Relatório de estágio em farmácia comunitária

Relatório de estágio realizado no âmbito do Mestrado Integrado em Ciências Farmacêuticas, apresentado à Faculdade de Farmácia da Universidade de Coimbr

Influence of matric suction on shear strength behavior of a residual clayey soil

In this paper, the shear strength with respect to the matric suction of unsaturated soils was studied. For this purpose, unsaturated triaxial testing procedures were applied to the undisturbed residual soil specimens. An apparatus for performing triaxial tests was designed and constructed. In the tests, matric suction was controlled by using the axis translation technique, and pore water volume changes were measured by means of a volume change transducer with 10 -8 m 3 sensitivity. The test results indicated that the matric suction contributes to the shear strength of unsaturated soil specimens, and this contribution called suction strength varies non-linearly with respect to the matric suction. The logarithmic model needing to know the air-entry value and the internal friction angle of a soil specimen for prediction of the suction strength were presented and compared with the test results. It was found that suction strength values predicted from the proposed model were in satisfactory agreement with the experimental results. © 2007 Springer-Verlag

Influence of matric suction on shear strength behavior of a residual clayey soil

WOS: 000251142500017In this paper, the shear strength with respect to the matric suction of unsaturated soils was studied. For this purpose, unsaturated triaxial testing procedures were applied to the undisturbed residual soil specimens. An apparatus for performing triaxial tests was designed and constructed. In the tests, matric suction was controlled by using the axis translation technique, and pore water volume changes were measured by means of a volume change transducer with 10(-8) m(3) sensitivity. The test results indicated that the matric suction contributes to the shear strength of unsaturated soil specimens, and this contribution called suction strength varies non-linearly with respect to the matric suction. The logarithmic model needing to know the air-entry value and the internal friction angle of a soil specimen for prediction of the suction strength were presented and compared with the test results. It was found that suction strength values predicted from the proposed model were in satisfactory agreement with the experimental results

An approximation to the stress distribution analysis for anisotropic clayey soil

Although estimation of a stress distribution in a soil mass assumed as an anisotropic medium gives more realistic results but it is impractical since many elastic parameters are required to be measured. Possibility of more practical way of estimation of a stress distribution, including cross-anisotropy in a different and simpler manner is investigated in this research. In this study a new anisotropic parameter, s, was presented into the theoretical deduction. To see the performance of the proposed method, five independent cross-anisotropic elastic parameters such as EV, EH,?VH,?HH, GVH and anisotropic parameter, s, of a clayey soil were measured and stress distributions under the center of uniformly distributed circular area were portrayed for the same soil. In this frame, Finite Element Method (with crossanisotropic linear elastic material model), the proposed method, Boussinesq and Westergaard solutions were carried out and results were compared. It is found that the stresses obtained by the proposed way are compatible with the other solutions and also the stresses agreed with that of FEM analysis beneath a certain depth. © 2009 Academic Journals

Critical-state parameters of an unsaturated residual clayey soil from Turkey

This paper deals with the evaluation of the critical-state parameters with respect to the matric suction for saturated and unsaturated undisturbed residual clayey soils from Turkey. In order to conduct the unsaturated triaxial compression testing procedures a conventional triaxial compression apparatus was redesigned. The data for critical-state conditions from these tests are presented with respect to matric suction, based on the critical-state parameters of M, qo, ?, ?, which is commonly proposed by many authors. The critical state of the unsaturated samples is compared with that of the saturated samples. This experimental study has demonstrated that matric suction has no influence on parameters of M and ?. The parameters of M and ? are approximately 0.85 and 0.074 respectively for saturated and unsaturated conditions. The relationships between matric suction (ua - uw) and the intercepts qo and ? have been observed as nonlinear, and thus they can be defined as a function of matric suction (ua - uw). Furthermore, a method is developed to predict the intercepts q0 according to matric suction for unsaturated clayey soils. © 2007 Elsevier B.V. All rights reserved

Adaptive neuro-fuzzy modeling for the swelling potential of compacted soils

WOS: 000274180900013This paper aims to present the usability of an adaptive neuro fuzzy inference system (ANFIS) for the prediction swelling potential of the compacted soils that are important materials for geotechnical purposes such as engineered barriers for municipal solid waste, earth dams, embankment and roads. In this study the swelling potential that is also one of significant parameters for compacted soils was modeled by ANFIS. For the training and testing of ANFIS model, data sets were collected from the tests performed on compacted soils for different geotechnical application in Nigde. Four parameters such as coarse-grained fraction ratio (CG), fine-grained fraction ratio (FG), plasticity index (PI) and maximum dry density (MDD) were presented to ANFIS model as inputs. The results obtained from the ANFIS models were validated with the data sets which are not used for the training stage. The analyses revealed that the predictions from ANFIS model are in sufficient agreement with test results

Critical-state parameters of an unsaturated residual clayey soil from Turkey

WOS: 000250657400001This paper deals with the evaluation of the critical-state parameters with respect to the matric suction for saturated and unsaturated undisturbed residual clayey soils from Turkey. In order to conduct the unsaturated triaxial compression testing procedures a conventional triaxial compression apparatus was redesigned. The data for critical-state conditions from these tests are presented with respect to matric suction, based on the critical-state parameters of M, q(0), Gamma, lambda, which is commonly proposed by many authors. The critical state of the unsaturated samples is compared with that of the saturated samples. This experimental study has demonstrated that matric suction has no influence on parameters of M and lambda. The parameters of M and lambda are approximately 0.85 and 0.074 respectively for saturated and unsaturated conditions. The relationships between matric suction (u(a)-u(w)) and the intercepts q(0) and Gamma have been observed as nonlinear, and thus they can be defined as a function of matric suction (u(a)-u(w)). Furthermore, a method is developed to predict the intercepts q(0) according to matric suction for unsaturated clayey soils. (c) 2007 Elsevier B.V. All rights reserved