Port Structures Research Articles

Potential for architectural adaptation port silos

Post-industrial port structures occupy significant territories and play an important role in the architectural environment of port cities. Constantly changing social needs predetermine the search for new ideas and approaches to the reintegration of the former port territories and structures. The general tendency to preserve the integrity and successive development of the urban environment is the rejection of demolitions, unpromising losses from the standpoint of ecology, culture and economics. Architectural adaptation of a unique historical form (from an individual object to a territory) contributes to its integration into the urban infrastructure; is the art of connecting past and present. The article analyzes the potential of the combined urban planning and architectural value of historical silos as integral elements of port areas, with the aim of their reuse and sustainable development. The catalyst for the search for new ideas for filling, for a vivid imaginative solution of the “space of the future” is the characteristics of port engineering and technical structures (silos, warehouses, berths, cooling towers, etc.), their town-planning value. The overlap of different moments in time stimulates social interaction, forms the “spectacularity of opportunities”, a creative industry. The paper considers the trends and methods of adaptation (transformation, smart reuse) of port territories and silos into a dynamic sustainable environment.

Recent geomorphological evolution of channel bar in Magdalena River (Colombia) due to natural and anthropogenic interferences

The growing establishment of port structures in estuarine regions has resulted in alternated sedimentation patterns and new geoforms. The primary purpose of this study is to understand the recent formation and geomorphological evolution of the fluvial bar in the final portion of the Magdalena River. The geomorphological evolution analysis was made possible using Geographic Information Systems tools, satellite images, and bathymetric data. The studied bar formed and stabilized through anthropic and natural factors such as port structures (obstacles to sediment transport), channel morphology, and natural- and anthropic-caused variation to the sediment supply. The lateral bar formation, adjacent to port structures, began in 2017 with surface runoff accumulating and anchored on the riverbank since 2018. At present, the bar covers 45% of the original river width, and an approximate sediment volume worth 4,000,000 m3 has accumulated. Changes in the navigable channel result in slope modification from 2.02° to 5.36°. The construction of port structures, i.e. new pile bridges, changes the natural sediment flow, because they are obstacles, trapping sediments downstream. This period coincides with the end of a weak El Niño cycle, subsequent to a La Nina period also of low intensity, with reduced precipitation rates resulting in a decrease in flow, and therefore contributing to an increase in sedimentation. The observations suggest that it is crucial to understand the channel bars' morphology and origin to avoid possible economic and social impacts due to the disruptions in navigation.

Experimental study on seismic response of gravity-type quay wall considering input earthquake frequency and excess pore pressure buildup in backfill

In performance-based seismic design of port structures, it is crucial to accurately verify the seismic performance of structures. Therefore, there is an increasing demand for investigation of the seismic behavior of quay walls, considering the comprehensive interaction between the backfill, quay wall, and water. In this study, to evaluate the influence of the earthquake frequency and excess pore pressure buildup in the soil on the seismic responses of a gravity-type quay wall, a dynamic centrifuge test was performed. Four earthquake motions were applied to a quay wall model under saturated soil conditions. The measured records of acceleration responses and pore pressure in the soil and wall displacement showed that the earthquake frequency is strongly associated with permanent displacement of the wall and liquefaction in the soil. Based on time–frequency analysis, the frequency band of the input motion, which mainly contributed to the generation of permanent displacement of the wall, was found. Contrary to the hypotheses of conventional simplified analysis methods, the phase relationship between measured dynamic displacements of the wall and soil, excess pore pressures, and dynamic thrust showed that excess pore pressure buildup in backfill is a crucial factor in determining the dynamic thrust acting on the quay wall.

Development of Small Container Ports: Case Study – Port of Bar

Container ports are just one point on the international transport chain. Therefore, their development is determined by the cooperation of all participants in the transport chain that connects users of transport services with the ports, both economic entities and administration. This paper presents the basic preconditions for development of small container ports and the challenges they face. The Port of Bar was used to study the case. The main goal of this paper is to determine the development steps or phases that small container ports should implement in order to better position themselves on the regional market, i.e. to meet the requirements set by shipping companies. The paper analyzes different types of transport connections with the hinterland as well as a state of port infrastructure and superstructure in relation to ports in the region. The research hypothesis says that the correct sequence of different development steps directly affects the development of small container ports. The methods which will be used in the paper are analysis, synthesis, induction, deduction, generalization and concretization, as well as the meth-od of comparison. The results of the research will provide a new understanding of the issue of development policies of small container ports in relation to available capacities and transport connections. The results can be used by the management structures of small container ports, but also in the work of national bodies in the field of maritime and transport. The research is based on the example of the Port of Bar as well as the ports in the region of Balkans un-til it doesn't take into consideration other small container ports from around the world. Therefore, the obtained results of the research could not be completely generalized. Thus is, this issue requires further research that would consider its various aspects.

Towards a model of port-based resilience against fisher labour exploitation

Fishers have pronounced vulnerabilities to labour exploitation and modern slavery. Regulatory efforts to mitigate fisher labour exploitation through domestic modern slavery legislation, and through the ratification and implementation of The International Labour Organization’s Work in Fishing Convention (C188) have had varying success. This heterogeneity is mainly because the implementation of C188 rests upon ratified states enforcing aligned domestic legislation, and rests also on the supposition that each port state has the resources and capacity to implement these standards within its port networks through enforcement levers and agencies often with varying operational reach and with overlapping jurisdictions. In practice, C188 applies messily and variably in ports. Increasingly ports are cast as fulcrums for addressing labour abuses in fishing, yet policies have struggled to connect together the needs of individual fishers with relevant port structures and services in a meaningful and actionable way. This paper advances a conceptual model for conducting a port-by-port analysis of port communities by appraising site-based assets and dynamics. With this understanding, a port-based and place-specific account of fisher vulnerability and resilience can be constructed. This analysis also considers how regulatory coverage and enforcement can be supplemented by the operationalisation of a multi-factored, multi-scalar consideration of risk determinants. Together this dynamic asset and liability-based model of port resilience can better reflect the variability of port enforcement, capacity, and infrastructure to more effectively assess fisher labour exploitation and identify pathways for improved enforcement.

Using Machine-Learning for the Damage Detection of Harbour Structures

The ageing infrastructure in ports requires regular inspection. This inspection is currently carried out manually by divers who sense the entire below-water infrastructure by hand. This process is cost-intensive as it involves a lot of time and human resources. To overcome these difficulties, we propose scanning the above and below-water port structure with a multi-sensor system, and by a fully automated process to classify the point cloud obtained into damaged and undamaged zones. We make use of simulated training data to test our approach because not enough training data with corresponding class labels are available yet. Accordingly, we build a rasterised height field of a point cloud of a sheet pile wall by subtracting a computer-aided design model. The latter is propagated through a convolutional neural network, which detects anomalies. We make use of two methods: the VGG19 deep neural network and local outlier factors. We showed that our approach can achieve a fully automated, reproducible, quality-controlled damage detection, which can analyse the whole structure instead of the sample-wise manual method with divers. We were able to achieve valuable results for our application. The accuracy of the proposed method is 98.8% following a desired recall of 95%. The proposed strategy is also applicable to other infrastructure objects, such as bridges and high-rise buildings.

Pure Electric Sweeper Performance Analysis and Test Verification of Dust Extraction Port

Purely electric sweepers are widely used in the urban sanitation industry due to their emission-free nature and ease of miniaturisation. The dust suction port is the key to the dust suction system of the sweeper, and improving the design level of the dust suction port of the sweeper can effectively improve the operational performance of the sweeper. Using the company’s self-developed Ruiqing S26 pure electric sweeper as the research object, a CFD (Computational Fluid Dynamics) method was used to analyse the influence of the dust suction port structure parameters (front baffle tilt angle, outlet diameter) and sweeper operation parameters (driving speed, operating pressure) on the dust suction effect of the sweeper, and was verified through real vehicle tests. The results of the study show that changing the angle and outlet diameter results in a change in the flow field characteristics and, consequently, the same change in the removal efficiency, with 65° and 160 mm being the optimum angle and outlet diameter, respectively. The tests investigated the flow field characteristics of the dust extraction opening and the removal efficiency. This study can provide theoretical reference for performance optimisation and parameter matching of the sweeper.

Locally integrated partnership as a tool to implement a Smart Port Management Strategy: The case of the port of Ravenna (Italy)

The modern port structure is configured as territorial system of productive aggregation (hub) of a complex nature, strongly linked to the productive fabric of a larger territory and in close relationship with the context in which the port is physically located. In the development of processes of innovation and improvement of the sustainability of the activities connected to the port, a strong connection is necessary between all the local stakeholders who, each for the functions of their own competence, can activate improvement processes with common objectives. This paper describes a framework for the activation and coordination of a Locally Integrated Partnership (LIP) towards the development of a multi-term Smart Port Management Strategy (SPMS) to support innovation processes in the sustainable and safe management of the port. The methodology was applied to the case study of the port of Ravenna (Italy) where the state-owned areas managed by Port Authority (public authority managing the port area) are limited to 50 mt-width harbour quay, while the remaining areas are owned by private companies. The result was the development and the implementation of the roadmap for the development of the SPMS of Ravenna Port with a multi-stakeholder participatory approach. This process favoured the activation of many public funds to modernize port infrastructure, as well as private investments for the development and dissemination of innovations and for the sustainable use of port area. This has shown how the development and coordination of a local LIP makes it possible to make synergies between stakeholders more effective in accessing financing funds and sharing development strategies aimed at innovation and sustainability. The framework developed and tested to the case study demonstrated the benefits of a participatory and inclusive process in decision-making processes, with a benefit for all the key aspects of sustainability. This process can be used, following step-by-step, as a guideline for other port areas.

Research on the Intake Port of a Uniflow Scavenging GDI Opposed-Piston Two-Stroke Engine

The intake port structure optimization is very important for the uniflow scavenging opposed-piston two-stroke engine, as the intake port structure affects the scavenging efficiency and turbulence kinetic energy and thus further impacts the engine indicated efficiency. This paper aims at improving the indicated efficiency, presenting a comprehensive study on the intake port optimization concerning both scavenging efficiency and turbulence kinetic energy. First, a three-dimensional model based on computational fluids dynamics is established and validated. Subsequently, different numbers of intake ports are compared and analyzed from the perspectives of the scavenging efficiency and turbulence kinetic energy. Furthermore, the double-ports intake structure is selected with the consideration of the compact structure and high scavenging efficiency. Then, the radial angle and width of the double-ports structure are optimized based on the response surface method. The results show that the optimized structure increases the turbulence kinetic energy in relative high scavenging efficiency. The indicated efficiency exhibits a significant increase within the speed range of 1000–4000 rpm and reaches the maximum value of 39.5% around 2000 rpm.

Electron Beam Welding Process of Port Stub of CFETR Vacuum Vessel Sector Mockup

Port structures are important parts of vacuum vessel (VV) in China Fusion Engineer Test Reactor (CFETR), which consists of port stubs and port extensions, mainly provides channels for the installation and maintenance of internal components, such as divertor and blanket, and provides interface for auxiliary heating system, diagnostic system, and vacuum pumping. A 1/8 VV sector mockup with port structures is used to explore the key manufacturing technology of CFETR VV. Electron beam welding (EBW) process development of port structures of 1/8 VV sector mockup is introduced in this article taking the inner shell of upper port stub as an example. Through EBW test and process optimization, the surface formation, microstructure, and mechanical properties of the weld are obtained. On this basis, the EBW of the inner shell of the upper port stub is carried out. After phased array ultrasonic nondestructive testing and laser tracker measurement, the weld quality is excellent, and contour accuracy has reached the technical requirements. This study provides important support for the engineering design and construction of the CFETR.

Seismic performance of a structural concrete pile-wharf connection before and after retrofit

A full-scale precast prestressed concrete (PC) pile-wharf specimen with a T-headed dowel bar connection detail was tested under realistic loading and boundary conditions. The testing program introduced several seismic loading protocols, which were determined from nonlinear dynamic analyses of a typical U.S. port structure subjected to ground motions for various hazard levels. Conventional reversed cyclic loading tests were also conducted on the pile-wharf connection, damaged by seismic loading protocols, before and after retrofit. The specimen showed excellent seismic performance in terms of both strength and ductility. It was confirmed that the lateral drift response of such a PC pile-wharf connection is largely governed by a rigid-body rocking mechanism, with spalling in the pile and deck near the joint region appearing to be a main cause of stiffness degradation. This study also considered a section enlargement technique as an efficient retrofitting method of pile-wharf connections in container port structures. The retrofitted pile-wharf connection (with prior seismic damage) showed higher stiffness and improved capacity, but its deformation capacity (ductility) was inevitably limited by previously accumulated damage along the precast pile (where no strengthening was applied).

Research and Analysis on Cavitation of Different Structures of Cone Valve Ports in Pure Water

In order to study the cavitation problem of the pure water medium hydraulic poppet valve, a three-dimensional model of the poppet control valve under a rated pressure of 31.5MPa was established with the help of Soildworks software, and the poppet valve port model was simplified into a two-dimensional symmetrical model with AutoCAD software. Based on the FLUENT software, the liquid-gas two-phase flow simulation of the cavitation phenomenon in the flow field of the poppet valve is carried out, and the cavitation distribution and intensity change rules of the three valve port structures at three opening degrees are obtained. The results show that for the pure water medium hydraulic cone valve, the cavitation distribution in the new stepped structure is significantly reduced and the strength is significantly reduced under the same opening degree.

System-Wide Seismic Risk Assessment of Port Facilities; Application to the Port of Thessaloniki, Greece

Damages in port facilities during past seismic events have led to widespread direct and indirect losses, with serious impact on the economic, operational, and emergency management of the port itself and, as a consequence, on the related society. Ground shaking is among the most widespread sources of seismic damage to port structures and infrastructure, together with the induced phenomena principally associated with the liquefaction of loose, saturated soils that often prevail in coastal areas. This study presents a methodology for the seismic risk assessment of port facilities which considers the combined effects of ground shaking and liquefaction as well as various interdependencies among port elements, which affect the port’s operation and, consequently, the total risk impact. The methodology, based on either probabilistic or deterministic scenario-based approaches, is demonstrated through an application to the Thessaloniki port, one of the most important ports in Southeastern Europe and the largest transit-trade port in Greece. The systemic risk analysis of the port is carried out using as a performance indicator the reduction in the container and bulk cargo movements affected by the seismic performance of the piers, the waterfront, and container/cargo handling equipment, as well as their interaction with the seismic performance of the electric power system. Two different functionality analyses of the port system are performed, one basic and one less conservative alternative. The results of the probabilistic seismic risk assessment are illustrated in terms of annual probabilities of collapse and loss exceedance curves for each individual port component as well as normalized performance loss for the whole port system for the container and cargo terminal. For the scenario-based deterministic approach, the results are given in terms of risk maps presenting the spatial distribution of damages/losses for all components as well as in terms of the expected loss of performance of the port system. The proposed methodology may provide the basis for an efficient seismic risk management of ports. It may also be adjusted and applied to other port infrastructures in Greece and worldwide considering additional components, interactions among elements, and different earthquake induced hazards.

Relationship between flow field characteristics and dust collection efficiency of sweeper suction port

Urban pollution caused by road particles is widely criticized. The complex and changeable internal flow field of the dust suction port has the greatest influence of the dust suction operation effect. The aim of this paper is to explore the influence law of various influencing factors on the flow field characteristics of the sweeper’s dust suction port, and reveal its influence mechanism on the dust suction efficiency of the dust suction port. The results of the study show that: increasing the width and outlet diameter will change the flow field characteristics, and the dust suction efficiency will change accordingly, 500 mm and 280 mm are the best width and outlet diameter respectively. The increase of driving speed will increase the relative speed between the inlet surface and dust particles, causing dust particles to spill. The increase of negative pressure at the outlet will increase the flow field characteristics, but the dust suction efficiency will stop when it increases to a certain value. A new dust suction port structure is proposed to further improve the dust suction efficiency. This study can provide a reference for the design of the dust suction port.

Mechanism study of natural gas pre-ignition induced by the auto-ignition of lubricating oil

The lubricating oil auto-ignition induced pre-ignition (LOAP) is the most threatening abnormal combustion in natural gas engines. To reveal the mechanisms of the occurrence and the suppressing methods of abnormal combustion in natural gas/diesel marine engines, influence mechanisms of thermodynamic condition, reagent gas composition and the volume of oil droplet on abnormal combustion were investigated by a newly developed visual rapid compression machine (RCM). Experimental results indicate that the auto-ignition of in-cylinder suspended oil droplet can cause the fuel–air pre-ignition. Furthermore, the heated burning residuals of oil droplet can glow to become the ignition source which can induce the pre-ignition. Two factors, total combustion duration and maximum pressure rise rate (PRRmax), are introduced. Shorter total combustion duration and higher PRRmax represent a stronger occurrence tendency of LOAP in the dual-fuel engine. Under the range of reagent gas composition and thermodynamic condition in the dual-fuel engine, rising equivalence ratio (ϕ) and reducing methane number (MN) of natural gas can reduce the total combustion duration by 57% and 41% respectively, and increase PRRmax by about 30 times and 1.9 times. Rising compression temperature and pressure shortens the total combustion duration by 40.7% and 40.1% respectively and increases PRRmax by about 1.3 times and 0.8 times. Reducing oil droplet volume only slightly advances its ignition moment, and has little effect on subsequent natural gas pre-ignition. Based on the result, the most influential factors on the promotion extent of pre-ignition are ranked as: ϕ, MN, temperature, pressure, droplet volume (strongest: reagent gases, moderate: thermodynamic conditions, weakest: droplet volume). Therefore, to prevent the occurrence of LOAP, the existence of in-cylinder local rich natural gas region should be avoided first. Then the high-MN natural gas ought to be applied. The compression temperature and pressure need to be reduced moderately on the premise of ensuring thermal efficiency. Moreover, the small volume oil mist should be avoided to enter into cylinder by optimizing oil injection strategies and scavenging port structures. These findings are beneficial to prevent abnormal combustions and further improve engine power performance.

Ancient Port Structures

This paper aims to compare ancient and modern port structures hoping that the modern can help us in a better understanding of the ancient, with special focus on breakwaters and quay walls. The oldest known port structures are briefly presented. Vertical breakwaters and quays, large concrete blocks, pilae and arched breakwaters, piling walls, cofferdams, rubble mound breakwaters and river training walls are described in the ancient and in the modern world. A few geomorphological aspects of coastal harbours are also reviewed.It is concluded that most natural shelters were used in Roman times, but some major ports have been built in places without any natural shelter, for strategic or economic reasons. Most of today’s concepts for maritime structures were already existing in Roman times and it seems that little progress was made until the 18th c. when large maritime structures started to be built again. The combination of concrete and steel enables modern engineers to build higher, deeper and larger than Roman engineers could dream of, but some modern structures may not last as long as some Roman structures, especially in salt water …

Fender segmentation in unmanned aerial vehicle images based on densely connected receptive field block

Periodic evaluation of port structures including outer walls and berthing structures with fenders is paramount to ensure their safety. However, most fenders are inaccessible on land and inspectors utilize floating boats for inspections. Therefore, this study aimed to develop a fender segmentation system incorporating a vision sensor with deep learning segmentation approach. The semantic segmentation model in an encoder–decoder framework was densely connected through a receptive field block convolution module each with two different dilation rates and classified various types and sizes of fenders efficiently. The images of various types of fenders were assembled and augmented to train the proposed network, and its performance was compared to conventional segmentation models. The trained network was finally applied to unmanned aerial vehicle images and the results showed that fenders were successfully segmented even in the case of the images that include changes in shapes or colors.

A multicriteria decision-making approach to classify military bases for the Brazilian Navy

The Brazilian Navy (BN) has its combatant force concentrated in an area with only one exit to the sea. Brazil has an extensive coast that needs to be patrolled and, in case of any kind of conflict, the BN must be able to defend the sovereignty and interests of the country. For this purpose, it is necessary a robust and decentralized naval force, which allows the fulfillment of its mission. This paper aims to classify the most suitable cities in Brazil to be established as naval bases, through the application of the ELECTRE-MOr hybrid method. Seventeen cities were analyzed, which have an opening to the sea and have a pre-existing minimum port structure. The alternatives were evaluated by specialists from the BN, with more than twenty years of active service, in the light of operational, economic and strategic criteria. As a result, five alternatives were classified as the most indicated to be headquarters for the decentralization of the naval power: Belém/PA, São Luis/MA, Fortaleza/CE, Recife/PE and Aratu/BA. This article presents relevance to academia and society, as it represents the application of a method in the state of the art to support the decision-making process in a significant problem for the sovereignty of Brazil, presenting a methodology that can be applied in problems of tactical, operational, strategic and political levels.

CFD-Based Cavitation Research and Structure Optimization of Relief Valve for Noise Reduction

The cavitation flow of the cartridge pilot-operated relief valve’s main valve port was numerically simulated and studied using Computational Fluid Dynamics (CFD) in our research, and the relief valve structure was modified to decrease cavitation noise. The findings indicate that cavitation in the relief valve occurs mostly downstream of the main valve port and is linked to the wall. Cavitation generation is influenced by the jet at the valve port. The closer the high-speed jet at the valve port is to the valve’s inner wall, the more readily cavitation occurs. Conversely, there is less cavitation. This paper reports the effect of the forms and parameters of the main port structure on the jet angle and the morphology of cavitation. The structure of the spool’s annular groove has a considerable influence on the cavitation attached to the spool wall and the valve sleeve wall, whereas the outlet position of the relief valve mostly impacts the intensity of cavitation near the valve sleeve wall. Based on this, the relief valve’s optimized structure is designed, with which the maximum vapor volume fraction and total vapor volume of the cavitation flow are considerably decreased for various inlet pressures and spool openings. The results of the experiment show that following optimization, the noise of the relief valve drops dramatically, confirming that optimizing the structure has a beneficial impact on decreasing cavitation noise.

AVALIAÇÃO DAS CONSEQUÊNCIAS DO GALGAMENTO COSTEIRO DE 10/11 DE DEZEMBRO DE 2013 NA FRENTE URBANA DO CONCE-LHO DE SANTA CRUZ, ILHA DA MADEIRA

The expansion and consolidation of urban areas along the coast lead to the exposure of a large number of anthropic elements to sea storm events. It is with the aim of identifying and classifying the consequences of coastal overtopping that we analyse the recent storm surge of 10/11 December of 2013 which affected the urban coastal fringe of the city of Santa Cruz, on the south coast of Madeira Island. Therefore, the atmospheric conditions of wind intensity and atmospheric pressure are analysed and is characterised the direction of the waves and their maximum height, as well as the tide variation. After the oceanographic and meteorological characterization, it´s identified and evaluated the structural damage on the coastal zone and classified the functional consequences on the port structures affected by overtopping. The quantitative analysis of atmospheric and oceanographic data supports that this overtopping is a green water type resulting from an extratropical storm arising from the rapid reduction of atmospheric pressure and an average wind velocity of 30 km/h, affecting approximately 1600 meters of the coastal area of Santa Cruz. The qualitative analysis of the consequences shows that the port structures suffered severe to catastrophic consequences and dysfunction of their normal activities. The most affected areas are at the extremes of the urban front, registering reduced to insignificant consequences, in the intermediate area. Thus, it shows areas of greatest exposure, and areas that had presented seriously to severe damages, which can be highlighted in future episodes.