COMPATIBLE DILATION LIMITS OF MASONRY JOINT MORTARS

摘要

The effects of joints in non-plastered masonry on the behavior of the masonry and on damage processes have been investigated in various studies, mostly in relation to the permeability of the joint mortar. The typically observed damage to some water-sensitive stone in ashlar masonry has usually been explained as a consequence of increased moisture and possible frost damage in the vicinity of impermeable mortar joints. This article presents an analysis of the stresses in an ashlar masonry model due to variations of temperature and solar heating of the stone/mortar systems. It is clearly shown that temperature fluctuation effects can generate significant stresses in the interface layers in contact between stones and mortar joints. The pattern of the elevated stress fields well-corresponds to the pattern of damage to ashlar masonry observed in practice. The thermal expansion analysis is modeled by a three-dimensional finite element model.