Experimental verification of flexibility difference method for locating damage in structures

✍ Scribed by A.K. Pandey; M. Biswas

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 871 KB
• Volume: 184
• Category: Article
• ISSN: 0022-460X
• DOI: 10.1006/jsvi.1995.0319

✦ Synopsis

A flexibility difference method for locating damage in structures is presented. This method is based on the estimation of changes in the flexibility matrix. First, with the help of an analytical model of beams, it is shown that a clear pattern exists for the changes in the flexibility matrix produced due to the presence of cracks. Next, the method is applied to several damage cases in three wide-flange steel beams. Damage in the beams is created by cutting through the beam using a saw. Experimental modal analysis techniques are used to estimate the natural frequencies and mode shapes for both the intact and the damaged beams. The measured natural frequencies and mode shapes are then used to estimate the flexibility matrix. Using only the lowest three modes, the flexibility difference method is successful in locating a 13 mm long saw cut in a 102 mm wide flange. The flexibility difference method is also successful in locating multiple damage locations in the beam.