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The engineering properties of Portuguese processed steel slags (ISACs) are tested to evaluate the... more The engineering properties of Portuguese processed steel slags (ISACs) are tested to evaluate the appropriateness of their use in transportation infrastructures and geotechnical works. The laboratory results are compared with values specified in the Portuguese ...

Abstract In an organizational sphere of great dynamism and mutability, the effectiveness of group... more Abstract In an organizational sphere of great dynamism and mutability, the effectiveness of group work in companies and institutions is assumed as one of the most important success factors to achieve their objectives. The computer has acquired a strategic task in the support of cooperative work processes, raising a fruitful symbiosis between humans and machines with different functions but strongly interconnected. This article examines the holistic nature of Computer Supported Cooperative Work, an interdisciplinary scientific field that has ...

The results of an experimental work on two road granular materials are presented, including small... more The results of an experimental work on two road granular materials are presented, including small strains precision triaxial tests under cyclic loading, large strains triaxial tests with measurement of the negative pore water pressure (suction) and wetting tests. The influence of different initial conditions of density, water content and fines content was studied. The two ma- terials differ by their fine contents (7 % for MHC and 10% for HFC). The specimens are com- pacted at different water content and at a density corresponding to 97% of the Modified Proctor maximum density. The interpretation of the results, in the quasi-elastic domain, is based on an effective stress analysis that allows to take into account both the effects of total stresses and nega- tive pressure, in the perspective of a more rational design of pavement layers.

A geothermal anomaly with heat flow density (HFD) values of about 200 near its center has been re... more A geothermal anomaly with heat flow density (HFD) values of about 200 near its center has been reported to exist in southern Portugal. The area where the anomaly is claimed to occur is geologically complex and is crossed by two major tectonic features: the Messejana fault and the Ferreira-Ficalho overthrust. A magnetotelluric (MT) survey was carried out in the region of the highest reported HFD values with the intent of delineating the anomaly in electrical terms and understanding its origin. Thirty-four MT sites were occupied over an area of about 2,500 and, after processing the MT data, electrical resistivity maps at several depths were constructed. Interpretation of the processed data indicates that the HFD values reported for the area of the MT survey do not represent the thermal state of the upper crust in the region. However, low electrical resistivity values are found in zones that coincide at the surface with the Messejana fault and the Ferreira-Ficalho overthrust. This may ...

The study of the climate in the past and the climate change in mainland Portugal using geothermal... more The study of the climate in the past and the climate change in mainland Portugal using geothermal data has started in 1996. Reconstruction of ground surface temperature (GST) history from temperature logs measured in a 200 m deep borehole located 5 km away from the town of Évora in Portugal, indicates a warming of 1K since the second half of the nineteenth century to the middle of the 90s of the twentieth century, increasing considerably in the last 10 years. Results of the reconstruction (based on a functional space inversion – FSI – method) are compared with air temperatures recorded at the Lisbon meteorological station since 1856. The airtemperature time series display a warming trend with the amplitude about 1K for the same period. The coupling of the air and ground temperature changes and their downward propagation by heat conduction was confirmed by repeated logging in November 2003, 6.7 years after obtaining the first temperature log. The method can be used in paleoclimatic s...

Basic features and problems of the method of reconstruction of the ground surface temperature his... more Basic features and problems of the method of reconstruction of the ground surface temperature history from the temperature-depth profiles measured at present in boreholes are outlined and illustrated. The main methodological problem is the one-dimensional, purely conductive representation of the subsurface temperature field used by all existing systematic inversion algorithms. It prevents considering lateral inhomogeneities of thermophysical parameters of rocks, effects of topography and space variations of the surface temperature as well as any departures from the conductive mode of the subsurface heat transfer. It can be overcome by "non-systematic" approaches like Monte-Carlo method, which requires solution of the direct problem only. The main practical problem is the presence of noise in the temperature logs which contributes, together with the diffusive character of the downward propagation of the surface changes, to the rapid lost of resolution of the more remote sur...

RESUMO A presente comunicação apresenta várias técnicas de instrumentação local para medição das ... more RESUMO A presente comunicação apresenta várias técnicas de instrumentação local para medição das deformações verticais e radiais de provetes triaxiais cilíndricos e prismáticos, relatando vantagens e inconvenientes das mesmas. Incluem-se nestas técnicas: LVDT (Linear Variable Differential Transformer), LDT (Local Deformation Transducers), efeito de Hall e transdutores piezoeléctricos. Apresentam-se resultados experimentais obtidos sobre um mesmo solo com recurso a estes diferentes tipos de instrumentação na perspectiva de comparar os resultados obtidos, e mostrar a sua influência, muito particularmente, nas curvas de degradação do módulo com o nível de deformação, varrendo o domínio das pequenas às médias deformações. Além disso, ilustram-se também resultados obtidos em diferentes tipos de materiais recorrendo ao uso de LDT's implementados no Laboratório de Engenharia Civil da Universidade do Minho. ABSTRACT This paper presents several techniques of local instrumentation to meas...

Cited By (since 1996):1, Export Date: 1 October 2013, Source: Scopus

This paper presents the results of several resonant column tests carried out in a large variety o... more This paper presents the results of several resonant column tests carried out in a large variety of soils, including lateritic and saprolitic tropical soils. The data analysed are restricted to the strain dependence of shear modulus in the range of 10-6 to 10-2. Despite the different isotropic consolidated stresses, degrees of saturation and overconsolidation ratios applied for the different types of soil, all the test results fit very well in a previous proposed normalised curve of G/Go as a function of y/yO.,, where yo.7 is the shear strain corresponding to a value of G=0.7 x Go. The hyperbolic stress-strain equation can conveniently describe this fitting. Simple practical relationships are also proposed for tropical soils to the prediction of Go and yo7 allowing with the normahsed curve to estimate shear modulus in the strain range relevant to the service state of many civil engineering structures.

A resposta sísmica de cortinas bi-ancoradas suportando areia é avaliada com recurso a ensaios din... more A resposta sísmica de cortinas bi-ancoradas suportando areia é avaliada com recurso a ensaios dinâmicos 1g em mesa sísmica. São apresentados e discutidos os aspetos relacionados com a execução do modelo físico, nomeadamente o faseamento construtivo e os equipamentos de observação utilizados. São apresentadas as condições de realização dos ensaios e discutidos os resultados obtidos. Palavras-chave: dinâmica de solos; modelo físico 1g; cortinas ancoradas; contentor flexível.

Conference code: 92003, Cited By (since 1996):1, Export Date: 29 September 2013, Source: Scopus, ... more Conference code: 92003, Cited By (since 1996):1, Export Date: 29 September 2013, Source: Scopus, doi: 10.3233/978-1-60750-031-5-777, Language of Original Document: English, Correspondence Address: Bicalho, K.V.; Federal University of Espirito Santo, Vitoria, ES, Brazil, References: Al-Khafaf, S., Hanks, R.J., Evaluation of the filter paper method for estimating soil water potential (1974) Soil Sci., 117, pp. 194-199;

Cited By (since 1996):2, Export Date: 1 October 2013, Source: Scopus

A tecnologia de Jet Grouting (JG), caracterizada pela sua grande versatilidade, é actualmente uma... more A tecnologia de Jet Grouting (JG), caracterizada pela sua grande versatilidade, é actualmente uma das principais soluções de tratamento de solos. Contudo, apesar de todo o seu potencial carece de regras de dimensionamento e controlo de qualidade, verificando-se inclusive que as principais obras de JG são planeadas com base em algumas regras empíricas, que estimam muito conservativamente as propriedades físicas e mecânicas do material tratado. O desenvolvimento de modelos racionais capazes de simular o efeito dos diferentes parâmetros que intervêm no processo de JG é uma necessidade primordial, de forma a satisfazer o binómio segurança-economia subjacente a qualquer projecto de engenharia. Por outro lado, actualmente estão emergindo poderosas ferramentas que permitem colectar, armazenar e processar grandes, volumes de dados, tais como as técnicas de Data Mining. No presente estudo, foram aplicadas esta técnicas na definição de modelos previsionais da resistência à compressão uniaxial...

Geophysical surveying has been proven to be an effective method to unveil the distribution of per... more Geophysical surveying has been proven to be an effective method to unveil the distribution of permafrost conditions in polar environments. In the South Shetland Islands permafrost is considered to be marginal to discontinuous until elevations of 20-40 m asl changing to continuous at higher altitudes. However, there is no specific data about the distribution of permafrost in the recently deglaciated areas in the Byers Peninsula (Livingston Island, Antarctica), the largest ice-free area in the South Shetland Islands. With the purpose of better understanding the existence or inexistence of permanent frozen conditions in this area, we have conducted a field season focusing on the geophysical surveying along two transects: from the coast to the highest marine terraces and from the glacier to the central plateau. The snowy conditions during the cold season in 2014 in the Byers Peninsula have conditioned a late melting of snow, which must be taken into account when interpreting the data re...

Cited By (since 1996):1, Export Date: 1 October 2013, Source: Scopus

The engineering properties of Portuguese processed steel slags (ISACs) are tested to evaluate the... more The engineering properties of Portuguese processed steel slags (ISACs) are tested to evaluate the appropriateness of their use in transportation infrastructures and geotechnical works. The laboratory results are compared with values specified in the Portuguese ...

Abstract In an organizational sphere of great dynamism and mutability, the effectiveness of group... more Abstract In an organizational sphere of great dynamism and mutability, the effectiveness of group work in companies and institutions is assumed as one of the most important success factors to achieve their objectives. The computer has acquired a strategic task in the support of cooperative work processes, raising a fruitful symbiosis between humans and machines with different functions but strongly interconnected. This article examines the holistic nature of Computer Supported Cooperative Work, an interdisciplinary scientific field that has ...

The results of an experimental work on two road granular materials are presented, including small... more The results of an experimental work on two road granular materials are presented, including small strains precision triaxial tests under cyclic loading, large strains triaxial tests with measurement of the negative pore water pressure (suction) and wetting tests. The influence of different initial conditions of density, water content and fines content was studied. The two ma- terials differ by their fine contents (7 % for MHC and 10% for HFC). The specimens are com- pacted at different water content and at a density corresponding to 97% of the Modified Proctor maximum density. The interpretation of the results, in the quasi-elastic domain, is based on an effective stress analysis that allows to take into account both the effects of total stresses and nega- tive pressure, in the perspective of a more rational design of pavement layers.

A geothermal anomaly with heat flow density (HFD) values of about 200 near its center has been re... more A geothermal anomaly with heat flow density (HFD) values of about 200 near its center has been reported to exist in southern Portugal. The area where the anomaly is claimed to occur is geologically complex and is crossed by two major tectonic features: the Messejana fault and the Ferreira-Ficalho overthrust. A magnetotelluric (MT) survey was carried out in the region of the highest reported HFD values with the intent of delineating the anomaly in electrical terms and understanding its origin. Thirty-four MT sites were occupied over an area of about 2,500 and, after processing the MT data, electrical resistivity maps at several depths were constructed. Interpretation of the processed data indicates that the HFD values reported for the area of the MT survey do not represent the thermal state of the upper crust in the region. However, low electrical resistivity values are found in zones that coincide at the surface with the Messejana fault and the Ferreira-Ficalho overthrust. This may ...

The study of the climate in the past and the climate change in mainland Portugal using geothermal... more The study of the climate in the past and the climate change in mainland Portugal using geothermal data has started in 1996. Reconstruction of ground surface temperature (GST) history from temperature logs measured in a 200 m deep borehole located 5 km away from the town of Évora in Portugal, indicates a warming of 1K since the second half of the nineteenth century to the middle of the 90s of the twentieth century, increasing considerably in the last 10 years. Results of the reconstruction (based on a functional space inversion – FSI – method) are compared with air temperatures recorded at the Lisbon meteorological station since 1856. The airtemperature time series display a warming trend with the amplitude about 1K for the same period. The coupling of the air and ground temperature changes and their downward propagation by heat conduction was confirmed by repeated logging in November 2003, 6.7 years after obtaining the first temperature log. The method can be used in paleoclimatic s...

Basic features and problems of the method of reconstruction of the ground surface temperature his... more Basic features and problems of the method of reconstruction of the ground surface temperature history from the temperature-depth profiles measured at present in boreholes are outlined and illustrated. The main methodological problem is the one-dimensional, purely conductive representation of the subsurface temperature field used by all existing systematic inversion algorithms. It prevents considering lateral inhomogeneities of thermophysical parameters of rocks, effects of topography and space variations of the surface temperature as well as any departures from the conductive mode of the subsurface heat transfer. It can be overcome by "non-systematic" approaches like Monte-Carlo method, which requires solution of the direct problem only. The main practical problem is the presence of noise in the temperature logs which contributes, together with the diffusive character of the downward propagation of the surface changes, to the rapid lost of resolution of the more remote sur...

RESUMO A presente comunicação apresenta várias técnicas de instrumentação local para medição das ... more RESUMO A presente comunicação apresenta várias técnicas de instrumentação local para medição das deformações verticais e radiais de provetes triaxiais cilíndricos e prismáticos, relatando vantagens e inconvenientes das mesmas. Incluem-se nestas técnicas: LVDT (Linear Variable Differential Transformer), LDT (Local Deformation Transducers), efeito de Hall e transdutores piezoeléctricos. Apresentam-se resultados experimentais obtidos sobre um mesmo solo com recurso a estes diferentes tipos de instrumentação na perspectiva de comparar os resultados obtidos, e mostrar a sua influência, muito particularmente, nas curvas de degradação do módulo com o nível de deformação, varrendo o domínio das pequenas às médias deformações. Além disso, ilustram-se também resultados obtidos em diferentes tipos de materiais recorrendo ao uso de LDT's implementados no Laboratório de Engenharia Civil da Universidade do Minho. ABSTRACT This paper presents several techniques of local instrumentation to meas...

Cited By (since 1996):1, Export Date: 1 October 2013, Source: Scopus

This paper presents the results of several resonant column tests carried out in a large variety o... more This paper presents the results of several resonant column tests carried out in a large variety of soils, including lateritic and saprolitic tropical soils. The data analysed are restricted to the strain dependence of shear modulus in the range of 10-6 to 10-2. Despite the different isotropic consolidated stresses, degrees of saturation and overconsolidation ratios applied for the different types of soil, all the test results fit very well in a previous proposed normalised curve of G/Go as a function of y/yO.,, where yo.7 is the shear strain corresponding to a value of G=0.7 x Go. The hyperbolic stress-strain equation can conveniently describe this fitting. Simple practical relationships are also proposed for tropical soils to the prediction of Go and yo7 allowing with the normahsed curve to estimate shear modulus in the strain range relevant to the service state of many civil engineering structures.

A resposta sísmica de cortinas bi-ancoradas suportando areia é avaliada com recurso a ensaios din... more A resposta sísmica de cortinas bi-ancoradas suportando areia é avaliada com recurso a ensaios dinâmicos 1g em mesa sísmica. São apresentados e discutidos os aspetos relacionados com a execução do modelo físico, nomeadamente o faseamento construtivo e os equipamentos de observação utilizados. São apresentadas as condições de realização dos ensaios e discutidos os resultados obtidos. Palavras-chave: dinâmica de solos; modelo físico 1g; cortinas ancoradas; contentor flexível.

Conference code: 92003, Cited By (since 1996):1, Export Date: 29 September 2013, Source: Scopus, ... more Conference code: 92003, Cited By (since 1996):1, Export Date: 29 September 2013, Source: Scopus, doi: 10.3233/978-1-60750-031-5-777, Language of Original Document: English, Correspondence Address: Bicalho, K.V.; Federal University of Espirito Santo, Vitoria, ES, Brazil, References: Al-Khafaf, S., Hanks, R.J., Evaluation of the filter paper method for estimating soil water potential (1974) Soil Sci., 117, pp. 194-199;

Cited By (since 1996):2, Export Date: 1 October 2013, Source: Scopus

A tecnologia de Jet Grouting (JG), caracterizada pela sua grande versatilidade, é actualmente uma... more A tecnologia de Jet Grouting (JG), caracterizada pela sua grande versatilidade, é actualmente uma das principais soluções de tratamento de solos. Contudo, apesar de todo o seu potencial carece de regras de dimensionamento e controlo de qualidade, verificando-se inclusive que as principais obras de JG são planeadas com base em algumas regras empíricas, que estimam muito conservativamente as propriedades físicas e mecânicas do material tratado. O desenvolvimento de modelos racionais capazes de simular o efeito dos diferentes parâmetros que intervêm no processo de JG é uma necessidade primordial, de forma a satisfazer o binómio segurança-economia subjacente a qualquer projecto de engenharia. Por outro lado, actualmente estão emergindo poderosas ferramentas que permitem colectar, armazenar e processar grandes, volumes de dados, tais como as técnicas de Data Mining. No presente estudo, foram aplicadas esta técnicas na definição de modelos previsionais da resistência à compressão uniaxial...

Geophysical surveying has been proven to be an effective method to unveil the distribution of per... more Geophysical surveying has been proven to be an effective method to unveil the distribution of permafrost conditions in polar environments. In the South Shetland Islands permafrost is considered to be marginal to discontinuous until elevations of 20-40 m asl changing to continuous at higher altitudes. However, there is no specific data about the distribution of permafrost in the recently deglaciated areas in the Byers Peninsula (Livingston Island, Antarctica), the largest ice-free area in the South Shetland Islands. With the purpose of better understanding the existence or inexistence of permanent frozen conditions in this area, we have conducted a field season focusing on the geophysical surveying along two transects: from the coast to the highest marine terraces and from the glacier to the central plateau. The snowy conditions during the cold season in 2014 in the Byers Peninsula have conditioned a late melting of snow, which must be taken into account when interpreting the data re...

Cited By (since 1996):1, Export Date: 1 October 2013, Source: Scopus