A Visit to Italy with a Group of High School Students
When Ryan Decker traveled to Italy with a group of high school students this spring, he was surprised to see how little some construction techniques have changed over time. As students were absorbing the art and culture, Decker, Corporate Quality Assurance Manager for F.A. Wilhelm Construction, was looking at the ancient structures through the eyes of a builder.
Decker served as a chaperone on the trip with his wife Leslie, a North Central High School English teacher and 18 of her students. They visited the Pantheon, Saint Peter's Basilica, The Forum, as well as traveling to Naples and Florence where the saw the ruins of Pompeii and The Duomo.
Decker said the trip was like visiting "the mecca of original construction." "One of the things that really blew me away was the Colosseum," he said. "You're looking at a structure that was built 2,100 years ago using the same basic design we use to build coliseums today, and it's still standing."
Within the superstructure of the Colosseum, Decker could see clues about its construction - details that most people miss. While the tour guide spoke of history - ancient rulers and life during Caesar's reign - Decker was using his smartphone to learn more about how the Colosseum was constructed. He wanted to know what type of stone they used, the basics of Roman engineering, and the means and methods employed to build such a massive structure in ancient times.
The superstructure was built with travertine stone, a type of limestone building material still used in modern-day structures mainly as the most durable stone floor tile and a faÃ§ade of marble. As Decker learned more about Roman construction techniques, he was surprised to see how similar they were to those used today.
To lift the largest stones for the walls of the Colosseum, they used wooden derrick cranes equipped with pulleys, counter weights and what has been referred to as a "human hamster wheel" that created the power necessary to set the massive travertine stones within the Colosseum. These derrick cranes are similar in function to derrick cranes found on construction sites today. The Romans used slaves to do the heavy lifting. Slaves climbed into the wheel and walked. As they walked, the wheel would turn, lifting the massive stones attached to the ropes that moved over pulleys at the top of the crane.
"At some point," Decker said, "they realized they couldn't build the whole thing out of travertine limestone because it would have been too heavy to support its own weight." In order to reduce the weight bearing down on the limestone, they used the classic Roman arch to distribute these loads. Many of the arches where built using brick or Roman concrete - a mixture of volcanic ash, lime, water, pit sand, stone or rubble.
They also handset brick and then filled and covered the brick with concrete - an early version of cast-in-place concrete techniques commonly used in modern construction. "You can still see remnants of the boards used to form the concrete."
Inside the stadium, Decker said they used raker beams, angled notched beams structurally similar to those found in modern day arenas, to support the seats.
Decker noted that the concrete used in construction today may not appear to last as long as the concrete the ancient Romans used. He explained that while it is still manufactured out of the same basic materials, today's concrete hardens much more quickly than the mixture of volcanic ash, sand, stone, and water used to build the Colosseum and other structures. Decker said that given the lower temperatures of hydration, the concrete the Romans used could have taken as long as two years to fully hydrate and gain enough strength. He explained that a longer, slower hydration period would make the concrete more durable and stronger.
Decker's curiosity and enthusiasm about what he was seeing did not go unnoticed. "The kids knew I was in the construction industry and would follow me off to the side and ask me questions about what I was looking at." Recognizing his interest and expertise, the tour guide handed Decker the microphone and asked him to explain the construction techniques used to build the Colosseum.
"I'm not an educator or a teacher," Decker said. "I do something totally different than what these kids are exposed to every day at school." He was able to share his knowledge of today's construction methods and compare them to the ancient building methods and materials thus linking the past to the present. He also stressed the fact that these building were designed and constructed without the aid of computers, CAD and construction layout programs and were able to build something that was nearly perfect.
It's not surprising that Decker sees so many connections between construction design and techniques of the past to those used in the present. As a quality Assurance Manager, his job is to do the research and find answers - to learn how new materials or construction standards will impact Wilhelm's projects. His assistance helps Wilhelm continue to be a leader in the construction industry completing landmark projects that improve the lives of our community.
For Decker, this trip offered a rare opportunity to see the ancient foundations upon which modern construction was built and to share that with students he was with and others here at home.