Yasunori Miyamori

Damage identification in a lightly reinforced concrete beam based on changes in the power spectral density

This paper deals with the detection of damage in a lightly reinforced concrete beam using dynamic measurements. An algorithm based on changes in the power spectral density (PSD) is presented. The algorithm is used to detect damage, predict the location and assess the extent of damage in the reinforced concrete beam. The method is based on the measured data on the beam after introducing some damage at salient locations. A tuneable piezoelectric actuator was used to produce additional peaks in the dynamic response of the system in the frequency domain. These additional peaks were adjusted over the frequency band by tuning the actuator. It was noticed from the results, that the PSD method detected the damage, determine the location and could monitor the increase in damage in the beam

Damage Identification for Civil Infrastructure Employing a Strain Energy Based Approach

The identification of structural damage is an essential goal of health monitoring for civil infrastructures. Damage of a structure reflects on a change of modal parameters, such as natural frequencies, mode shapes and modal damping. A method of damage identification for civil infrastructures based on strain energy is proposed in this paper. The method is described theoretically and applied to the experimental data from a steel bridge. Several damage scenarios were introduced to the members of the test structure. Experimental results show that the proposed approach may be successfully implemented to detect damage and to locate regions where damage occurred. This research also aims at establishment of experimental environment to enable the verification of applicability and the effective evaluation of the structural health monitoring (SHM) technology that uses the high performance sensor system on real bridges. The primary goal of the project is the development of test beds that meet wider requests for SHM experiments. Several steel bridges on an abolished railway in Hokkaido, Japan will be available for the establishment of the test beds. The test beds can be utilized by not only researchers of this project but also other researchers. The final goal of the project is international contribution by means of cooperative utilization of the test beds.