Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 7

Liczba wyników na stronie
first rewind previous Strona / 1 next fast forward last
Wyniki wyszukiwania
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 1 next fast forward last
EN
Considering the demand for mooring larger ships at Brazilian port terminals, both private and public, in a scenario of growing exports, engineering interventions that can provide improvements in the vessel’s maximum allowed dimensions can represent significant profits. Hence, this work presents an approach of Nautical Bottom, defined as the minimum depth in which ships can navigate without significant adverse effects in ship control and maneuverability without physical damage, with the goal of raising the maximum ship draft allowed in nautical spaces with fluid mud beds. Due to its rheological properties, fluid mud, in general, allows for vessels navigate with low or negative under keel clearance, respecting the established Nautical Bottom concepts. In addition, fluid mud layer thickness at port areas can possibly vary according to hydrodynamics and sedimentologic variations. This article presents an analysis of fluid mud thickness variations within the Itajaí Port Complex (Santa Catarina, Brazil) turning basin, where fluid mud layers are up to 2.5 meters thick, by means of analyses of bathymetric surveys and numerical modeling. The Itajaí Port Complex is located at the Itajaí-açu river estuary, which presents high variability of river discharge and suspended sediments. From bathymetric surveys, it is possible to observe fluid mud thickness from 0.5 to 2.5 meters. Numerical simulation results indicate suspended sediment load as a main environmental aspect for fluid mud thickness variations in the study area.
2
Content available Estimation of Sea Level Rise in Santos Port (Brazil)
EN
Santos Port is located in São Paulo State Coast (Brazil), in an estuarine area inside Santos Bay named Baixada Santista. The currents behavior is forced by tides. The resulting tidal level variability (high tide, mean sea level and low tide) recorded from Santos Dock Company tide gauge (1940 to 2014), the longest series of continuous record of tides in Brazil, shows a consistent increasing trend. The estimation about the magnitude of mean sea level rise (MSLR) in recommendations, guidelines or requirements issued by different countries and agencies from 1990 provide examples of different approaches used around the world in comparison with the local trends obtained for Santos Port. It is concluded that MSLR will have a considerable impact upon the port, with approximately 1.0 m rise estimated from 1990 to 2100. Baixada Santista is a lowland situated a few meters upper from the sea level and some areas are possible to be submerged in the end of this century. Other two locations in São Paulo State Coast, Cananeia and Ubatuba, respectively to the SE and NW of Santos, were also compared with the port tidal data to evaluate the consistency of the trends.
EN
Santos Port is located in Brazilian coast, in an estuarine area inside Santos Bay named Baixada Santista. The currents behavior is forced by tides. The resulting tidal level variability (high tide, mean sea level and low tide) recorded from Santos Dock Company tide gauge (1940 to 2014) shows a consistent increasing trend. The estimation about the magnitude of mean sea level rise (MSLR) in recommendations, guidelines or requirements issued by different countries and agencies from 1990 provide examples of different approaches used around the world in comparison with the local trends obtained for Santos Port. It is concluded that MSLR will have a considerable impact upon the port and adjacent areas, with approximately 1.0 m rise estimated from 1990 to 2100. Baixada Santista is a lowland situated a few meters upper from the sea level and some areas are possible to be submerged in the end of this century. Not only the wetlands of mangroves will be affected, but also the infrastructures, residential zones and the port will face problems. The major SLR impacts upon port operation will be the reduction of freeboard of the quays, flooding of storage yards (and other low storage areas) and of the internal transport tracks or rails. Also the increasing sedimentation in the nautical areas of access channels, turning basins and berths, will induce more maintenance dredging.
EN
For the enlargement of the nautical dimensions of Santos Port Outer Access Channel (Brazil), training walls crossing the Offshore Bar are needed. The training walls choice to reduce dredging rates also induces to consider a coupling planning between nautical purposes and shore protection measures, as Santos Municipality have serious erosion problems nowadays due to the urban growth in the backshore and sea level rise. For decision support, the Hydraulic Laboratory of Engineering School of University of Sao Paulo was commissioned to study in a composite mathematical and scale model. Results include changes in wave height and direction and current speed analysis to conditions with training walls and segmented breakwaters. The water renewal was also analyzed to the condition with segmented breakwater and compared to current situation, based on hydrodynamics results and considering that this structure can reduce water quality in this area.
EN
Santos Harbor Area (SHA) in Sao Paulo Coastline (Brazil) is the most important marine cargo transfer terminal in the Southern Hemisphere. A long term relative tidal level variability assessment shows a consistent response to relative sea level rise. A wave data base Wave Watch III was compared with a long term wave data-base generated by the ERA40-ECMWF (2003), both local validated. The current bed level of SHA Outer Channel is -15.00 m (Chart Datum or, in abbreviation, CD), maintained by dredging. According to the cargo throughput forecast, in 2025, the Access Channel will have to be deepened to level of -17.00 m. The feasibility of that choice is discussed from a technical, economical and conceptual navigation point of view in that context. A data set found from a scale model of the whole area of Santos Bay, Estuary and nearby beaches, showed the impact of maritime climate changes upon the coastal area. In the previous researches developed by the authors, it was demonstrated that the wave climate, the tides and tidal currents affect harbor and coastal structures maintenance, beaches stability, tidal inlet, sediment transport, saline intrusion and wetlands. Considering the increasing of the sea hazards and the high values of the infrastructures in that coastline, it is necessary to mitigate the risks. Hence, based on the results obtained by the authors, are highlighted guidelines strategies suggested for Access Channels dimensions, wharves free-board, jetties dimensions, dredging rates, rigid and flexible littoral defenses and land protection against flooding (including wetlands).
EN
According to the IPCC, the forecast for the year 2100 is an increasing of global average temperature, whose impacts in winds, waves, tides, currents and bathymetry will produce real risks of extreme events due to climate changes. Juqueriquere River is Sao Paulo State (Brazil) North Coastline major waterway. Due to minimum channel depths in the coastal bar, navigation is only possible for small leisure crafts and fishing boats and some cargo barges during higher tidal levels. This study case has been evaluated according to the relative sea level and wave climate scenarios forecasting, based on the meteorological recognition patterns of the last decades data for tides and waves. The impact of climate changes is obtained from this knowledge. The main goal of this paper is to have the initial conceptual description about the impacts on the bar navigation conditions of Juqueriquere to obtain guidelines for master nautical plans.
EN
The use of an Analogical Simulator in shiphandling-manoeuvre tests (SIAMA) in waterways constitutes a useful tool for providing improvements in port design and manoeuvring rules, which, when en-hanced with other relevant hydraulic studies of Froudian scale models, is a source of valuable statistical in-formation. The time-scale of physical models fast-time runs complie with the square root of the linear scale, in this study-case the model time was 13.04 times faster than prototype. More than 1500 official tests having been undertaken since 1993 by 13 official pilots of three harbours, for manoeuvring and project optimization in 7 piers, with 10 berths, and radio-controlled ore carriers of 75,000, 152,000, 276,000 365,000, 400,000 and 615,000 dwt. The laboratory facilities belong to the Escola Politécnica of Sao Paulo University, Brazil. The port area studied comprised fairways, turning basins and berths. The ships and tugs were unmanned, with tug performance exerted by air fans.
first rewind previous Strona / 1 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.