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BUILDING MATERIALS, DETERIORATION PROBLEMS AND
STRUCTURAL CONSERVATION OF MACEDONIAN TOMB OF DERVENI
THESSALONIKI GREECE
SPATHIS PANAGIOTIS1*, CHARALAMBAKIS NICOLAS2, CHRISTARAS BASSILE3
(1*) Professor, Aristotle University of Thessaloniki, School of Chemistry,
e-mail:[email protected]
(2) Professor, Aristotle University of Thessaloniki, School of Civil Engineering
(3) Professor, Aristotle University of Thessaloniki, School of Geology
ABSTRACT: From the excavations at Derveni area Thessaloniki, large constructions
of a Macedonian tomb built during the 4th century B.C., were found. The problem of
the conservation of the mud brick, the main building material of these structures, is
severe and condition to select an effective preservation method is the knowledge of
the composition and properties of the material, as well the processes contributing to
the deterioration of the structures. A study of the mineralogical and chemical
composition as well as the physical and mechanical properties of the material was
carried out and from the results it follows that it consists of a mixture of silt and sand.
The material of the walls is similar to the surrounding ground and is mainly composed
of quartz, feldspars, muscovite, plagioclase and calcite while the arches have a calcite
composition. The physical and mechanical properties and characteristics, related to
the weathering resistance of mud brick were determined: texture, hardness, strength,
bulk density, porosity, physical moisture, water absorption, sonic velocity. The results
of the above measurements showed that the material is relatively stable and strong but
sensitive to deterioration caused mainly by water and rain erosion. A study of the
structural stability of the monument was carried out. From the results of the
displacement analysis of the structure, it derived that a complex destabilizing
mechanism was manifested, due to the combined effect of the change of static loading
caused by the excavation, the dynamic loading and the influence of rain water, which
enhances the lateral active earth pressures. Specific measures of structural
conservation are proposed concerning the reinforce of the different parts of the
structure in relation to the continuation of the excavation works, the repair and the
final remove of the counterfort walls.
Keywords: mud brick, composition, properties, weathering resistance, structural
stability