PYRRHOTITE IN CONCRETE: TRINITY COLLEGE UNDERGRADUATE STUDENT RESEARCH

A major component of the pyrrhotite testing program at Trinity College’s Environmental Science program (ENVS) is undergraduate student research. As undergraduate educators we find that students are eager to engage in projects that have societal relevance. The crumbling basement issue certainly fits this description and we’ve attracted many students to work on the problem. In 2018 the ENVS program at Trinity started its testing program and involved students from day one. Students have contributed to the development of ENVS’s testing procedure using a combination of two independent tests: a physical magnetic susceptibility loss analysis and a chemical total sulfur analysis. These analyses are used to accurately quantify pyrrhotite in concrete samples where it exists and have successfully tested over 400 private homes in both Connecticut and Massachusetts. In addition, several students have engaged in a multitude of side projects that have helped advance our understanding of various pyrrhotite phases, the rocks in which pyrrhotite is locally found and the reaction of pyrrhotite to secondary minerals. These projects include: 1) XRD analyses in an attempt to fingerprint rocks originating from pyrrhotite rich source rock 2) statistical analyses of our growing data set to assess risk, 3) visual assessments of foundation deterioration through photographs and homeowner questionnaires, and 4) controlled lab experiments that examine the interaction of water and air in the pyrrhotite reaction. This poster highlights some of this on-going work and some preliminary findings.