Brief Design/Build/Remove Assignments For Structures Courses

Two types of brief student assignments to design and build rudimentary structures that are big enough to stand under have enhanced understanding of a variety of structural planning, design, and construction issues. Problem statements, grading criteria, and examples of completed projects illustrate the use of this vehicle to augment the study of building stability and behavior of non-horizontal roof structures. Among the benefits discussed are the opportunity to see three-dimensional deformation, develop a feel for forces in materials, and experience some of the ways that the building process influences planning and design decision-making. It is believed that these projects are adaptable to a range of architectural engineering courses and topics. Introduction Engineering and architecture faculty employ a wide variety of assignments to simulate the experience of designing and constructing buildings. Most often these are small models or segments of the process, but some attempt the construction of entire structures. The central 1 objectives of these projects are (1) To help students synthesize and attach physical meaning to the qualitative and quantitative elements of their academic coursework and (2) To foster heightened intellectual and emotional commitment to their studies. However, it can be very difficult to devise a project that does not require inordinate amounts of faculty and student time when the goal is to illustrate the entire design, build, remove process with structures that are large enough to provide a real sense of building forces. Observations of the beneficial results of two assignments that require relatively little contact time and (if carefully monitored) reasonable expectations for students are offered as examples that may be adapted to illustrate many issues at various levels of architectural engineering education. There seem to be at least three characteristics of these projects that must be addressed at the outset. First, the size of the constructed object must be appropriate. Structures that have been big enough for adults to stand under with arms outstretched in every direction have proven far more successful than the alternatives. Second, since few students have experienced the entire process of designing and building an object larger than themselves, with others, as a course assignment, the uniqueness of such a task must be balanced by a limited scope of stated requirements. These are the types of projects wherein integrated experience is the greatest reward for the students and positive accounts from “veterans” of earlier years are the most convincing evaluations for the instructor. Third, the assignment is, in itself, a design task for the instructor that requires thoughtful consideration of the “clients”, “site”, and resources. Consequently, the following account of two projects describes the specific context in which they are assigned, provides problem statements of requirements and evaluation criteria, reports some examples of both technical and general learning that may be observed, and offers some concluding remarks. P ge 291.1 Context Students enrolled in a twoor three-year curriculum leading to the Master of Architecture degree are required to take a one-semester, 1 unit (4 credit hours) course titled Structural Planning. The course is intended to help students achieve sufficient understanding that they may participate knowledgeably in the selection of appropriate load-carrying systems for buildings. Since they must have the equivalent of a pre-professional baccalaureate degree in architecture, they are assumed to have had a background in statics, strength of materials, and elementary design of steel, reinforced concrete, and timber structures. However, the extent of their knowledge and confidence in it is ordinarily represented by an extreme range between students in each class. Also, the course serves those students not specializing in architectural structures; consequently, the topic must be presented in a way that appears to be relevant to other, higher priorities. However, they are able to learn computational procedures at a level of complexity represented by the provisions of ASCE 7 (e.g.; gravity, wind, and seismic forces applied to a simplified 5-story 2 reinforced concrete structure) and do have substantial backgrounds in architectural design, technology, and history. Perhaps most importantly, they are usually mature and motivated to succeed in their intended profession. Enrollments vary from 25-43 per semester. The following course outline indicates the topic for each meeting but omits the information that each session consists of two 50-minute periods. The assignments to design/build/remove structures may be identified as “P5: Stability Systems” and “SP ”, respectively. Each of the 2 projects requires one period for introduction and the equivalent of one-half to one period, spread over several sessions, to do the planning and design. The Stability Project requires two periods (one session) for presentation and the Structural Planning Project (SP ) requires four to six 2 periods (two or three sessions). These projects are built and demonstrated outside. Presentations are postponed only in the event of lightning, severe weather warnings, or temperatures below 0 (F. Initial instructor’s comments about the projects encourage students to anticipate the weather as they consider the advantages of various designs and details that facilitate construction. The Stability Project The notion of this project stemmed from an attempt to help students understand lectures on the concepts of stability and the behavior of stabilizing systems. The characteristics of buckling, overturning, and sliding can be illustrated by smaller scale models. Also, with a bit more effort, representations of diaphragms and various types of bracing systems can be effective at smaller scales. But, to illustrate the three-dimensional transfer of forces in unsymmetric joints that are influenced by torsion, to see the warping effects of unsymmetric bracing systems, or to experience the sight, sound, and feel of a failed fastener, connector, or member, it is necessary to build at a larger scale. Students are encouraged to use inexpensive materials and element sizes that will illustrate deformation. For example, cardboard connectors serve well to illustrate bearing, shear, and buckling in gusset plates. Polyethylene sheeting stapled to a frame displays the direction of primary forces and shear flow at the fasteners. Elastic cord, springs, or rubber sheeting at Xbrace intersections display alternating tension and compression.