ASEE Prism Magazine - Oct 2001

 

 

Teaching TOolbox

On Campus - New Solutions for Old Bridges

- By Barbara Mathias-Riegel

Jai Kim and his students at Bucknell discuss the plan to add reinforcing cables to a bridge they are helping to save.It's a good thing the civil engineering lab at Bucknell University is a substantial size, because in it sit two 36-foot round logs cut from 60-foot used telephone poles, complete with a small dose of creosote. It's a timber bridge designed and built by two civil engineering students, Megan Strand and Linda Steele. Commissioned by the Borough of Lewisburg, Pa., the bridge will cross over a small stream in the township.

The job is done, but the logs remain until the abutment of the existing bridge is removed. Jai B. Kim, chairman and professor of Bucknell's department of civil and environmental engineering, doesn't seem to mind the delay. He likes looking at them every day. “They are very romantic,” he says.

“Romantic” may seem a funny word, but Kim is passionate about bridges and especially about the preservation of historic bridges. It all began nearly forty years ago when he was an undergraduate at Oregon State and designed a logging bridge for a lumber company. From there he went to Bucknell where he taught and developed the Bucknell System, a method of strengthening metal-truss bridges by building new arches that help carry the stress load on the pin connections. Now a consultant on metal-truss bridges, Kim brings his passion into the classroom where his students routinely watch videos on historic bridges.

“Think about the Romans,” Kim tells his students. “They have 2,000-year-old-structures; we don't even have 100-year-old bridges. When I read about dynamiting the bridges, I get sick.”

He also gets busy. To date, Kim has supervised nine bridge projects with his students. His most recent is the 132-year-old Henszey's Wrought-Iron Arch Bridge that spans Ontelaunee Creek, situated on rich farmland near Harrisburg, Pa., about 90 minutes from the Bucknell campus. Ninety-two feet long and 18 feet wide, Henszey's bridge is a handsome sight, with its wooden floor and bow-like arches. In 1985 it was deemed unsafe and shut down with cement barricades at both ends.

“It sat on the site and was just rusting out until the president of Central Pennsylvania College, a 600-student proprietary institution near Harrisburg, called the Pennsylvania Department of Transportation and asked if they had any old spans,” says Kim. “He thought that connecting the campus to the new academic building with a bridge would bring good and new visibility, sort of, the old for the future.”

Milano bid a whopping $22 on Henszey's and won. Next he called Kim and asked if Bucknell's engineering department would figure out if the bridge could be saved and how much it would cost. Of course Kim agreed, but with some major considerations.

“The liability issue gets to be very complicated,” explains Kim. “Five years from now when something happens to somebody on the bridge, who is going to be responsible?” He adds that there is also accidental risk when the bridge is transported to its new site. The solution was a signed agreement with Central Penn that neither Bucknell, the students, nor Kim can guarantee the bridge report, and that it is for information purposes only.

At the beginning of their senior year, four engineering students were selected to produce a feasibility study and a design. Under Kim's supervision, they made numerous trips to the bridge where they measured every rod and arch and calculated their findings into their structural-analysis software. Back at the studio, they designed a way to reinforce the chords through a series of loops and new pieces. Finally, they estimated that the moving and rehabilitation would cost about $260,000.

Their study is being reviewed and certified by a consulting engineering company in Albany, New York and a contractor has been assigned to carry out the work. And when will that be? “It will happen soon, probably this summer,” says Kim. His pride in the part his students played in saving the Henszey is clear. “I don't know anybody who doesn't love a bridge.”

Barbara Mathias-Riegel is a freelance writer based in Washington, D.C.

 

On Campus - early to Engineering

- By Barbara Mathias-Riegel

It's one thing to recognize the need for a pre-engineering curriculum at the high school level, but who is going to teach such courses without special training? And how will schools keep up with the latest developments in engineering technology, which can be costly and complex to learn?

Richard Blais has the answers. Through the generosity of the Charitable Venture Foundation of Albany, N.Y., Blais and an exemplary group of educators have designed a pre-engineering curriculum for public schools that is affordable and highly professional. They call it Project Lead the Way (PLTW), and it's like no other plan around.

“We have basic quality standards that we insist upon,” says Blais, who is the executive director of PLTW and has been working on this since 1985.

According to Blais, when a school signs a contract with PLTW there is no exchange of money. Instead, the school agrees that their teachers will be trained and PLTW is obliged to provide that training, as well as a curriculum. PLTW also provides a computer software leasing program and ongoing, on-site training with visiting trainers and interactive CDs.

Most important, the school agrees to form a partnership team, drawn from members of local industries and colleges, who will actively assist teachers with instruction in specialized areas and mentor the students.

“The content of the courses is advancing with events in modern technology,” says Guy Johnson, the director of the PLTW's National Training Center at Rochester Institute of Technology (RIT). “We have a group of master teachers and professors who do revisions constantly.”

That curriculum is a four-year, five-course set for high schools and a one-year introductory course at the middle school level; students interested in engineering can take design, digital electronics, principles of engineering, and computer integrated manufacturing.

“There's a strong commitment within the organization to make the curriculum documents be living documents,” says Ken McDermith, a technology teacher at Mohonasen High School in Schnectedy, NY, where the hands-on, team-oriented PLTW courses have been enthusiastically received by the students for the past three years.

After taking the PLTW training, McDermith used it in his classroom for one year, qualifying him to be a “master teacher,” meaning he now teaches at RIT's training center along with a college professor. The summer training is a 75-hour, two-week session for each course. “There is so much talent at (RIT) in the summer time. It's amazing,” says McDermith. “Everybody has a niche, and you learn so much from them.”

According to Johnson, “These courses are more than just content. Thirty to 50 percent is on methods and that's where the master teachers are crucial. They know what it is like to teach at the high school level.”

Before registration, teachers must take a pre-assessment test available on the Internet. Once on board, the teachers pay nothing. Their training, lodging, transportation, and stipend is covered by their state and/or school.

In 1998, 79 teachers trained at RIT; two years later, there were 249 teachers. Currently, more than 300 schools in 26 states offer PLTW courses taught by trained teachers. Due to this rapid growth, several training centers are now affiliated with RIT: The New Hampshire Institute of Technology, Ferris State in Michigan, the University of Houston, the Rocky Mountain Regional PLTW training center in Denver, and soon, Purdue University.

“Purdue has agreed to be an affiliate in cooperation with the State of Indiana Department of Public Instruction. We have only a few administrative details to work out,” says Don K. Gentry, Dean of Purdue University's School of Technology. “We are major supporters of the ideals of PLTW.”

Jerry Foster, a professor of electrical engineering at Purdue, notes how often he has met high school teachers who were excited about the idea of teaching pre-engineering but then felt restrained for lack of support and guidance. No more excuses with PLTW around, says Foster. “When the schools buy into it, they buy into training and equipment.” For more information, go to http://www.pltw.org.

Barbara Mathias-Riegel is a freelance writer based in Washington, DC


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