Various monitoring sensors have been used for the monitoring and damage prediction of structures. Piezoelectric and optical fiber sensor that are required housing for the field applications are used widely. The voltage change of piezoelectric for the steel girder is used for damage prediction. The inspection and monitoring for safety of crane is not easy because it is located in high level and the operation should be stop for the inspection. The constant input load by moving the crane girder with constant speed was used instead of ambient vibration. In this test, wireless monitoring system using LAN is tried for the long distance measurement. The objective of this paper is to present the dynamic measurement results to identify the potential damage of steel beam using piezoelectric sensor. Cantilever beams, a simply supported beam with bolted splice, and actual crane girder have been chosen for the test. FFT method was used for the damage identification. This output-only dynamic test is likely applied to the top crane to monitor the damage.
Concrete may the economical material available for buildings and civil structures due to various important its properties such as high compressive strength, wear resistance, abrasion resistance and durability. The most disadvantages of concrete structural elements are its cracks in flexure. Visual inspection is difficult and provides little detailed information in crack conditions. Recently, a new trend, called smart concrete or structure, has been emerged using various technologies for monitoring of crack conditions of concrete. A method designed to monitor or characterize the crack conditions in concrete beams in flexure using polymerbased composite sensors is conducted in the present work. The embedded polymer-based composite sensor shows a potential to evaluate the conditions of concrete's cracks in beams under flexural loading such as initial and critical crack conditions, using data acquisition system.