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Teaching Development Fund 1999/2000 Case Study Concrete Laboratory Teaching Video Project Leaders: Peter Walker and Tim Ibell Department of Architecture and Civil Engineering emails: firstname.lastname@example.org and email@example.com Context An essential element of any Civil Engineering degree is for students to see how concrete structures actually behave through to failure. This provides students with a ‘feel’ for concrete structures and equips them for advanced engineering design beyond the constraints of Codes-of-Practice. This element of a Civil Engineering degree is normally taught in a laboratory and typically consists of loading (to destruction) concrete structures of various form. The Department of Architecture and Civil Engineering has a main Structures Laboratory, where all research and taught testing is undertaken at present. This laboratory is of insufficient size to allow any sizeable teaching experiments to be conducted regularly. Therefore, up until this project, all teaching experiments on concrete structures have been carried out on very small specimens (concrete cubes of one litre volume and mini-beams of 500mm length). While important for general concrete understanding, these experiments are in themselves insufficient to demonstrate the full range of concrete behaviour to undergraduate students. Initial Aims It was felt imperative that our students watch the failure of reinforced concrete beams (each failing in different manners) and concrete columns in their second year of study, followed by prestressed concrete beams and concrete slabs (failing in different manners) in their fourth year of study. Given the space constraints in the main Structures Laboratory, it was felt that this would be best done by filming professionally these tests being carried out during Summer 2000 and then showing videos of these tests to future students in their second and fourth years. As part of a structured tutorial, we would require the students to predict failure modes and capacities prior to watching the videoed experiments, followed by submission of a laboratory report. During the laboratory write-up, students would be able to access the webpage for these experiments, which would contain video stills, tutorial sheets and all experimental data necessary to complete the laboratory report. This webpage would additionally serve as a repeatably-accessible resource for our students, of tremendous educational benefit. In this way, the laboratory constraints would be overcome, while simultaneously providing excellence in concrete teaching. To our knowledge, this approach was novel and a cost-effective compromise in order to educate our students properly. We also felt this teaching method would help keep focus on the experiments, due to the edited length of the video, rather than allow students’ attention to drift in a real laboratory. As evidence as to its viability, at the time of applying for this project funding, we learned that the British Cement Association was currently considering producing such a video, presumably for purchase by Higher-Education Institutions in the future. We felt we required this video rather more urgently than this, and one that was tailored to those facets of concrete engineering which we believe to be crucial. Project Implementation During the design of the experiments to be conducted and filmed, we decided to extend the scope from 3 reinforced concrete beams, 1 column, 1 prestressed concrete beam and 2 slabs to 4 reinforced concrete beams, 2 columns, 2 prestressed concrete beams and 2 slabs. This was done to include another three distinct failure modes in the virtual laboratory and also to show the behaviour of fibre-reinforced-plastic as reinforcing material for concrete structures of the future. The formwork for all specimens was constructed during July 2000 and casting of the specimens began on 4 August 2000 and lasted a fortnight. Testing and filming of the tests started on 6 September 2000 and lasted 3 days in total. One of the tests did not fail in the manner in which we had hoped and this specimen was recast, tested and filmed two weeks later. Apart from this particular specimen, all other aspects of the laboratory work went according to plan. A script for the video was written by the Investigators. Together with Mark Price of Audio Visual Aids, University of Bath, who had filmed all the tests, editing of the final video was carried out during the second week of February 2001, in time for 2 nd and 4th year students on their respective concrete design courses to witness and comment on the virtual laboratory system. Also during February 2001, all data from the tests was converted to graphical output and individual tutorial sheets (laboratory reports) for each test conducted were created. The webpage for the virtual laboratory was written and mounted at www.bath.ac.uk/~abstji/concrete_video/virtual_lab.htm. Versions of the tutorial sheets in .pdf format were added to the site, as were video stills at various load increments for each test. Feedback At this stage in February 2001, the final 22-minute video, accompanying webpage and tutorial sheets were ready for evaluation by 2 nd and 4th year students, as well as outside bodies. In particular, we approached The Concrete Society, a highly-respected learned society in the U.K. for their comments on the virtual laboratory package. They sent back very positive comments and they published an article in their 'Concrete' Journal about Bath University's initiative. This attracted a response from the South African Concrete Society, to whom we also sent the full package for comments. They too were very supportive of the concept and now plan to carry out a similar project themselves. In terms of detailed feedback from our own students at Bath, the following summarises the 'scores' out of 5 which were allocated in the most important three categories from a total of 61 returns: Importance of the video as a teaching resource 4.0 Quality of the tutorial sheets and webpage 4.2 The concept of a video as a substitute for real testing 3.8 We feel that these average scores reinforce the success of the project. However, it must be conceded that students obviously felt slightly ill-at-ease with the video becoming a pure substitute for physical testing, judging by the marginally-lower score in this category and by some comments received. The intention of the virtual laboratory was never to entirely replace all physical testing on concrete structures, but rather to expand the number and range of tests offered to students. This point will be made clear to students this coming academic year. It has not been felt necessary to alter anything about the overall package based on all feedback received. Key Advice We found that the help of an experienced cameraman and editor was vital to the successful creation of a professional video. Without such help, the quality of the video would have suffered. When we initially introduced the virtual package to our students, we did not fully explain the background and circumstances surrounding the idea of using such a system as a backup, not a substitute, for physical laboratory testing. This will be rectified in future. Our advice would be to explain clearly to students the advantages of any innovative teaching aid before thrusting it upon them.
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