IT-based interactive learning tools

The DAT tunnel construction simulation tool takes geologic and construction uncertainties as input and computes cost v. time, time v. distance, and time v. resource distributions, which are then used for risk analysis. Having been extended in several Ph.D. theses since 1973, the current DAT software is applicable for any simulation of linear or networked infrastructure and geothermal well drilling. As a learning tool, DAT is commonly used in term projects in 1.383 Underground Construction as well as M. Eng. theses.

Engineering geology classes at MIT are limited for field trips to a few geologic domains in the Boston area, e.g., glacial and coastal terrains. To fill that gap, the Physical Geology Tutor (PGT) was developed; the PGT includes an online illustrated textbook, a quiz module, and, most importantly, a “workbook” module that simulates field trips, in which students see and identify geologic features on screen. Originally developed in the 1980s, the PGT remains unique to date as a computer-based learning tool in engineering geology.

Simsection allows students to design tunnel cross-sections, which they will use with DAT to simulate tunnel construction. Novice learners, who do not have enough experience to specify dimensions and materials of tunnel supports, can choose from typical tunnel geometries in Simsection and then specify different types of tunnel supports. The learning module in Simsection does not prescribe supports, but alerts users if selected dimensions are too small or too large to be practical; thus students learn interactively through trial and error.

The NOMAD computer-based learning tool enabled users to create three-dimensional geologic profiles from surface and borehole information. Automatic adjustment of intersecting layer boundaries was a major innovation for its time; up to that point profiles had to be connected by hand between 2-D cross sections. In addition to such algorithms for drawing judgement-based non-planar surfaces, the program had innovative features for spatial rotation and solid state modeling. After several updates, development of NOMAD was discontinued when commercial software providing similar functionalities became available.

Based on NOMAD, the Extended Geologic Profile Visualization module included additional capabilities to represent uncertainties and draw kriged profiles.

The Mechanics Module is an interactive module for learning fundamental concepts of mechanics, such as equilibrium and internal stresses. Students learn the concepts interactively by solving increasingly complex problems. For example, students can place, size, and toggle force vectors to create an equilibrium, both analytically and graphically. The Mechanics Module also presents real world examples of the concepts.

In engineering geology and rock mechanics one often has to solve three-dimensional (3-D) problems: e.g., rock bodies bounded by discontinuities can move. If this is done by transforming the 3-D geometry and 3-D force action into two dimensions (2-D), two major difficulties are understanding the 3-D problem and transferring from 3-D to 2-D. The Stereonet Module learning tool enables students to describe planes and to define, rotate, and translate rock bodies bounded by them in 3-D space. The tool can be used in a simplified mode, where students input the geometry and see a solution to the mechanical problem; students can also solve increasingly complex problems on their own. While the modeling capabilities of the Stereonet Module are similar to that of commercial software, the pedagogical components of this learning tool are unique.

The Tunnelliner learning tool uses a closed form analytical solution, developed by the research group, for designing a tunnel liner. The original research results included instructions for programmable calculators and diagrams that can be used to do the analysis. Based on that template, the interactive Tunnelliner program was implemented in Matlab, and includes a graphical user interface for defining geometry and material properties as input and obtaining graphs of stresses and displacements as output.