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As an environmentally friendly technology, microbially induced calcite precipitation (MICP) is widely used to improve the engineering properties of soil. The goal of this study was to investigate the effect of rainfall-induced erosion on the stability of sandy slopes which were treated by MICP technology. The observation of the erosion pattern of low concentration (0.25 M Ca) and high concentration (0.5 M Ca) of MICP-treated slopes, the mechanical behaviors of MICP-treated and cement-treated samples, and the effects of rainfall-induced erosion on the roughness of 0.5 M Ca MICP-treated and 10% cement-treated slope were studied through visual observation, unconfined compressive tests, and roughness tests. For the 0.25 M Ca MICP-treated sample, surface erosion was found to occur soon after the start of the rainfall erosion test, while for the 0.5 M Ca MICP-treated sample, the slope surface remained intact after exposing to the rainfall for 24 hours. Through unconfined compressive tests, it can be concluded that the 0.5 M Ca MICP treatment achieved a high strength, which was similar to 10% cement-treated sand. The roughness test results showed that the surface of 0.5 M Ca MICP-treated slope looked smoother than the uneroded surface after 24-h rainfall-induced erosion. On the contrary, the surface of the 10% cement-treated slope became rougher after 24-h rainfall-induced erosion. These results indicated that the MICP-treated sandy slope had lower resistance against rainfall-induced erosion compared to the cement-treated sandy slope. 

This Innovative Practice Full Paper presents findings from the implementation of a virtual reality-based learning module. In the Fall of 2020, a prototype for a novel intervention namely, Virtual/Augmented-Reality-Based Discipline Exploration Rotations (VADERs), was offered as part of the first-year Introduction to Architectural Engineering (AE) classes at two universities. VADERs will ultimately be a collection of modules that are designed to improve student engagement and diversity-awareness by providing interactive virtual explorations of an engineering discipline and its sub-disciplines. VADERs utilize an open source, device-agnostic, and browser-based three-dimensional Virtual Reality (VR) platform, creating unique accessibility, synchronous social affordances, and media asset flexibility. The conjecture explored in this paper is: Having first-year engineering students experience Architectural Engineering and its sub-disciplines through an interactive VADER module, will improve their self-efficacy in regards to their commitment to studying the discipline. A total of 89 students participated in the VADER pilot in Fall 2020. Complete data was collected from 67 of these participants in the form of pre- and post- surveys, and final project deliverables. Results tied to the hypothesis and recommendations for future related work are discussed.