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Madrid, Spain

Jankovic V.,Typsa | Medina J.,ITC Inc
Australian Coasts and Ports 2015 Conference | Year: 2015

TYPSA, as a member of the COWI Consortium, completed the preliminary works under the EuropeAid Beneficiary Framework Contract funded by the European Union, to reestablish the cabotage system that once existed on the islands of Sao Tome and Principe (STP) in the Gulf of Guinea, off the western equatorial coast of Africa. Currently, there is no maritime component in the local transport system in STP. This is one of main causes of deterioration of the national road network, which currently bears the burden of all local transport on the main island. On the other hand, apart from limited passenger transport by air, transport to Principe Island is almost entirely by sea, but the size of the vessels is limited by the reduced depth of the only port on the island. After a detailed feasibility study and preliminary field works, six locations were selected from the more than twenty studied. Five of them were on Sao Tome and one on Principe. A greenfield port-development project will only be considered on Principe owing to the above-mentioned restrictive depths of the port, which would limit the size of the vessels in the system. In order to design these maritime works, field works were carried out at selected locations, maritime climate on both islands was assessed in detailed characterization studies and wave action was simulated in numerical models. At the time the work was done, only swell wave height time-series were available, but this analysis also introduces sea waves and presents detailed wave patterns in several areas on both islands. Once the numerical simulation of wave propagation had been finished, the results at the control point were analysed and the most unfavourable design conditions were defined, considering the simultaneous action of both sea states. Tides, surges and currents were also characterized and the projected climate change effects were taken into account. In the final phase of the contract, the detailed design for each port was completed, as well as the respective bidding documents for international tender for the works and purchase of necessary port equipment. Source

Albrecht Arquer G.,Typsa | Albrecht Arquer G.,Technical University of Madrid
Carreteras | Year: 2012

In the current situation, is particularly important to optimize road management. Actual boundary conditions that frame the development, maintenance and operation of these infrastructures drive to the management through indicators. Last recent experiences, both, at national and international level, show the main challenges of this new framework and the risks and advantages. Main aspects of the latest significant experiences in Spain are discussed, Therefore the importance of the selection, definition and specification of the indicators and the need for sensitivity studies with different scenarios on the degree of compliance with the indicator thresholds. It seems clear that this is the new model that will prevail in the future, though, to be successful it is necessary to involve all parties, leveraging our recent experiences. Source

The current system of procuring public works in Spain has room for improvement, particularly with respect to the hiring of professional services to perform the studies, design, control and monitoring of works. The forthcoming implementation of the so-called third-generation EU directives will provide a good opportunity for any such improvement. The article explains the fundamentals of the procurement of engineering services, with particular emphasis on the selection and awarding process. On the basis of his experience as president of TYPSA Group subsidiaries in the US, the author sets out his observations and appraisals, underlining a series of specific factors that should be known and taken into account in the current debate on the improvement of public procurement in Spain. The article describes two procedures: the traditional procedure of Design-Bid-Build, where the selection process of the consultants is based purely on the qualifications of the companies and their bids without initial consideration of the price factor; and the alternative procedure of Design-Build, more commonly used at present. Source

Sanchez-Jimenez J.L.,Typsa
NCEE 2014 - 10th U.S. National Conference on Earthquake Engineering: Frontiers of Earthquake Engineering | Year: 2014

The free - field racking deformation methodology has been agreed as the most reliable and rational approach for the design of tunnel infrastructures. Since its publication in the FHWA and AASHTO Tunnel Manual in 2010 is quickly becoming an international standard, as few other code references are available. The actual application of this method in shallow box - shaped tunnel infrastructure projects entails some considerations that contribute to its practical utilization. The main issue is related with the clear definition of the boundaries where the traditional dynamic earth pressure methods (i.e. Mononobe - Okabe and Wood) will still be applicable. Additionally the global effect of the structure racking distortion should be completed with the local effect that determines the earth pressure on the lateral walls. The key parameter appears to be the flexibility ratio, after which a simple procedure is proposed, in order to unify the results of the deformation method with the earth pressure approaches. On the other hand, the design of extremely flexible underground structures has to be accompanied with additional measures at least to avoid the joints decompression and consequences at the ground surface. Finally, the direct extrapolation of the successfully adopted criteria for the aboveground structures has to be observed carefully. Considering tunnel infrastructures, different issues would show up when relying on the plastic hinges formation, as the ulterior required reparation would present unaffordable problems in most cases. Source

Deu A.,Polytechnic University of Catalonia | Romero E.,Polytechnic University of Catalonia | Plaza A.,Typsa | Berdugo I.R.,Universidad del Norte, Colombia
Unsaturated Soils: Research and Applications - Proceedings of the 6th International Conference on Unsaturated Soils, UNSAT 2014 | Year: 2014

Precipitation of sulphate crystals in discontinuities due to evaporation of sulphate solutions is an important contribution to the degradation and swelling behavior of sulphate bearing argillaceous rocks. Although the phenomenon has been studied in laboratory during decades linked to the expansive behavior in tunnels, tests do not adequately reproduce field conditions and all variables involved in the swelling mechanism. Size effect problems and the difficulty in correctly applying hydraulic boundary conditions are the main aspects behind these experimental difficulties. To this aim, a new experimental setup has been designed to allow applying relative humidity control on the top cap of the sample, while the bottom cap is in permanent contact with a saturated sulphate solution. This way, controlled solvent evaporation conditions are applied, which control the rate of sulphate precipitation on the sample. The crystals are deposited along preferential discontinuities of the sample, as well as on fissures generated by the hydraulically induced degradation of the material. A sulphate bearing claystone of the Lower Ebro Basin (Catalonia, Spain) has been tested. Selected swelling tests are presented at different relative humidity values. Microstructural and DRX analyses are also included to complement the information of the mineralogical phases deposited during these processes. © 2014 Taylor & Francis Group, London. Source

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