Mr. Ed Dalrymple (center of photo in green hat) explains the making of aggregate to students. "We are grateful for his generous involvement, " said Burak Tanyu, assistant professor in civil engineering. "Without his support, this field trip never would have happened."
When college students say they had a blast, they typically don't mean watching 20,000 lbs. of explosive power blast 40,000 tons of rock, but that's how senior civil engineering student Rachael Wright described her field trip to Cedar Mountain Quarry.
Wright was one of 40 students from associate professor Burak Tanyu's geotechnical engineering class who donned bright orange hard hats on a crisp fall morning and toured the 1,500-acre quarry just south of Culpeper in the Shenandoah Mountain foothills.
"It was thrilling to see the explosion," said Wright. "I had seen a quarry explosion on video before, so I wasn't expecting it to be so exciting. But seeing a video is nothing like being there, watching rocks fly forward, seeing dust billow out from the rubble, and feeling the force of the explosion through the air before hearing it. It was surreal."
Tanyu designed the field trip to teach students about geological formations and what it takes to make the rock aggregate that forms the basis of many Virginia roads. His class combines two fields of study, geotechnical engineering and geology, that are often separate. Geotechnical engineering focuses on soil and geology focuses on rock.
"The class gives prospective geotechnical and civil engineers a background and understanding of the earth's history and processes so they can understand the implications of how these relate to engineering problems such as earthquakes and landslides as well as making educated assessments for suitable ground conditions and selecting appropriate soils and rocks for construction."
Tanyu quotes the famous saying in geo-engineering field. ‘Virtually every structure is supported by soil or rock unless they fly, float, or fall over.' He emphasizes that accurate characterizations of surface and subsurface conditions are key to building any structure designed by civil engineers.
"Rather than merely memorizing the most common rocks we might see in our work," said Wright, "we are learning how they get there, how to describe them, and what it means when we see certain formations. In short, this class isn't just teaching us about geology, it's teaching us what we don't know about geology. We're learning when it's important to learn more and seek advice from an expert."
The students saw the rock before the blast in its natural formation and after the blast as small pieces of rock that could be used in construction. It changed hundred-ton rocks that aren't useful for construction to sizes that can be used for the aggregate in highways and roads. The blast is an essential because it minimizes the time and cost of changing large rock formations into smaller pieces that can be further handled to create engineered products.
"We could recognize the texture of the quarry walls and minerals we had covered in class in the rocks on the site," said Wright. "We saw things in the field we had talked about in class. It was interesting to watch them place explosives, learn the reasoning for what they wanted to happen, then watch massive rock formations explode into small pieces."
Tanyu could arrange this field trip because the owner of Cedar Mountain quarry, Ed Dalyrmple, asked him for an on-site meeting to discuss the details of a research project that focuses on developing sustainable solutions to expand roadway designs in Virginia.
"The people at Cedar Mountain Quarry told me they had never hosted such a visit because most researchers do not bring their students to these meetings," said Tanyu. "I saw the opportunity to kill two birds with one stone and I know the students benefitted."
