Evaluation of the Seismic Behaviour of an Inca Stone Wall Using Rigid Body Dynamic Methods

Peru has around 7 360 prehispanic archaeological monuments [1] according to the Ministry of Culture of Peru. These structures, built with irregular shapes and variable configurations, are very complex to evaluate. Unfortunately, some of these constructions are in poor conservation state due to external factors such as earthquakes, soil settlements or human activity [2]. For example, some Inca culture stone walls from archaeological sites such as Puka Pukara, Sacsayhuaman, Huchuy Qosqo and Chinchero present visible damage directly associated with previous earthquakes [3]. In this research, the dynamic response of an Inca stone wall from Sacsayhuaman is evaluated using rigid body dynamics in Abaqus [4]. Sacsayhuaman archaeological site is made up of enormous retaining walls with large carved stones and dry joints. The stones were modelled with their irregular shapes as rigid bodies and their interactions by means of interfaces with normal and shear stiffness. All mechanical properties were adequately calibrated based on experimental tests and literature review. The results confirm that the use of rigid body dynamic methods can help to evaluate the seismic performance of stone structures and to identify the most probable collapse mechanisms during a seismic event.