Antonio C. Azevedo

  • This book discusses the effects of soluble mineral salts on ceramic brick masonry walls in Petrolina, a city in Pernambuco, Brazil, located 780 km from the ocean. To shed light on this phenomenon, the authors mapped the pathologies originating from the effects of soluble mineral salts and installed wells to monitor the underground water supply at five locations in the city where the phenomenon most frequently occurs. Further, they analyzed samples of soil, groundwater, and bricks affected by the phenomenon and measured levels of chloride in the atmosphere at these sites. The results obtained indicate that the pathological manifestations are influenced by the high levels of soluble salts observed in the soil and groundwater samples collected, and are not affected by chloride in the atmosphere.

  • This book offers a new calculation procedure of the structural behavior of grouped layout of silos, easy to use and with satisfactory responses.

    Groups of reinforced concrete silos are structures commonly used in the food industry, where it is usually necessary to separate the storage of different types and sources of grain.

    The grouped layout of silos has numerous benefits when compared with single-cell silos in which the emphasis is on creating further space for silage, normally referred to as interstice - a space formed between the edges of the group's cells. This economic benefit, on the other hand, raises a structural problem for the designer of this type of building, which is to assess the magnitude of bending moments and hoop forces due to the structural continuity of the walls in the interstice region of the cells. Bending moments assume extreme values exactly when the interstice is loaded and the other cells in the group are empty.

    To develop the formulation of the proposed analysis models, a parametric study was carried out that allowed the adequate consideration of the variables involved.

    The idea is to help professionals, engineers, industrials and academics involved in this advanced interdisciplinary field as a comprehensive guide for courses offered at different levels of learning (undergraduate and postgraduate).

  • This work presents an extensive experimental characterisation of two different ceramic brick blocks with different interface, at different heights, during the drying process. First, a laboratory characterization of the building material used (ceramic bricks and different mortars) is presented, showing their hygrothermal, mechanical and thermal properties, namely, bulk porosity and density, water vapour permeability, capillary absorption, retention curve, moisture diffusivity as a function of moisture content and thermal conductivity. Moreover, the moisture transfer in multi-layered systems was analysed in detail taking into account the interface contact between the building elements.

  • The knowledge of moisture migration inside building materials and construction building components is decisive for the way they behave when in use. The durability, waterproofing, degrading aspect and thermal behaviour of these materials are strongly influenced by the existence of moisture within their interior, which provoke changes in their normal performance, something that is normally hard to predict. Due to the awareness of this problem, the scientific community have per-formed various studies about the existence of moisture inside porous materials. The complex aspects of moisture migration phenomenon tended to encompass monolithic building elements, since the existence of joints or layers contributes to the change of moisture transfer along the respective building element that contribute to the change of mass transfer law. The presentation of an experimental analyses concerning moisture transfer in the interface of material that makes up masonry is described in such a way as to evaluate the durability and/or avoid building damages.

    In this work it was analysed, during the wetting process, the influence of different types of interface, commonly observed in masonry, such as: perfect con-tact, joints of cement mortar, lime mortar, and the air space interface. The results allow the calculation of the hygric resistance. With these results, it is possible to use any advanced hygrothermal simulation program to study the water transport in building elements, considering different interfaces and their hygric resistance.

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