Nabil F. Grace Ph.D, PE
Chair and University Distinguished Professor, Civil Engineering Department
Lawrence Tech Engineers Dedicated Bridge with a Brain
Southfield, Mich. - Electronic sensors embedded in the Bridge St. bridge in Southfield, make it possible for engineers to monitor the performance of the unique bridge in a national study funded by the National Science Foundation and exclusive to Lawrence Technological University. The first of its kind in the world, one lane of the concrete bridge is reinforced with pre-stressed carbon-fiber reinforced polymers (CFRP), and the other is reinforced with traditional steel.
Nabil Grace, professor and chair of civil engineering at Lawrence Tech, collaborated with engineers at Hubbel Roth & Clark, the City of Southfield and Japanese manufacturing firms to research, coordinate material testing, and determine construction standards for this unique bridge design.
The revolutionary rods are made from carbon fibers the diameter of a human hair. CFRP strands are woven together and encased in epoxy to optimize bridge durability. The lightweight, yet extremely durable carbon-fiber rods are far less susceptible to corrosion than steel cables, shows Grace's research.
By dialing into the bridge's computer daily, Grace, his students and the City monitor the bridge's performance, and compare it to that of the conventional steel-reinforced span. The ongoing study, using sensors installed in the carbon-fiber reinforced section of the bridge, determines the long-term benefits of CFRP over conventional steel reinforced bridges.
The $8.5 million project was funded by the Federal Highway Administration and the City of Southfield. The bridge opened for traffic Dec. 2001 and will be dedicated at special ceremonies May 8, 2002 at 10 a.m.
Because it's incredibly strong and virtually impervious to water, salt and extreme temperatures, CFRP may be applicable to other types of construction: for balconies, particularly on buildings near the ocean; strengthening older buildings; in hospitals where steel reinforcement can interfere with high-tech equipment; for underground applications and for highway pavement reinforcement.
Celebrating its 70th anniversary, Lawrence Technological University offers nearly 50 undergraduate, master's and doctoral degree programs in Colleges of Architecture and Design, Arts and Sciences, Engineering, and Management. Lawrence Tech pioneered the offering of day and evening classes, and now has a growing number of weekend programs. Lawrence Tech also is home to the Advanced Technology Academy, a charter high school offering a challenging curriculum closely linked to the University's academic mission.