Search

• The experimental test results reported are inedited. • Adhesion of the ceramic tiles on the masonry was satisfactory in all cases. • The idea of bonding ceramic tiles directly to concrete block surfaces is new. • The reader can benefit from knowing this idea and its bonding performance. The present work presents an experimental study on the behavior of ceramic tile rendering build on concrete block masonry walls loaded to compression failure. The walls were tested considering two different coating systems: a) direct application of adhesive mortar and lastly the ceramic tile; b) with cement plaster followed by the adhesive mortar and finally the ceramic tile. Four events were recorded: noise emission, plaster detachment, ceramic tile detachment and wall rupture. For both coating systems, the fracture loads were similar and ceramic tile detachment occurring at loads above expected service for residential buildings. [ABSTRACT FROM AUTHOR]

In this work, it describes the preparation of Titanium and Zirconium functionalized MCM-41 and subsequent chemical modification with nickel hexacyanoferrate. The obtained materials (MTiNiH and MZrNiH) were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-ray Dispersive Energy Spectroscopy (EDS), Porosity and Surface Area and Voltammetry Cyclic (VC). The cyclic voltammogram of MTiNiH and MZrNiH modified graphite paste were sensitive to isoniazid concentrations. The MTiNiH modified graphite pulp electrode showed an analytical curve with a linear response of 2.0 × 10–5 to 5.0 × 10–4 mol L−1 and detection limit of 6.12 × 10–6 mol L−1 and MZrNiH modified electrode showed an analytical curve with a linear response of 3.0 × 10–5 to 3.0 × 10–4 mol L−1 and detection limit of 1.66 × 10–5 mol L−1. After catalytic electro-oxidation of isoniazid, a study of the main interferents was performed and the recovery of isoniazid in a synthetic urine sample was also evaluated. The MTiNiH and MZrNiH materials stand out for presenting good detection limit and recovery efficiency in real samples. Therefore, these materials can be considered is a strong candidate for the construction of electrochemical sensors for quick and easy detection of isoniazid. [ABSTRACT FROM AUTHOR]

• The results of the evaluation of the use of polishing residues on concrete floors prove to be viable. • The reuse of polishing residues increases the mechanical strength of Portland cement. • Reusing polishing wastes could be a win environment impact. The objective of this work is to analyze of reusing concrete floor polishing waste (CFPW) as an additional material to cementitious compounds, reducing at the same time both the consumption of Portland cement and the environmental problems. Mortars and pastes were produced with CFPW additions (4%mass up to 12%mass) and were characterized in terms of mechanical properties, chemical composition, and thermal analysis. The results of the thermal analysis showed that the moisture carbonation increased as the CFPW %mass increased. The results of the mechanical compression tests showed that the addition of CFPW increases the compressive strength of mortars. The conclusion is that adding CFPW to cementitious compound is feasible in order to reduce the consumption of Portland cement and preserve the environment. [ABSTRACT FROM AUTHOR]

The evaluation of the durability of materials and of construction systems involves the identification of several agents that attack the environment, in tropical countries, such as Brazil, climatic factors tend to intensify the problems related to the durability of constructive elements. The façade of buildings are the ones that suffer the most from climate change, as they oscillate between large exposures of solar radiation and cooling, a function exerted by rainfall. It is proposed in this study comparisons between results of tests of resistance to heat and thermal shock in façades of buildings, in which it is described in the performance standard - NBR 15575-4 (ABNT, 2013). Most of the results were positive in some test specimens, that is, in the tests of the specimens in question, it was possible to attend to the standard, however a revision of the test method established in the standard is proposed, so that the normative details can meet with more precise the elements tested. [ABSTRACT FROM AUTHOR]