The 15th Global Conference on Materials Science and Engineering (CMSE 2026)

Abstract: Accounting for rocking motion in structural design can enhance seismic resilience by improving a structure’s capacity to resist earthquake-induced loads. This study reviews the historical development of rocking motion analysis, addressing both methodological approaches and practical applications. Subsequently, a framework is presented for implementing the Discrete Element Method (DEM) to analyse the rocking behaviour of a rigid body using the open-source software Yade. The simplest and most economical approach - modelling the entire building as a clump of lumped masses has been adopted. The length of the building is assumed to be twice its width, and the number of stories - eight, which is typical for a Bulgarian reinforced concrete residential building. The model was subjected to three levels of ground motion with peak ground velocity (PGV) of up to 3.5 m/s along the width, while for each PGV level, a ground motion along the length of 50% the PGV or 100% the PGV was applied. A case without a ground motion along the length was also considered. In addition, the influence of the vertical component of ground motion acting together with the horizontal components was investigated. The rocking response of the building and its dependence on the intensity of ground motion were examined. The influence of the multi-directivity of ground motion on the rocking response was assessed in terms of the onset of rocking and the width of the separation gap.

Keywords: Rocking motion, rigid body, discrete element method

Biography: Radan Ivanov is a Professor at the National Institute of Geophysics, Geodesy and Geography, Bulgarian Academy of Sciences, specializing in Earthquake Engineering and Structural Mechanics. His research focuses on strong-motion seismic monitoring, the processing and analysis of seismic and experimental vibration data, and the dynamic behaviour of structures under earthquake excitation. He earned his PhD at Kobe University, Japan, where he also conducted postdoctoral research and contributed to seismic engineering studies, including seismic instrumentation, earthquake-record analysis, and post-earthquake building investigations. His academic and research experience spans numerical methods in structural mechanics, discrete element analysis, and experimental assessment of structural dynamic characteristics using ambient vibrations. He has authored 116 scientific publications and participated in 17 research and applied-science projects.