LAUSR

Abstract In this article an overall procedure is proposed, for the numerical investigation of the structural response of ancient monuments made of megalithic stones. The procedure is implemented on the middle temple of the Mnajdra Megalithic structure, listed as UNESCO World Heritage and regarded as one of the oldest structures from early civilization dating back to about the 4th millennium BC. First, the geometry of the structure is obtained from a point cloud using terrestrial laser scanning. To investigate and estimate the material properties of the structural system, parametric eigenvalue analysis is conducted using the finite element method and results are compared with experimental data from ambient vibration sensors applied to the same structure. The structural response of the system is then evaluated, using nonlinear finite element analysis. Variation of unilateral, frictional contact conditions between megaliths in a preceding analysis step may influence the eigenvalue analysis which follows, indicating the importance of the proper consideration of contact conditions, on the response of the structure. An old collapse in a part of the structure is also reproduced by the numerical model. The proposed scheme, which combines numerical analysis and experimental vibration output to derive structural properties of the monument, can be used in similar structural systems, consisting of multi-body megalithic stones.