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Modern day masonry mortars rely on more than just standard constituents, which by definition include binder, aggregates and water. Due to different requirements imposed onto various types of masonry construction, ready mix mortar manufacturers and even masons and labourers on construction sites add certain additives to their mortar formulations. In this study, one standardized admixture is studied – an air entrainer/plasticizer (EN 934-3), coming in two forms – liquid and powder. It is applied to increase the air content and plasticity of cement-lime masonry mortar, formulated in volumetric proportions of 1:1:6 for cement, lime and aggregates. The dosage of admixtures is gradually increased starting with the manufacturer’s recommendations until the excessive air entrainment is achieved in order to determine the optimal dosage. Fresh mortar properties, including consistency, air content and bulk density are used to assess the enhancement of mortar influenced by the addition of the admixture, whereas compressive and flexural testing is performed at 7 and 28 days to monitor the disadvantages brought by reducing density. The results of this study reveal that the efficacy of a liquid admixture is better than that of a powdered air entrainer/plasticizer, albeit it being more difficult to use accurately. In both cases, higher dosage than manufacturer’s recommendations was required to reach satisfactory improvement of the fresh mortar structure, which resulted in a mixing water reduction, increased air content and reduced bulk density. That subsequently influenced the decreased strength, although optimally formulated mortars adhered to their strength class requirements.

According to EN 1996 Part 1-1, the flexural strength of masonry could be estimated based on information related mainly to the compressive strength of the mortar and the type of material of the unit. However, it is necessary to consider the impact of the interaction between components due to their physical characteristics, such as water absorption of the units and water retentivity of the mortar that may affect the bond between masonry components. Therefore, this paper evaluates the influence of the use of different types of mortar and units on the flexural strength parallel to the joints of masonry. For this, two types of mortar were considered: 1:1:6, and 1:0:5 (Cement: Lime: Sand), by volume. Regarding the units, two types of clay bricks of different geometric configuration (solid and frogged) were chosen. Thus, four combinations of units and mortar types were considered for the construction of the masonry wallets according to the guidelines indicated in EN1052-2. Flexural strength parallel to the bed-joints was tested according to EN1052-2, and compressive strengths of mortar specimens were controlled in accordance with EN1015-11 for the age of 90 days. In addition, characteristics of the units and water retentivity of mortars were also evaluated. The results showed that the compressive strength of the mortar is a significant factor if the failure occurs at the mortar bed-joint and not at the interface between components.

The University of Minho (UMinho) is aware of the relevant role of higher education institutions in the global challenge of sustainability. The integration of sustainability values into its strategy encompasses all the fields of its activity. Taking into account the growing importance of shared knowledge resources as a reliable basis for decisions during infrastructures life cycle, the UMinho is currently undergoing an important process of implementing a ‘Building Information Modelling’ framework (BIM). This paper briefly describes the implementation steps that are current towards such a goal, in particular in terms of facilities management aspects.