Introductory steel design courses focus on the analysis and design of primary members, which typically include tension members and connections, compression members, flexural members, and beam-columns. Introducing structural steel design concepts to students presents its fair share of challenges. First, it is difficult for students to visualize and accurately predict the potential failure modes of a tension member: yielding of the gross section, rupture of the net section, and block shear. Second, it is also difficult for students to visualize the buckling modes of steel columns, which vary with shape and type of bracing. Students particularly struggle with the determination of buckling modes between strong and weak axes based on effective lengths. Third, flexural failure modes of steel beams are very difficult for students to visualize and understand when each mode controls. The failure modes are complex and fall into three categories for compact shapes: yielding of the cross section, inelastic lateral torsional buckling, and elastic lateral torsional buckling, which is dependent on the unbraced length of the compression flange. Non-compact sections also include local buckling of the flange or web, but identifying the relationship between the unbraced length and beam span and how the unbraced length affects the flexural capacity tends to be the most difficult concept for students to grasp.
This paper provides a detailed overview of the design, fabrication, and implementation of three large-scale experiential learning modules for an undergraduate steel design course. The first module focuses on the tension connections by providing physical models of various failure types including yielding of the gross section, rupture of the net section, and block shear; the second module focuses on the capacity of columns with different amounts of lateral bracing about the weak axis; and the third module focuses on the flexural strength of a beam with different unbraced lengths to illustrate the difference between lateral torsional buckling and flange local buckling/yielding of the gross section. The three modules were used throughout the steel design course at Saint Louis University and Rose-Hulman Institute of Technology to illustrate the failure mechanisms associated with the design of steel structures.
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Design and Implementation of Experiential Learning Modules for Reinforced Concrete
Most undergraduate civil engineering programs include an introductory course in reinforced concrete design. The course generally includes an introduction to the fundamentals of reinforced concrete behavior, the design of simple beams and one-way slabs to resist shear and flexure, and the design of short columns. Because of the scale of typical civil engineering structures, students commonly do not get to experience large or full-scale structural behavior as a part of an undergraduate reinforced concrete course. Rather, students typically learn fundamental concepts through theoretical discussions, small demonstrations, or pictures and images. Without the interaction with full-scale structural members, students can struggle to develop a clear understanding of the fundamental behavior of these systems such as the differences in behavior of an over or under-reinforced beam. Additionally, students do not build an appreciation for the variations between as-built versus theoretical designs. Large-scale models can illustrate such behavior and enhance student understanding, but most civil engineering programs lack the physical equipment to perform testing at this scale. The authors from St. Louis University (SLU) and Rose-Hulman Institute of Technology (RHIT) have designed and implemented large-scale tests for in-class use that allow students to experience fundamental reinforced concrete behavior. Students design and test several reinforced concrete members using a modular strong-block testing system.
This paper provides a detailed overview of the design, fabrication, and implementation of three large-scale experiential learning modules for an undergraduate reinforced concrete design course. The first module focuses on service load and deflections of a reinforced concrete beam. The first and second modules also focus on flexural failure modes and ductility. The third module focuses on shear design and failure modes. Each module uses a large scale reinforced concrete beam (Flexure specimens: 12 in. x 14 in. x 19 ft, Shear specimens: 12 in. x 14 in. x 10 ft.) that was tested on a modular strong-block testing system. The three modules were used throughout the reinforced concrete design course at SLU and RHIT to illustrate behavior concurrent to the presentation of various reinforced concrete design concepts.
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- Award ID(s):
- 1726621
- NSF-PAR ID:
- 10288932
- Date Published:
- Journal Name:
- ASEE annual conference exposition
- ISSN:
- 2153-5965
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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