2026 ASEE Annual Conference & Exposition

Students entering a mechanics of materials course often have difficulty visualizing how a structure or assembly can fail in different ways due to normal and shear stresses. In particular, they can struggle to identify relevant combinations of load and area necessary to calculate potential critical stresses at different locations in a system.

To address this issue, an activity was designed to help students think through different ways simple assemblies can fail and identify the correct combinations of load and area needed to calculate the stress associated with each potential failure. This activity incorporates low-cost, easy-to-manufacture physical manipulatives along with questions designed to scaffold exploration of the topic. It can be completed by small groups of students in one 50-minute class period. In developing the activity, the hypothesis was that the active-learning, inquiry-based approach would improve student ability to calculate stresses associated with potential failure modes.

A pre- and post-test related to normal and shear failure was used to evaluate the effectiveness of the activity in promoting student learning. In addition, a survey was used to interrogate students’ impressions of the activity and how they perceived it helped them learn. The activity was piloted in Fall 2025 in a mechanics of materials class with 30 students, who all provided pre/post testing and survey data. Examination of the pre/post test data reveals that the majority of students did improve their performance when analyzing a scenario involving shear and normal stress after the activity. Examination of the survey data indicates that students enjoyed the activity and that they felt it helped them better understand normal and shear stress failure. Students particularly praised the physical manipulatives and group discussion.