Selling consultancy services: the Portuguese case in historical and comparative perspective

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Vulnerability assessment of the S. João de Loure Bridge: Vouga’s river

Steel bridges are particularly sensible to corrosion, which can put at risk the structural safety by affecting the joint elements. Having this in mind, the objective of this work was to evaluate the influence of the joint's stiffness in the structural response of the S. João de Loure steel bridge. An improved model was developed for the bridge on the structural analysis software SAP2000. Maximum deflection, axial forces and corresponding stresses, and natural frequencies, were analyzed. Numerical results allow concluding about the influence of the joint's stiffness in the structural response of the bridge

S. João de Loure Bridge: vulnerability assessment and study of a common strengthening solution

This paper presents a structural vulnerability assessment of the steel bridge S. João de Loure. A structural model of the bridge was created and the influence of the joint’s stiffness on its structural response was evaluated using the structural analysis software SAP2000. Natural frequencies, axial forces and corresponding stress, and maximum mid-span deflection, were analyzed. A common strengthening solution with prestressing cables was studied intending to reduce the bridge’s mid-span deflection

Mechanical characterization of adobe bricks in existing constructions in Aveiro Region, Portugal

In Portugal it is common to find earth constructions all over the country, being predominant in the centre and south. In the past, earth was massified as a construction material, used with different typologies and applications. Adobe construction is confined mainly to the central part of the country and more viewed in the west coast (gandaresa region). Aveiro, an Atlantic sea line city is an excellent example of a place with several ancient adobe constructions, some with architectural and historical relevance like some art-noveau houses. Just a few ones have been preserved with the passing years. The majority are in the threshold of ruin and structurally weak needing an urgent solution for their furtherance as buildings. Preservation and rehabilitation of those constructions was simply forgotten, carrying to the actual situation. In this context, becomes urgent, and absolutely necessary, to advance with rehabilitation and strengthening of these constructions. A great difficulty for technicians working on the rehabilitation relies on the lack of knowledge on adobe’s mechanical behaviour. In fact, in order to properly describe the structural behaviour of those constructions, there’s a need to investigate the mechanical properties of adobe. Hence, this paper presents a study which intended to characterise the behaviour of adobe brick units. Specimens were prepared from selected representative Aveiro’s constructions. The prepared specimens were tested in order to evaluate their mechanical behaviour in compression and tension. Usually, adobe blocks were made from clay soils. A basic characterization was also performed by the adobes’ granulometric analysis

Vibration control of single floor seismically excited structure using active mass damper

The purpose of this paper is to dampen the vibrations using active mass damper (AMD) flexible structure has been tested using Shake Table by linear cart. The active and passive mass properties has been discussed. An observer based state-feedback card controller was used for one floor AMD using MATLAB/SIMULINK modelling. Several laboratory experimental setup using AMD, general system description, model, parameters, and comparison of data obtained by Pakistan earthquake occurred on Oct 8, 2005 has been discussed

Structural optimisation problem in support to building retrofitting decision

Various analysis methods, either linear elastic or non-linear, static or dynamic, are available for the performance analysis of existing buildings. Despite its advantages, it must be admitted that non-linear time history analysis can frequently become overly complex and impractical for general use as a first assessment. Simplified models, as the Capacity Spectrum Method, are frequently not able to accurately assess irregular structures. Considering these limitations, it is proposed and evaluated a simplified MDOF non-linear dynamic model, accounting for non-linear storey behaviour and storey damping. Based on the MDOF non-linear dynamic model, were developed optimization algorithms for the redesign of existing non-seismically designed structures. The optimization procedure searches for the optimum storey strengthening distribution (strength, stiffness or damping) in order to meet specific performance requirements, in terms of maximum inter-storey drift for a given seismic demand level. Numerical examples are presented in order to illustrate the capability of methodology

A geometrical non-linear model for cable systems analysis

Cable structures are commonly studied with simplified analytical equations. The evaluation of the accuracy of these equations, in terms of equilibrium geometry configuration and stress distribution was performed for standard cables examples. A three-dimensional finite element analysis (hereafter FEA) procedure based on geometry-dependent stiffness coefficients was developed. The FEA follows a classical procedure in finite element programs, which uses an iterative algorithm, in terms of displacements. The theory is based on a total Lagrange formulation using Green-Lagrange strain. Pure Newton-Raphson procedure was employed to solve the non-linear equations. The results show that the rigid character of the catenary’s analytical equation, introduce errors when compared with the FEA

Numerical model to account for the influence of infill masonry on the RC structures behaviour

It is a common misconception considers that masonry infill walls in structural RC buildings can only increase the overall lateral load capacity, and, therefore, must always be considered beneficial to seismic performance. Recent earthquakes have showed numerous examples of severe damages or collapses of buildings caused by structural response modification induced by the non-structural masonry partitions. From a state-of-the-art review of the available numerical models for the representation of the infill masonry behaviour in structural response, it was proposed an upgraded model. The proposed model is inspired on the equivalent bi-diagonal compression strut model, and considers the non-linear behaviour of the infill masonry subjected to cyclic loads. The model was implemented and calibrated in a non-linear dynamic computer code, VISUALANL. In this paper, it is presented the proposed model and the results of the calibration analyses are briefly introduced and discussed

On R&D, medium and high-tech industries and productivity: an application to the Portuguese case

This paper investigates the potential impact of increased R&D efforts and structural changes in Portugal on labour productivity. The paper addresses Portugal’s ambition, expressed in the 2005 Technological Plan. Based on existing literature on the relation between R&D expenditures, structural change and productivity, we evaluate the contribution of R&D and medium to high-tech industries on productivity over the last 30 years. Our results confirm the importance of governement’s R&D and of business R&D in the medium to high-tech sectors, as they stimulate productivity growth. However, we cannot hypothesize that productivity growth was primarily rooted on the development of medium-high technology industries.Manufacturing, Productivity, Structural Change, R&D, High-tech industries

MODES OF INNOVATION & UNCERTAINTIES IN THE CAPITAL GOODS INDUSTRY

Product innovation is a subtle process, frequently leading to shifts in the competitiveness of firms. Developing products in an environment undergoing technological change is given to frequent failure, even in well-established and sophisticated organizations. In order to tackle competitiveness and to deal with innovation uncertainty, firms develop diverse innovation processes. Two modes of innovation are suggested in recent literature: 1) Science, Technology and Innovation (STI) mode, which is based on the production and use of codified scientific and technical knowledge; and 2) Doing, Using and Interacting (DUI) mode, which relies on informal processes of learning and experience-based know-how. In this paper we analyse product innovation at firm level. We perform an exploratory analysis in four leading equipment and machinery producers from the Aveiro region, in Portugal. Doing so, we explore the main features of the capital goods’ industry with implications for innovation, and analyse the dominant uncertainties associated to the innovation process. and modes of innovation. Key findings include the complete absence of DUI mode in the cases studied, and even a low learning characteristic in one company. The paper concludes by considering the implications for firms’ competitiveness and for innovation policy.modes of innovation, uncertainties, R&D, capital goods, SME