Investigation of the structural behaviour of Megalithic Mnajdra Monument.

Abstract

The Maltese megalithic temples are regarded as one of the oldest structures from early civilization dating back to about the 4th millennium. These megalithic structures provide valuable information due to their complexity of geometry and the way they were constructed, and they also serve as one of the main tourist attraction areas in the Maltese islands. The areas in which these megalithic structures are found have been listed as UNESCO World Heritage Sites. In this study, the structural behaviour of the middle temple of the Mnajdra Megalithic temple is investigated. First, the geometry of the temple was obtained from a cloud of points using radar-laser scanning. The mechanical material properties of the megaliths and soil were obtained from published experimental research on similar monuments. A finite element model was created whereby nonlinear contact mechanics was applied since unilateral contact between parts is the major stress-transfer mechanism. Simulations from eigenmode analysis show various natural frequencies and shape modes of the monument which can be validated from experimental data obtained from an ambient vibration monitor. Results obtained from structural analysis show the major stress transfer points between the megaliths, the response of the structure under selected loading scenarios as well as potential collapse mechanisms.