MSE Seminar Series: I. Cevdet Noyan
Friday, October 7, 2016
Room 2108, Chemical and Nuclear Engineering Building
I. Cevdet Noyan
Chair, Applied Physics and Applied Mathematics
Professor, Materials Science and Engineering, and Earth and Environmental Engineering
Measurement of Stress Partitioning in Suspension Bridge Cables
Suspension bridges are essential elements in the transportation network of major
metropolitan areas. Some of these bridges have extended service lives that span over 100 years. The main cables, with thousands and thousands of steel wires compacted together, are the most crucial element for the overall safety of such structures in the sense that, if a cable fails, the entire bridge may collapse. Correctly assessing the current or remaining strength of a main cable in use is a necessary but challenging task. Very limited experimental data is available in the literature and the current experimental techniques are unreliable. From a numerical standpoint, the problem is difficult due to geometric, material and contact nonlinearities. We have used neutron diffraction to measure partitioning of applied tensile load between the inner and outer
wires of seven-wire parallel and quasi-parallel wire strands. Our results indicate that mechanical interference and friction mechanisms have similar contributions to the load transferred to fractured wires, and both mechanisms should be included in analytical or numerical formulations of strain partitioning in quasi-parallel wire cables. The implications of our findings on bridge construction and maintenance will also be discussed.
This Study was funded by NSF Structural Materials and Mechanics Program through Award
CMMI – 1233885.