Maintenance of existing steel infrastructures: Evaluating remaining lifespan

Research

Published: November 12, 2014

The maintenance of existing steel infrastructures such as bridges is vitally important to ensure the safety of our society. Ongoing monitoring, inspection, and evaluation are key processes in these maintenance programs. However, it is difficult to evaluate the actual remaining capacity and lifespan of infrastructures from current inspection methods.

Now, Eiichi Sasaki and his colleagues are aiming to develop efficient maintenance systems especially for steel structures. In the development of such a system, the quantitative evaluation of the remaining capacity of structures is one of the most important variables to ascertain.

The team investigated the effects of various types of damage on steel bridges and developed an evaluation method for efficient maintenance systems. They conducted real-scale experiments and detailed numerical modeling to uncover the variety of damage patterns in actual structures.

The investigations by Sasaki's team revealed that in both shear, and shear-bending, cases, the ratio of width-thickness ratios between damaged and un-damaged regions is the governing parameter to determine the remaining capacity.

Their final evaluation method proposes using this new governing parameter as a useful method of interpreting results from the inspection of steel bridges.

Figure1.

Figure2.

Actual damage on steel structures, alongside output damage modes of steel girder ends from the model developed by Sasaki and his team at Tokyo Tech.

Reference

Authors:	Nauman Khurram, Eiichi Sasaki, Hiroshi Katsuchi, and Hitoshi Yamada.
Title of original paper:	Experimental and numerical evaluation of bearing capacity of steel plate girder affected by end panel corrosion.
Journal, volume, pages and year:	International Journal of Steel Structures 14, 659-676 (2014).
Digital Object Identifier (DOI):	10.1007/s13296-014-3023-8

Authors:	Nauman Khurram, Eiichi Sasaki, Hiroshi Katsuchi, and Hitoshi Yamada.
Title of original paper:	Analytical demonstrations to assess residual bearing capacities of steel plate girder ends with stiffeners damaged by corrosion.
Journal, volume, pages and year:	Structure and Infrastructure Engineering 10, 69-79 (2014).
Digital Object Identifier (DOI):	10.1080/15732479.2012.697904

Authors:	Nauman Khurram, Eiichi Sasaki, Hiroshi Katsuchi, and Hitoshi Yamada.
Title of original paper:	Finite element investigation of shear capacity of locally corroded end panel of steel plate girder.
Journal, volume, pages and year:	International Journal of Steel Structures 13, 623-633 (2013).
Digital Object Identifier (DOI):	10.1007/s13296-013-4004-z

Further information
Associate Professor Eiichi Sasaki
Department of Civil and Environmental Engineering
E-mail sasaki.e.ab@m.titech.ac.jp
TEL +81-3-5734-3099 FAX +81-3-5734-3577