Twice a year I write a column about the semester’s Senior Design Project program at Pitt’s Civil and Environmental Engineering Department, culminating it with a statement to the effect that “if these students are typical of the young people graduating from college this year, our future is in good hands”. I am pleased to report that the Fall 2022 class is perpetuating that statement.
This year we had thirty-two students divided into eight four-person teams implementing a wide variety of projects, six in the Civil Engineering area and two in Environmental Engineering. In every case the students showcased their technical proficiency, their ability to work synergistically in a team environment, and their commitment to service to society.
I had the privilege of serving as a mentor for two teams. For the fourth consecutive term we were asked by a civic organization in Brownsville, the Perennial Project, to perform a preliminary design associated with the renovation of that community’s business district. This semester it was the replacement of three vacant business buildings with a modern municipal building housing fire, police, judicial, and borough facilities. The finished product is the design of a handsome three-story hybrid steel frame/precast concrete structure, sufficiently detailed to provide a basis for seeking funding.
The other team I mentored tackled a particularly relevant problem – temporary housing for the homeless community in Pittsburgh. Pittsburgh Councilwoman Deborah Gross has been spearheading this effort. After extensive study of the problem our students recommended the construction of twelve “tiny houses” and a modest community center on a vacant property in Homewood. Their efforts included a comprehensive study of transportation alternatives for disadvantaged persons, a detailed design of the wood frame houses, a site plan, and an estimate of the total cost.
“American Rivers” is a powerful non-profit organization dedicated to bringing “rivers back to life by removing dams, replacing culverts, and restoring floodplains.” Five years ago one of our teams worked with them on the elimination of an obsolete dam on Neshannock Creek at Volant. This term it was a small dam on Shafer Run, in the Laurel Highlands, originally built to divert water to a recently discontinued fish hatchery. Its removal will eliminate an environmental barrier and ensure biological diversity to a pristine community of native brook trout.
In contrast with these “real-world” projects, this semester we had two bridge design projects that were theoretical, but possessed “real-world” characteristics. When the Fern Hollow bridge was being replaced on an accelerated schedule, the decision was made to construct it of pre-stressed precast concrete girders, primarily because of supply chain problems with fabricated steel. One of our teams elected to produce an alternative design, using steel plate girders connected continuously in three spans supported by two piers. The finished design, estimated to cost thirty-four million dollars, is an excellent confirmation of the continued applicability of fabricated steel for major bridges.
Replacement of major bridges always is accompanied by massive disruptions to traffic. One approach to mitigate this is to replace the existing bridge in lateral stages, maintaining alternating one-way traffic in half the bridge while the other half is replaced. This was recently done in Monroeville for the bridge carrying Center Road over the Pennsylvania Turnpike. One of our teams studied an alternative design, a new bridge located alongside the existing one with an adjusted roadway to accommodate it. The result was another steel plate girder bridge, this one with horizontally curved girders. Construction of the bridge without disrupting traffic on the Turnpike was a major challenge.
“Riverlife” is a significant nonprofit organization dedicated to revitalizing the banks of Pittsburgh’s three rivers and making them accessible to the general public. The final Civil Engineering project, executed in conjunction with them, was the design of the portion of the Three Rivers Heritage Trail between 27th Street and the 31st Street Bridge in Lawrenceville. This portion is multi-purpose, with a focus on access from rivercraft as well as for hikers and cyclists. Connection with the 31st Bridge providing access to the Trail on the North Shore was a major challenge for this team.
One of the Environmental Engineering teams chose to study a major problem for the Pittsburgh Water and Sanitary Authority (PWSA) – response to episodic pollution events in the Allegheny River, source of fresh water for their Aspinwall water treatment facility. The team’s solution was a combination of three components – the installation of “early warning” monitoring stations in four upriver locations, the automation of the existing facility using a Supervisory Control and Data Acquisition (SCADA) system, and the addition of an activated carbon treatment system to handle such events.
The other team studied the remediation of a (former blast furnace) brownfield site in Duquesne. Based on soil sampling they determined that the soil on the site contained dangerous levels of four toxic metals – lead, vanadium, thallium, and iron. Their final design included three drastically different remediation technologies, each appropriate for a portion of the site – phytoremediation (use of appropriate vegetation), capping with a non-permeable membrane, and soil washing. The net result would be a site available for commercial development in a minimum time and at a minimum cost.
Each of the teams presented its project in a forty-five minutes long video for review by client, faculty, and industry specialists. They then participated in a thirty minutes Question and Answer session with these reviewers. The quality of the presentations and the extemporaneous response of these students to questions and comments from the reviewers were outstanding.
Kudos to program coordinator John Sebastian for another outstanding semester. We were impressed with the client representatives, the faculty and industry mentors, and the industry reviewers (which included numerous Department alumni). Most of all we were impressed with these thirty-two students, who once again renewed our optimism in the future. The torch has been passed to Generation Z!