Наредни састанак Семинара биће одржан у среду, 6. децембра 2017. у сали 301ф Математичког института САНУ са почетком у 18 часова.
Предавач: Si Mohamed Sah, Danish Technical University
Наслов предавања: ASSESSING BOLTED JOINTS TIGHTNESS WITH MEASURED NATURAL FREQUENCY
Апстракт: Structural health monitoring techniques based on vibration measurements have been receiving large attention in the last decades, in particular techniques used for estimating bolted joints tightness and detecting loosened bolts. Due to the exposure of bolted joints to external forces, the bolts may loosen and therefore affect the healthy functioning of the bolted structure. In this work, a technique is proposed to assess the level of bolt tightness and to quantify the tension based on the measured natural frequencies. An experiment is performed on two structure specimen where each one is clamped with a bolt. The excited natural frequencies are recorded as the bolts are gradually tightened. The measured frequencies trends were described by a one dimensional beam model with elastic supports. The sensitivity of the measured transverse frequency showed the reliability of this frequency-based technique in assessing bolt tightness. This technique can also quantify the bolt tension using the analytical model, which gave an excellent agreement with the experimental data for high bolt tension.