In the north of the province of Santa Fe, especially in the forest wedge, Lower Submeridionals and Occidental Domo, there are more than three million head of cattle, where one of the main determinants of production is the irregular quality of groundwater For the watering of the hacienda. The fluctuation between dry and wet hydrological scenarios has a direct impact on production, where not only the free water table, which is the only available water, varies, but also the chemical quality of the water. In collaboration with the INA, the Government of Santa Fe and UNL Research Centers, INTA has developed research and transfer demonstration units in the fields of producers and experimental units of the Institution, designing and proposing different technologies that are consensual with the Producers in the management of rainwater supplemented with the underground. 3 water systems were implemented with different ways of using rainwater with groundwater, systematizing terrain to guarantee access and recharge of the free aquifer, with pumping mechanisms using renewable energy and with suction systems that do it in the part Surface of the aquifer, where all converge to a central mixing tank, to ensure that all animals take water with the same chemical quality, whatever the place of grazing. Since 2011 the variables of interest are monitored, where the premise is to have controlled the salinity of the water in the central mixing tank and that its variations throughout the year are gradual, since this maximizes livestock production. This is visualized in each of the three systems and, fundamentally in the central mixing tank, where the quantity, quality and opportunity during the year clearly show very positive results in the place studied.

En el norte de la provincia de Santa Fe, especialmente en la Cuña Boscosa, Bajos Submeridionales y Domo Occidental, se encuentran más de tres millones de cabezas de ganado vacuno, donde uno de los principales condicionantes en la producción es la irregular calidad del agua subterránea para el abrevado de la hacienda. La fluctuación entre escenarios hidrológicos secos y húmedos repercute directamente en la producción, donde no solo varía el nivel freático del acuífero libre, único aprovechable, sino fundamentalmente la calidad química del agua. El INTA, articulando con el INA, con el Gobierno de Santa Fe y con Centros de Estudio de la UNL, ha concretado unidades demostrativas de investigación y transferencia en campos de productores y unidades experimentales de la Institución, diseñando y proponiendo distintas tecnologías consensuadas con los productores en lo que hace al manejo del agua de lluvia complementada con la subterránea. 3 Sistemas de Aguadas se concretaron con diferentes maneras de aprovechar el agua de lluvia con el agua subterránea, sistematizando terrenos para garantizar el acceso y recarga del acuífero libre, con mecanismos de bombeo mediante energía renovable y con sistemas de succión que lo hacen en la parte superficial del acuífero, donde todos convergen a un tanque central de mezcla, para garantizar así que todos los animales tomen agua con la misma calidad química, cualquiera sea el lugar de pastaje. Desde el año 2011 se monitorean las variables de interés, donde la premisa es tener controlada la salinidad del agua en el tanque central de mezcla y que sus variaciones a través del año sean graduales, ya que esto maximiza la producción ganadera. Esto se visualiza en cada uno de los 3 sistemas y, fundamentalmente en el tanque central de mezcla, donde la cantidad, calidad y oportunidad durante el año evidencian claramente resultados muy positivos en el lugar estudiado.

Abstract Over the last few years, comprehensive management programs for the diagnosis and prognosis of alkali-aggregate reaction (AAR) in aging concrete structures were developed in North America, based on a series of laboratory test procedures. Although promising, these lab-procedures presented several parameters whose impacts were not completely understood, which significantly reduced their applicability for the appraisal of deteriorated concrete structures in service. In this context, it has been suggested that two lab-tools, the Stiffness Damage Test (SDT) and the Damage Rating Index (DRI) could reliably assess the condition of concrete affected by AAR. This paper presents the condition assessment of 25, 35 and 45 MPa AAR affected concrete specimens incorporating fine and coarse reactive aggregates and presenting different distress degrees (i.e. expansion levels from 0.05 to 0.30%) through the use of an innovative multi-level approach. Results show that both SDT and DRI are suitable for assessing damage in AAR affected concrete through their output parameters. Yet, they present a complementary character, which illustrates the need for a multi-level approach.

Existem muitos métodos de ensaio de laboratório utilizados na prevenção da reação álcali-agregado, entretanto, até o momento não existe consenso no que tange confiabilidade e eficiência destes. Este trabalho apresenta a tentativa de desenvolvimento de um novo método de ensaio acelerado denominado ABCPT (método acelerado brasileiro de prismas de concreto), com o intuito de que este possa, de maneira rápida e confiável, analisar e classificar agregados mediante a sua potencial reatividade em laboratório. Para o desenvolvimento desta pesquisa, foram utilizados seis litotipos diferentes de agregados. Os métodos CPT (método de prismas de concreto), ACPT (método acelerado de prismas de concreto) e ABCPT foram realizados com todos os agregados e após, uma análise comparativa foi realizada. Os resultados indicam que o ABCPT demonstra grande potencial para utilização na análise e classificação de agregados em obras correntes de engenharia. No entanto, para a sua real comprovação, torna-se muito importante a realização do ensaio com um maior número de amostras de diferentes litotipos.

There are many test methods used in the laboratory to detect potential alkali-aggregate reactions (AAR). However, up to now, there is no consensus if they are reliable and efficient. This work presents the development of a new and accelerated concrete prism test called ABCPT (accelerate Brazilian concrete prism test) as an attempt to create a reliable and fast test that can analyze and classify the potential reactivity of aggregates in the laboratory. For this research, six aggregates from different lithotypes were used. The methods CPT, ACPT and ABCPT were carried out with all the aggregates and a comparative analysis among all tests was performed. ABCPT seems to have a great potential to analyze and classify aggregates in the laboratory, although it needs further testing with other lithotypes to be confirmed as feasible.

Uma das principais limitações relacionadas ao processo de retificação de cerâmica é a confiabilidade do material devido aos defeitos introduzidos no processamento. A compreensão dos mecanismos envolvidos na remoção de material durante a retificação e a interação com os parâmetros de processo e microestrutura é fundamental para minimizar estes defeitos. A proposta desta revisão é apresentar os modelos de remoção de material e a forma como afetam as propriedades mecânicas da peça final.

One of the major restrictions in grinding of ceramics is the probability of failure of material due to the damage induced during the process. The understanding of mechanisms of material removal on grinding and the interaction with the process parameters and microstructure is fundamental to minimize these problems. The purpose of this review is to present the models of material removal in ceramics and the way they affect the mechanical properties of the product.