lesson, students conduct a hands-on demonstration that models their own calculations to destructive failure. A schematic of the demonstration is shown in Figure 2 with a picture of students loading the demonstration shown in Figure 3. In the demonstration, the skywalk cross-beams are modeled with Styrofoam and the skywalk decks are thin planks of wood that bear on the demonstration’s wood frame at the ends and on the Styrofoam crossbeams in the center. The demonstration has two interchangeable setups. In one setup, continuous threaded rods connect from the top of the demonstration’s wood frame through both Styrofoam cross-beams to model the original design. In the second setup, the rod is discontinuous at midspan and the washers and nuts to support the rods bear on the center Styrofoam cross-beam. The demonstration was based on a model shown in a YouTube video posted by Ben Unruh [2]. The demonstration is first conducted for the modified design with students loading weights on the skywalks until the threaded rod anchors pull through the Styrofoam. The total load at failure is noted. Once the system fails, the failed Styrofoam cross-beams (labeled B in the schematics), and the rods, bolts and washers are passed around for students to inspect. The demonstration is set up a second time with the original design – one single rod supporting the Styrofoam crossbeams. Again mass is added to the skywalk until failure occurs. Students are able to confirm their own calculations that found the original design requires a larger load for failure. The failed Styrofoam cross-beams, and the rods, bolts and washers and rods are shared with the students to inspect. In the third stage of the lesson, the video “Hyatt Regency Skywalk Collapse 30th AnniversaryKCTV News Special” is played in class [3]. The 13-minute news segment, available on YouTube, outlines the disaster and its impacts 30 years later. The video is very powerful, so time is reserved at the end of class for open discussion where students are able to voice their thoughts and a discussion around ethics and responsibility is encouraged. The fourth and final stage of the lesson is a homework assignment where students reflect on the disaster and what they learned. A snapshot of the assignment is presented in Figure 4. In particular, the assignment asks students to reflect on the ethical repercussions of the change in the design and how they can and will use ethics and compassion in their careers as engineers. The intentional order of the stages allows students to first focus on the statics with no knowledge of the skywalk failure. The following destructive testing on the two models is exciting for students and, importantly, gives them a visual confirmation of the validity of their own calculations. The energy and mood of the room dramatically changes when the serious and deadly repercussions of this seemingly simple design change is revealed in the video. The final requirement of a reflection assignment gives students the opportunity to sit with their thoughts and consider the implications of this disaster on their own future careers.