Hopkins students propose pedestrian bridge

In response to the growing number of pedestrian accidents in Charles Village, three seniors from the Department of Civil Engineering were inspired to write a proposal for the construction of a pedestrian bridge across Charles Street. The team includes Erin Kelly, Charlotte Healy and Alison Ignatowski, with project advisor Dr. Rachel Sangree, a lecturer in the Department of Civil Engineering.

"There is a major culture clash around the Hopkins camps between drivers and pedestrians — both feel entitled to the road, and neither follows the rules. The pedestrian bridge would eliminate this clash and provide the safest route for students on campus," Healy wrote in an e-mail to The News-Letter.

With its thousands of daily pedestrians, Charles Street has proven to be dangerous, even fatal, for students and local residents. Despite the steps that Hopkins and Baltimore City are taking to improve pedestrian safety by the Charles Street Reconstruction Project, the engineering team believes that the only way to truly solve the problem is to build a pedestrian bridge as a safe crossing method.

"Several other universities and high schools in the immediate area, including Loyola University, which is only a mile north of campus, have constructed pedestrian bridges to eliminate the dangerous interaction between cars and pedestrians. Why hasn't Hopkins?" Ignatowski wrote.

The team's preliminary research indicates that the state of Maryland has had one of the highest pedestrian fatality rates for a number of years. From 2007 to 2008, there were 197 total traffic deaths in the Baltimore-Towson metro area, with 19.4 percent of those deaths being pedestrians. This is almost double the national average of 11.8 percent, according to Transportation For America.

In addition, the United States Department of Transportation reported between 12 and 17 pedestrian fatalities per year from 2005 to 2009 in Baltimore City alone. In the past decade, there have been multiple pedestrian injuries and deaths specifically near Hopkins Homewood campus.

In 1999, a local resident died while jogging across Charles Street. Another noteworthy case occurred in 2004, when a freshman was hit while crossing Charles Street directly in front of the library. In 2009, another accident on St. Paul Street took the life of Miriam Frankl, a 21-year-old student. This past February, sophomore Nathan Krasnopoler was struck by a driver while riding his bike within the marked bike lane on University Parkway and passed away months later as a result of his injuries. The severity of these pedestrian accidents indicates a clear need for significant safety improvements, which the team is now trying to address.

"The project started in a civil engineering class, in which we were asked to design a steel structure. When we finished the project we approached our professor, Dr. Sangree, and asked her if she would work with us outside of class. She agreed and since then we have been meeting with her once a week to check in on how our project should progress," Kelly wrote. "We have also met with Dean Jones, the Dean of the engineering school and a civil engineer. Our Civil Engineering Design professors come from independent design firms, and they were able to introduce us to their colleague who works on strict pedestrian bridges, and he has been a big help."

The bridge's structure is designed to fit well with the architecture of the Homewood campus. The preliminary design is a precast concrete bridge spanning 150'-0" across Charles Street between 33nd and 34rd St. The West abutment would be located on the grassy hill between Mattin Center and the library, in front of the new Brody Learning Commons. The East side of the bridge would be between Charles Commons and The Charles Apartments, with access to the 2nd floor of Charles Commons.

Precast concrete products are manufactured at a plant, and exhibit high quality and uniformity. In addition, the manufactured sections are ready for transportation to the job site. The ease of precast concrete construction allows for a quicker construction process, leaving traffic minimally impacted.

"Prestressed concrete is a technology used in the last 50 years which uses cables that are essentially set in the concrete and pulled on to be tensioned and then released. This is used instead of steel to reinforce the concrete because concrete cannot hold tension and without these cables or steel the concrete will crack. It is a very popular method of construction — the new Brody Learning Commons uses a lot of prestressed concrete," Kelly wrote.

The team's engineering efforts include calculating the loads on the bridge deck, determining the stresses in the concrete and learning to select the best concrete shape for the bridge deck.

"Being engineering students is helpful because instead of simply proposing an idea we feel strongly about to the board, we can actually design the bridge in full and present a real solution," Kelly wrote.

In addition to providing safety for pedestrians, the team hopes that the bridge will be a connection between campus and residential facilities. "[The bridge is] important in two ways — for safety and for fluidity of campus. Right now the campus is very split between on and off campus life. This bridge will connect the two sides of campus. We see it as being a meeting spot for people before class or before going on to campus for other activities" Kelly wrote.

In addition to structural considerations, the team's focus include increasing project awareness and investigating how to encourage students to use the bridge, rather than crossing at street level.

"It is critical for students at Hopkins to work on science projects with the potential to affect our community, because it gives an opportunity to utilize the engineering principles we learn in the classroom in a practical way," Healy wrote. "This project has been an incredible opportunity to understand the many aspects that go into designing and planning of structures."