Hysteretic performance of square rotational friction damper

Abstract

The concept of square rotational friction damper is proposed in this paper. The hysteretic performance and influencing factors of the damper are comprehensively investigated through cyclic loading tests and numerical simulation. The energy dissipation performance and slip force model of the square rotational friction damper were experimentally tested, examining the effects of two factors: the materials of the friction pads and the pre-tension forces applied to the high-strength bolts. The numerical model was constructed and validated against the experimental results. A parametric study on square rotational friction dampers was performed through the finite element analysis approach, involving the variation of parameters such as the friction coefficient, bolt washer radius, and initial angle under cyclic loads. The results show that the square rotational friction dampers made of three types of friction pads exhibit strong energy dissipation capacity. The sliding force rises with the increase in pretension force of high-strength bolts. Brass friction pad dampers provide the largest sliding force, but non-asbestos composite friction pad dampers demonstrate the mostly steady sliding force. The sliding force of asbestos composite friction pad dampers decreases most severely with an increase in the number of hysteretic loops. The magnitude of the sliding force and the friction coefficient are linearly related. The slip force increases gradually as the radius of the bolt washer increases, but the increase is limited. When the initial angle of the damper is 90°, both the sliding force and the loading stroke reach their maximum values, resulting in the strongest energy dissipation capacity.