Faculty of Engineering, University of Porto – Portugal, DEC, Gequaltec

Reflecting the recent European Directives concerning building energy efficiency, two new envelope type masonry systems were developed in Portugal. The purpose was to design large single leaf external walls with thermal resistance according to Portuguese requirements, and enough mechanical capacity to be used structurally in small buildings. The masonry systems are based on large lightweight concrete units and large clay units, bedded on mortar strip joints. Although from a mechanical point of view, EC6 provides a methodology that allows one to estimate the main mechanical characteristics of masonry, tests were carried out to evaluate the more relevant mechanical properties of units and masonry. This paper describes the mechanical experimental evaluation of these units and masonry systems. Laboratory tests were undertaken, namely masonry compressive and shear according to standards EN 1052-1, EN 1052-3 and ASTM E 519. The test results evaluated the shear strength, compressive strength, shear modulus and modulus of elasticity. A comparison is presented between the experimental results and the default values given by EC6 methodology, and a few differences are pointed out. Based on the experimental results, expressions are suggested to allow for a proper evaluation of the mechanical properties of this kind of masonry systems.

Key words
mechanical performance; single leaf wall, lightweight materials, laboratory tests, EC6