Estimation of dynamic properties of traditional wooden structures using new bolt sensor

Abstract

Dynamic properties of traditional wooden structures are estimated from forced vibration test performed on a prototype constructed for this purpose. The prototype corresponds to a framed wooden construction with traditional connections between columns and beams without nails and with wedges inserted into joints to fix them. To verify the applicability of a new type of piezoelectric bolt sensor the test series were performed using also commercial accelerometers and laser displacement transducer for comparison. The new bolt sensor is intended to be used for structural health monitoring of important and small structures like historical shrines or other small historical buildings. Bolt sensors were installed in selected frame joints and changes in the voltage signal were detected when the prototype is subjected to dynamic excitation. The response of the new sensor is comparable with that obtained by high precision commercial accelerometers and laser displacement transducer. In addition the dynamic response of the structure and the response of the bolt senor were verified analytically using finite element method. For analytical modeling semi-rigid joint is used where the moment rotation relationship is specified for each beam end. The research serves also to calibrate the analytical model by using experimental results obtained from forced vibration test.