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The paper reports experimental and numerical simulation of ballistic impact problems on thin composite laminated plates reinforced with Kevlar 29. Ballistic impact was imparted with simulated fragments designed in accordance with STANAG-2920 on plates of different thickness. Numerical modelling was developed and used to obtain an estimate for the limit perforation velocity V50 and simulate failure modes and damage. Computations were carried out using a commercial code based on nite differences and values obtained are compared with the experimental data to evaluate the performance of the simulation. Good correlation between computational simulation and experimental results was achieved, both in terms of deformation and damage of the laminates. Future work is advanced to include the interposition of an outer ceramic layer as well as examining the influence of dry-wet and temperature cycles on the mechanical strength of the plates and their temporal evolution under accelerated ageing.

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This thesis deals with the analysis of the behaviour of retrofitting reinforced concrete circular columns with FRP materials which were subjected either to axial cyclic compression or axial compression and alternated cyclic horizontal loads. The choice of this topic derived from the need to investigate the behaviour of the strengthening of reinforced concrete columns to seismic actions, especially with new materials such as carbon and glass fibres or polymeric mortars. Another reason for such choice is linked to the strong seismicity of the Portuguese territory.
It has been verified that confined concrete columns with FRP jackets have their resistance and ductility highly increased as these considerably reduce the columns transversal deformation, thus preventing the buckling of longitudinal reinforcement. There has been an increasing use of FRP composites in the strengthening of structures, mainly with GFRP (Glass Fibre Reinforced Plastics) or CFRP (Carbon Fibre Reinforced Plastics). This is due to their attractive characteristics such as high resistance to corrosion, lowratio for weight/strength, moldability, easy application and the fact that there is no need of support structures.
Forty-five experimental tests were carried out, dealing with retrofitting reinforced concrete columns with axial monotonic or cyclic compression reinforced with FRP composites. The column height of 750 mm was maintained in order to evaluate the influence of several parameters in its behaviour: the column geometry (change in its diameter), the type of column (plain or reinforced concrete), transversal reinforcement ratio of concrete columns, the type of external confinement with FRP (C or GFRP), the number of FRP layers and the type of axial loading (monotonic or cyclic).
Twelve additional experimental tests were conducted in order to analyse the behaviour of reinforced concrete columns jacketed with FRP composites and subjected to axial cyclic compression and alternated cyclic horizontal loads. The columns’ dimension was maintained (1500 mm height by 250 mm diameter) and the models were subjected to a series of cyclic and alternated loadings. This enabled the study of the various parameters’ influence in their behaviour such as the type of FRP confinement, the number of FRP layers, the level of axial loading, the jacket’s height or the strengthening of the plastic hinge by replacing the cover concrete with polymeric mortar.
Based on the numerical models presented and experimental analysis carried out, models were proposed and developed to simulate the behaviour of columns jacketed with FRP composites.

{Summary: We are interested in an adequate estimation of the dominant component of the bias of ıt B. M. Hill}\,'s estimator [Ann. Stat. 3, 1163–1174 (1975; Zbl 0323.62033)] of a positive tail index $\gamma$, in order to remove it from the classical Hill estimator in different asymptotically equivalent ways. If the second order parameters in the bias are computed at an adequate level $k_1$ of a larger order than that of the level $k$ at which the Hill estimator is computed, there may be no change in the asymptotic variances of these reduced bias tail index estimators, which are kept equal to the asymptotic variance of the Hill estimator, i.e., equal to $\gamma^2$. The asymptotic distributional properties of the proposed estimators of $\gamma$ are derived and the estimators are compared not only asymptotically, but also for finite samples through Monte Carlo techniques.}

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This paper is mainly focused on the characterisation of a glass material (GM) obtained from the thermal treatment of a bottom ash (BA) produced at the Municipal Solid Waste (MSW) incineration plant of Valorsul. By melting the BA at 1400ºC during 2 hours, and without using any chemical additives, a homogeneous black-coloured glass was obtained. The thermal and mechanical properties of this glass were characterised. The thermal expansion coefficient, measured by dilatometry, was 9-10 x 10-6 per ºC and the modulus of rupture, determined by four-point bending test, was 75±6 MPa, which are similar values to those exhibited by commercial soda-lime-silica glasses used in structural applications. The chemical and the ecotoxicological leaching behaviour of the GM were also analysed. The GM was submitted to a leaching procedure composed of 15 sequential extraction cycles. A liquid/solid (L/S) ratio of 2 l/kg was applied in each cycle. The leachates were filtered through a membrane of PTFE (porosity: 0.45 µm). The filtered leachates were characterised for different chemical parameters and for an ecotoxicological indicator (bacterium Vibrio fischeri). The GM was also submitted to a microwave acidic digestion for the assessment of the total metal content. The crude BA was also submitted to the same experimental procedures. The GM showed levels of chemical emission and ecotoxicity for V. fischeri much lower than those determined for the crude BA. Similar characterisation studies will be pursued with the glass-ceramics produced by adequate thermal treatment of the glass, in order to investigate the effect of the crystallization on the final properties.

Logistics performance can be affected by the presence of uncertainties in the decision making process. To reduce decision making uncertainties, a topology of sources of supply chain ({SC)} uncertainty is proposed, in order to identify different types of uncertainty. A conceptual framework is developed for the analysis of decision making uncertainty sources in {SC’s}, providing the basis for the design and selection of improved {SC} scenarios. A case study is presented to illustrate the potential of simulation techniques in modeling scenarios for the Supply Chain: a set of performance measures is proposed, and results are obtained based on a predetermined selection criterion.

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