NON-DESTRUCTIVETESTING AS A NEW INTEGRATED
METHODOLOGY TO EVALUATE CHARACTERISTICS OF ROMAN
El-Banna .A .E
Dep. of Conservation, faculty of archeology, Cairo Uni.
Attiah .A.S.M 2
Supreme Council of Antiquities (SCA)
The traditional mortars in ancient buildings in El-Farama at north Sinai were used to provide uniform bearing between units and to bond individual blocks into a composite assemblage that will withstand the imposed conditions of loads. Formerly, we are lacking to data collection about the lime-based mortars concerning their mechanical properties and its relation with the stability of buildings as general. Perhaps, because of the difficulty of working with ancient mortars whether in situ or in laboratory testing according to the impossibility to have the required intact specimens which give comprehensive idea about the mechanical behavior of those mortars.
Nowadays, there are many devices which have been utilized in the field of ancient material science to solve all of mentioned problems we can use the traditional static testing methods to determine stability parameters such as compressive strength and modules of elasticity which represent the relationship between structural elements in old buildings.
By simulating the ancient mortars, testing samples consist of lime Ca (OH)2and different types of additives either (activated sand or pozzollana as natural ores) or (grinding fired brick as artificial one) which utilized in Roman era. So, an extensive research has been carried out by the authors regarding three precast mixture; the first group represent the type of air lime which formed from slaked lime, sand and wood charcoal. While the second group represent the hydraulic lime which formed from slaked lime, sand and fired bricks. The third group is represents the second type of hydraulic lime using a volcanic ash as a nature additive called pozzollana.
All three groups were subjected to tow different types of testing,acoustic test using longitudinal wave velocity, by measuring the time of transition of Vp across the samples according to the composition and quality of mortar. It has been stated that greater in strengthen is the hydraulic lime group with additives of pozzollana than the air lime group. Higher in strength due to the presence of pozzollana which react with calcium hydroxide producing very strong of a newly binders known as tri-calcium silicates
The second test depends on drill energy method to evaluate the mechanical behaviour of studied mortars by measure of the energy dissipated to make a small hole of 5 mm deep in the mortar. It has been stated that mechanical resistance of the mortar were better when the exceeding of lime proportion than additives.
(New integrated methodology, non-destructive methods, traditional mortar, Farama, Romanbuilding)
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