An investigation of the effects of mass distribution on pounding structures

作者：Cole Gregory^*; Dhakal Rajesh; Carr Athol; Bull Des

来源：Earthquake Engineering & Structural Dynamics, 2011, 40(6): 641-659.

DOI：10.1002/eqe.1052

• distributed mass
• pounding
• equivalent lumped mass
• coefficient of restitution
• pounding force

The effects of diaphragm mass distribution are investigated for building pounding. Elastic diaphragm-to-diaphragm collisions are explained by considering the total momentum over the length of each diaphragm at three critical instants during collision. Expressions for collision force and collision duration are produced, providing additional information about the collision process. Equations for the post collision velocity of each diaphragm are produced and are found to appreciably differ from conventional impact-momentum equations under certain conditions. The change in post collision velocity is found to be dependent on the ratio of the axial periods of free vibration of the two diaphragms and the ratio of their masses. An equivalent lumped mass model is proposed and assessed against simplified distributed mass models with numerical modelling of two two-storey buildings. Finally, a new parameter is introduced to represent the plasticity of an inelastic collision between the two distributed masses. This paper highlights the significant influence that diaphragm mass distribution may have on the analysis of pounding structures.

• 出版日期2011-5