Avaliação do uso do DCP em areias para controle da capacidade de carga em fundações diretas e controle de compactação de aterros

This work presents results of field and laboratory tests using a Dynamic Cone Penetrometer, DCP. The tests were performed in order to evaluate the use of the equipment in sand for the control of bearing capacity of shallow foundations and fill compaction. For shallow foundations, the laboratory tests were conducted on sand placed in a metallic mould by the method of sand pluviation. Although the results show the inability to reproduce field conditions in the laboratory it was possible to verify the ability of the DCP to identify less resistant soil layers. The DCP tests for the analysis of compaction control were performed in a strong box with inside dimensions of 1,40 m x 1,40 m and 0,70 m in height. The soil layers were compacted with different densities though the use of a vibrating plate in order to obtain correlations between penetration index, DPI, and soil relative density. Other tests were also conducted to assess the influence of soil moisture on tests results. Among other findings, the results showed the great potential for the use of DCP to control the compaction of sand fills

Caracterização de escovas de grafite e avaliação do seu desempenho em função da microestrutura

The electric can be converted into thermal, luminous, electromagnetic, and also in mechanical energy. In this context the electric engines plays a fundamental role, specially that they work very below of its nominal capacity, with consequent decrease load density. In industrial environment, these characteristics of work of DC engines had also generated an extreme consumption of coal brushs and attack in the commutator reducing the useful life of the engine and increasing maintenance demand and cost. The general objective of the present work is to study the influence of the granulometry of the coal brush used in DC engines with the resistance to the consumption of the same ones, as well as in the performance presented by the commutator of the engine. Additionally, determining the measurable and not measurable profits when the brush used is adjusted to the application. The brushes had been produced by an industry of the sector and tested in industrial environment to evaluate their performance and consumption. Preliminary results evidence a substantial improvement in the performance of these brushes in function of its microstructure and the application in which it is used