Brazilian test method

In this paper, amodified SHPB technique and Brazilian test method is presented to test the dynamic tensile strength of coal, shale and sandstone rock samples. Totally four different kinds ofloading rate were tested to investigate the relationship between tensile strength and dynamic loading. Static test results are also presented for the comparison. 

Methods to determine compression behavior can be either static (dead load) or based on constantly increasing compression. Several methods for the determination of volume-reduction mechanisms due to compression or compaction have been presented in the literature the most relevant ones are described in the following sections. Compression mechanisms can be approached from different tests such as the Brazilian test, uniaxial confined compression test, cubical triaxial tester, HHP method, and the unconfined... 

Different commonly used compression characterization methods have been demonstrated the Brazilian test, the confined uniaxial and unconfined compression test, and the flexible boundary cubical triaxial test. The HHP method appears as a new and promising possibility within the traditional compression methods. In HHP, higher pressure gives higher bulk density however, beyond a critical given pressure, the final compressed bulk density remains constant (ultimate bulk density). Further studies will determine whether this concept can be included as a quality descriptor in the specification data sheets of commercial food agglomerates. 

ABNT (2011), ABNT NBR 15708-1 Petroleum and Natural Gas Industries - Pultruded Shape. Part 1 Materials, Test Methods and Dimensional Tolerances, Rio de Janeiro, Brazilian Association of Technical Standards [in Portuguese],... 

Brazilian Test. A method for the determination of the tensile strength of concrete, ceramic, or other material by applying a load vertically at the highest point of a test cylinder or disk (the axis of which is horizontal), which is itself supported on a horizontal plane. The method was first used in Brazil for the testing of concrete rollers on which an old church was being moved to a new site (cf BRITTLE-RING TEST). 

Pepin Lehalleur(Ref l,p 470) described Brazilian pyrotechnics and Da Roca Lima(Ref 4) reviewed the characteristics and methods of testing modern expls... 

A reversed-phase liquid chromatographic method was developed for simultaneous determination of carboxylic acids, phenolic compounds, and SA in white wines (84). The diluted samples are injected into a Spherisorb ODS-2 column with a gradient of sulphuric acid (pH 2.5)/methanol as mobile phase. A diode array detector is used, set at 210 nm for carboxylic acids and altered to 278 nm, during the run, for phenolics and SA. The identification of compounds is based on retention time and UV spectra. Some cleanup methods (Sep-Pak C18 and an ion-exchange column) were tested and did not improve the results. The analysis was considered simple, with no sample preparation. Application of this method was illustrated by analyses of Brazilian Welchriesling wines (84). 

The issues of method validation and assessment of measurement uncertainty in the determination of potentially toxic trace elements in rice are of permanent interest for the scientific community. In this context, the sources of uncertainty associated with the determination of Cd, Cu, Pb, and Zn have been recently estimated in rice through an interlaboratory comparison [30]. Four Brazilian laboratories participated in the proficiency test. The analytical technique used were FAAS, ET-AAS, and ICP-AES. The rice samples were supplied by the Institute for Reference Materials and Measurements (IRMM), Joint Research Center of the European Commission, within the scope of the interlaboratory comparison International Measurement Evaluation Programme (IMEP) 19 Trace Elements in Rice (see also Chapter 7 in this book). Three out of the four laboratories reported values close to the reference values. It was emphasized that, in order to establish a reliable uncertainty budget, all significant sources of uncertainty should be identified. 

The mechanical properties of concrete evaluated were the compressive and tensile strengths, at 7 and 28 days. Each result represents an average of 3 specimens. The compressive strength tests where performed according to the NP EN 12390-3 [16], where as the tensile strength test adopted was the Brazilian method, according to NBR 7222 [17], which determines the tensile strength by diametrical compression of specimens. 

Mahabadi O.K., Grasselli G., Munjiza A. 2009. Numerical modelling of a Brazilian disc test of layered rocks using the combined finite-discrete element method. ROCKENG09 Proceedings of the 3rd CANUS Rock Mechanics Symposium. Paper 4148. Toronto. 

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