RISK AND SAFETY LEVEL ASSESSMENT OF SHIP – BRIDGE COLLISION

Bridges located on maritime and inland waterways are defenseless objects of infrastructure. One of their main features is the restriction of navigation channels, both vertically and horizontally, while navigation conditions may often be challenged by unpredictable currents and whirlpools. A great threat to people and vehicles on or near the structure occurred in case of a collision with ships and the destruction of bridges. Also, the consequences of such accidents are considerable financial expenses, where the cost of the bridge is usually much more than the cost of the vessel itself. The article addresses the issue of types, factors, causes and consequences of ship-bridge collision accidents. In spite of the modern level of development in the maritime industry such accidents occur annually, thus this problem is considered to be relevant nowadays. It is necessary to take measures to increase the safety of navigation in appropriate zones. The article presents the procedure for assessing the level of safety and the stages of identifying risks by determining the probability of a collision with bridge spans, supports and other structures, also identifying the most defenseless places, as well as the possible consequences of such damage (ship, city, environment). In addition, the paper considered the methods of protecting the bridge from collision and methods for reducing navigational risk. The results of the research are the development of the recommendations for avoiding possible dangers, mitigation of consequences, and reducing risks of vessel-bridge collision. It is proposed to form an “intellectual” zone in the navigable water area under the bridge to minimize the risks and consequences of an emergency. As a basic concept, it is recommended to use foreign and domestic experience in implementing the e-navigation strategy in the coastal zone and in the operational VTS areas. The article describes the implementation of modern marine technologies, such as virtual navigation aids and technologies of additional reality, which will significantly improve monitoring of the environment. Therefore, this introduction will reduce the risk of an emergency. Ensuring the full spectrum of available methods is necessary to determine risk and protect bridges from accidents. Such an approach shall allow not only to assess the risk of ship-bridge collision, but also to introduce additional active control elements during navigation in dangerous zones.

CONTROL OF TRANSPORT AND TECHNOLOGICAL SYSTEM OF A SEA PORT

the transport and technological system (TTS) of a seaport serving the industrial-agricultural East Ukrainian region. In the course of controlling processes, much attention is being paid to the analyses of performance indicators, high-quality and efficient management organization, clear interaction of structural divisions as well as uniformity of work performers. The paper is devoted to studying the evolution of the concept of “controlling”, features of the development of this method in relation to the operation of processes and objects of seaports in Ukraine against the background of the competitive environment escalation, deregulation of cargo traffic, and the availability of subrogation equipment. The theoretical system of controlling the work of the TTS of the seaport is made up of effectometrics. The theoretical concepts of "process controlling" and "object controlling" were further developed. The criteria for the effectiveness of the system control of a transport company are determined, which is considered to be highly necessary in order to assess the company’s expenses. Practical measures with reference to the application of the method for controlling the functioning of the TTS in a seaport, which serves the industrial and agricultural region, have been developed.

PERSPECTIVE METHODS OF DIVERGENCE OF VESSELS AND ANALYSIS OF THEIR EFFICIENCY

The article is devoted to the analysis of the most perspective and effective locally-independent methods of divergence of vessels for forming of the system of the automatic warning of collisions, providing safety of perspective autonomous vessels. Development of method of estimation of efficiency of methods of divergence of vessels, which characterizes the degree of safety of completion of process of divergence of vessels, is offered, since the moment of discovery of situation of dangerous rapprochement. The stages of process of decision-making divergence of vessels of necessity are considered at their rapprochement and choice of strategy of divergence. It is shown that a decision-making process contains the following stages: control of environment, including relative position and parameters of relative motion, exposure of situation of rapprochement of vessels, estimation of degree of danger of rapprochement and choice of strategy of divergence. Analytical expressions for formalization of the offered stages of process of decision-making divergence of vessels of necessity are resulted. It is shown that depending on the degree of danger of situation of rapprochement, it is necessary to choose strategy of divergence, coming co-ordination of maneuvers of the drawn together vessels from, foreseen ColReg. Thus character of maneuver of divergence is also determined by the value of situation indignation. As a rule, application of standard maneuver of divergence is foreseen, and in the situation of excessive rapprochement of vessels, in order to avoid the collision it is necessary to use the maneuver of urgent divergence. As the index of efficiency of the analytical collision avoidance systems vessels probability of safe completion of process of divergence, which is work of probabilities of successful finish of stages of process of decision-making on the choice of strategy of divergence, is offered. For the system of the automatic warning of collisions the methods of divergence with one dangerous target are offered by the change of course or speed of ship and with two dangerous targets by the combined maneuver of the repeated change of course of ship. After the preliminary analysis the perspective most effective methods of the mentioned types of maneuvers of divergence were offered. For the operative choice of parameters of maneuver of divergence of ship with a target the regions of impermissible values of parameters of deviation and region of acceptability parameters of deviation and output are offered. For the case of choice of maneuver of divergence of ship by the decline of speed the active or passive braking offers the method of forming of region of impermissible speeds and calculation of its scopes. In the situation of dangerous rapprochement of ship with two targets for the operative choice of parameters of maneuver of divergence of ship in work it is suggested to form the region of acceptability successive courses of deviation.

IMPROVING CONSTRUCTIVE AND TECHNOLOGICAL CONNECTING JOINTS OF REINFORCED CONCRETE PONTOON WITH A TRANSVERSE DIAPHRAGM AND A METAL TOWER IN A FLOATING COMPOSITE DOCK

The analysis of the known technical decisions in dock construction field, rationalizing production resources at composite docks construction is given. It is established that the available solutions do not specify the recommendations for lowering the metal content in the reinforced concrete pontoon of composite floating docks. As a result of the conducted research, the design of floating composite docks was improved by reducing sets in the reinforced concrete pontoon. The rationality of a pontoon design construction without installation of frames, floors, and beams under towers is substantiated. Technological recommendations for the transverse partitions installation between the inner boards in 4 spaces, i.e. in 3 meters in contrast to the classical design in which the distance between the partitions is 1.5 meters, were described. The analysis of the design features of the reinforced concrete pontoon connecting joints with the transverse diaphragm and the metal tower of the floating composite dock is carried out, the difficulties that arise are described. The design and technological recommendations for the construction of the reinforced concrete pontoon joints with the transverse diaphragm and the metal tower have been developed. The floating dock construction sequence and technological operations ensuring concrete’s strength, water tightness and frost resistance at intersection joints are described. Solutions that increase the local adhesion of concrete to cross-shaped parts and prevent its exfoliation have been developed. The traditional scheme of the composite dock construction and a structural joint of a metal tower with a reinforced concrete pontoon is given. The composite dock construction scheme and the construction scheme of the joints of the reinforced concrete pontoon with the transverse diaphragm and the metal tower, which are designed for the construction of floating composite docks with reduced metal content in the pontoon, have been improved.

GENERATION OF NANO-FILLED EPOXY-POLYESTER COMPOSITE MATERIALS FOR PROTECTION OF ELEMENTS OF VESSEL TECHNICAL MEANS

The influence of nanofillers on thermophysical properties of epoxy-polyester composites has been investigated in the work. The filler content (oxidized nanodisperse additive and pyrogenic silicon dioxide) has been varied within q = 0.02…1.0 pts.wt. per 100 pts.wt. of epoxy oligomer ED-20. It has been discovered that the introduction of the oxidized nanodisperse additive in the amount of q = 0.05…0.08 pts.wt. into the epoxy-polyester binder leads to an improvement in the thermophysical properties of the composite. Value of heat resistance (according to Martens) increased from Т = 335 К (for the epoxy-polyester matrix) to T = 346 K at the content of oxidized nanodisperse additive of q = 0.075 pts.wt. Introduction of q = 0.05 pts.wt. of oxidized nanodisperse additive allows to obtain improved values of the temperature coefficient of linear expansion in different temperature ranges: in the region ΔT = 303…323 K – α = 1.0 × 10-5 K-1, in the region ΔT = 303… 373 K - α = 1.9 × 10-5 K-1, in the region ΔT = 303… 423 K – α = 3.4 × 10-5 K-1. It has been determined that the composite material has also improved its heat resistance (according to Martens), which is T = 347 K and the minimum thermal coefficient of linear expansion at the content of q = 0.05 pts.wt. of pyrogenic silicon dioxide nanofiller. Values of the temperature coefficient of linear expansion were: α = 1.0 × 10-5 K-1 in the region (ΔT = 303… 323 K), α = 1.9 × 10-5 K-1 (in the region ΔT = 303… 373 K), Δα = 3.4 ×× 10-5 K-1 (in the region ΔT = 303… 423 K), α = 8.4 × 10-5 K-1 (in the region ΔT = 303… 473 K). It is recommended that in order to form a composite material with improved thermophysical properties to protect the elements of ship technical equipment, it is advisable to introduce the pyrogenic silicon dioxide nanofiller in the amount of q = 0.05 pts.wt. into the epoxy-polyester binder.

MODIFIED EPOXY MATRIX FOR VEHICLE PROTECTION: ADHESIVE AND PHYSICAL-MECHANICAL PROPERTIES

The significance of application of the polymer composite materials in current technologies has been proven, since they have been demonstrating high performance parameters, offering improved adhesion failure resistance, enhanced mechanical and thermophysical properties which as a consequence enables their application under both ambient and elevated temperatures. The purpose of the current work is to investigate the influence of the phthalimide modifier on the adhesive and physico-mechanical properties of epoxy composite materials and protective coatings based on them. The ED-20 epoxy diane oligomer has been taken as the main component for the binder in the formation of epoxy materials. Polyethylene polyamine hardener has been used for the crosslinking of epoxy compositions. Phthalimide has been taken as a modifier. The molecular formula of the modifier is: C8H5NO2. The molar mass of phthalimide is 147.13 g/mol. It has been proven that with the introduction of the phthalimide modifier in the amount of 2.0 pts.wt. into 100 pts.wt. of ED-20 epoxy oligomer, the material which offers the following properties is being built up: adhesive failure resistance at breaking off - 47.7 MPa, residual stresses - 1.1 MPa. Compared to the parent epoxy matrix, these properties demonstrate an improvement of the adhesive failure resistance at breaking off by 1.9 times, and in addition to the above, the residual stresses are being reduced by 1.3 times. The composite obtained may be reasonably taken in the form of a matrix when building up an adhesive layer for protective coatings. It has been experimentally proven that in order to build up the materials which would offer improved cohesive properties, it is necessary to use a composition of the following makeup: ED-20 epoxy oligomer (100 pts.wt.), polyethylene polyamine hardener (10 pts.wt.), phthalimide modifier (0.25 pts.wt.). Compared to the parent epoxy matrix, the formation of that kind of a material provides an improvement of the following indicators of physical and mechanical properties of composites: bending critical stresses - from 48.0 MPa to 62.1 MPa; impact value - from 7.4 kJ/m2 to 14.7 kJ/m2. Note that the elasticity coefficient of this material is being reduced compared to the parent epoxy matrix from 2.8 GPa to 2.2 GPa. The composite obtained may be reasonably taken in the form of a matrix when building up the surface layer for protective coatings.

CLASSIFICATION CHARACTERISTICS OF UNMANNED TETHERED UNDERWATER SYSTEMS AS A COMPONENT OF IMPROVING THE EFFICIENCY OF THEIR DESIGN

The design stage is considered to be rather resource-intensive in the entire process of creating marine robotic technology. Therefore, the applied scientific task of reducing the resource costs for those processes is of high interest. Among other things, the time consumed for design stage has to be reduced by determining the design characteristics at an early stage of design. The approach considered to reduce such costs involves structuring the classification features of tethered underwater systems in such a way as to simplify the selection and justification of design solutions at the stage of preliminary system design. For design engineers of underwater equipment, the list of classification features of tethered self-propelled and those towed underwater systems has been suggested. The list is based on a system approach and is structured according to material, energy, information and operational (functional) criteria. All of that enables performing the comparative assessment of existing systems upon key indicators and formalizing the processes of their synthesis at early stages of design. To demonstrate the capabilities of the system approach, the generalized algorithm for the organization of design works using the system of classification features of tethered self-propelled and towed underwater systems at the early stages of their design. The algorithm involves the formation and structuring of many classification features of such systems as the initial stage of the process of making effective design decisions in the early stages of design of underwater robotics. It has been revealed that putting in use the classification features system in question, enables deploying minimal project resources to make reference to the relevant databases and decide on already-existing artifact projects and select out of those available in the underwater equipment market key components and parts of underwater systems which would satisfy the requirements of the technical task of implementing the tethered underwater systems. That would significantly reduce the prime cost of design works and enhance the competitiveness of domestic science-based achievements in the markets of marine robotics.

THE FORMATION OF THE CONTAINER VESSEL LOADING PLAN

The paper considers the location of containers when loading the ship taking into account the sequence of ports of unloading to provide access to the required consignments, as well as the fact that the intermediate states of loading the ship when passing between ports must meet the requirements of its maritime safety. Therefore, a method of forming a plan for loading a container ship, which provides for the placement of containers in the cargo space, which meets the requirements for landing, stability and overall longitudinal strength of the vessel. Expressions have been given to calculate the increments of static moments relative to the axes of the vessel, which arise as a result of receiving batches of containers for loading the vessel. It is noted that as a result of containers loading, the trim of the vessel should be in the range from 0 to -2,0 m. From the specified interval the trim which corresponds to placement of containers satisfying requirements of longitudinal durability has been chosen. Therefore, for loading the vessel, procedures for determining the limit values of the moments that provide the ship's trim from 0 to -2.0 m have been considered. To do this, the formulas for calculating the average weight of the batch of containers located in each of the cargo spaces designated for loading batch containers have been obtained, and expressions for determining the weight of cargo in each cargo space depending on its location along the length and height of the vessel. The procedure of joint consideration of the containers placement of different batches of loading the vessel on the parameters of landing, stability and overall longitudinal strength of the vessel has been considered. To do this, the component of the required static moment has been determined depending on the share of the weight of the party in the total weight of the vessel. To confirm the correctness of the suggested method with the help of a computer program, it was calculated to load the ship "Sky Jameni", which can accept containers in eight holds and on their hatches. The vessel is characterized by a maximum average draught of 13.0 m and a maximum displacement of 68,318 tons. The loading plan of the above-mentioned vessel has been formed with the help of the developed program by three container parties. The first container party includes 1900 containers weighing 28800 tons and it has been loaded in 10 cargo holds; the second one consists of 600 containers weighing 9000 tons, has been located in four holds, and the third one weighing 7200 tons and consists of 552 containers has been located in three holds. The considered loading satisfies the requirements to maintain the seaworthiness of the container carrier.

IMPROVING THE CLEANING EFFICIENCY OF THE DIESEL ENGINE PURGE AIR COOLER

In order to increase the mass of the air charge, one has to increase its density. Therefore, the density of the air may be increased by increasing the air pressure and reducing its temperature. The temperature of the purge air is being decreased in the air cooler. With the lapse of time, its performance efficiency drops due to the contaminant pollution of heat transfer elements, which as a consequence, leads to the diesel engine power reduction. The established procedure for cleaning the air cooler does not ensure a complete cleaning of heat exchangers, especially in hard-to-reach places, and manual mechanical cleaning is rather time consuming and requires engine cutoff over a protracted period of time. Thus, improving the efficiency and simplifying the complexity of the air cooler cleaning procedure is considered to be an urgent task to complete. In order to reduce those shortcomings, the modernization of the air cooler cleaning system is being considered. The upgrade being suggested involves an installation of auxiliary atomizing devices on both sides of the cooling element, i.e., in those places where the air cooler is being polluted the most. The purge air temperature increase leads to a decrease in the engine power, increased fuel consumption and accumulation of deposits in the exhaust manifold and flue pass, which consequently may contribute to a spontaneous combustion. Taking into consideration the demand for regular cleaning procedure of the cooling element, the serial system is time consuming. In addition to cleaning by means of atomizers, it also involves systematic disassembly of the cooler and manual cleaning of the elements. The modernization being suggested allows to increase the cleaning efficiency of the blower air cooler of the diesel engine by installing additional atomizers of detergent near the side surfaces of the cooling element. Modernization procedure is not a complicated one and its implementation is possible on existing vessels by the engine crew taking into account the necessity of a long-term stopover of the vessel for maintenance and repair. The solution is universal and may be implemented on ships with the gas-turbocharged engines with purge air cooling system. The application of an upgraded system will also reduce the complexity of the cleaning procedure of the air cooler cooling elements by avoiding manual mechanical cleaning of hard-to-reach cooling surfaces.