Ε21

The behaviour of masonry structures is examined when they are subjected to static forces and seismic actions. Initially, the mechanical characteristics of the constituents (mortar and natural stone or stone) are presented. Next. the behaviour of typical structural elements made of masonry is examined when they subjected to dominant either in-plane or out-of-plane state of stress. This is done by presenting the dominant limit-states and the corresponding modes of failure. The corresponding principles of current design procedures are outlined towards defining the most important bearing capacities of typical structural elements. The ways and the limitations that these design procedures can be linked to cultural heritage structures are also presented together with the relevant laboratory or in-situ capabilities. Finally, the behaviour of masonry structures when subjected to static loads and seismic actions is examined by portraying the transfer of the relevant forces to the ground. Typical damage to cultural heritage masonry structures when subjected to static loads and seismic actions are presented and discussed. The methodology for assessing the demands that arise to the primary masonry structural elements is also described employing numerical methods.

Course description

CONSTITUENT MASONRY MATERIALS: The mechanical characteristics of the mortar and masonry units (made of clay or natural stone) are presented together with their interaction. This behaviour is examined for simple loading conditions employing laboratory capabilities. The behaviour of the mortar and masonry units at their contact interface is examined when simple assemblies are subjected to a combination of normal and shear state of stress at such an interface. The modes of failure and the relevant failure criteria are presented together with the corresponding laboratory capabilities.

MASONRY STRUCTURAL ELEMENTS-1: The in-plane and out-of-plane behavior of masonry structural elements is examined when the structure which they belonged to is subjected to combined static loads and seismic actions. The corresponding limit states are described due to stress fields that include either in-plane normal and shear stresses or out-of-plane normal and flexural stresses. The corresponding failures modes are also presented and linked with the mechanical behaviour of mortar and masonry units and their interaction at the mortar joints. These modes of failure are next combined with relevant failure criteria. The limit-state behaviour to in-plane axial compression, shear, diagonal tension or out-of-plane flexure with compression is presented together with the corresponding laboratory testing. Finally, the influence of wooden or metallic inserts is also presented

MASONRY STRUCTURAL ELEMENTS-2:  The basic principles of current procedures for the design of structural masonry elements are presented. The relevant methodology of defining the bearing capacity of masonry structural elements for the in-plane and out-of plane demands resulting from load combinations is also presented. The application and its limitations for using such current design procedures for masonry cultural heritage structures are also presented. Laboratory and in-situ methodologies and procedures for measuring the masonry mechanical properties towards quantifying the bearing capacity of masonry structural elements is also examined employing destructive or non-destructive testing and simple or complex laboratory or in-situ procedures.

MASONRY STRUCTURAL SYSTEMS:The behaviour and the response of masonry structural systems is examined when subjected to static loads and seismic forces together with the transfer of the resulting seismic forces and the development of in-plane or/and out of plane demands to the structural elements or their connections. The importance of the behaviour of the structural system as a whole is described underlining the connections of the vertical structural elements between each other and with the floors, the roof and the foundation. The methodologies for finding the damands that arise at critical areas together eith the formation of simulations of the behaviour employing laboratory or numerical procedures are also presented. The ways these demands appear to form at the level of the structural elements is also presented together with the ways that such results can be utilized to check the performance of this type of structural formations.