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In this paper, a numerical study is presented to investigate wave force on the connections of main parts of a side-anchored straight floating bridge concept for the Bjørnafjorden fjord crossing. The floating bridge is supported by 18 pontoons, and three groups of mooring lines are employed to restrain the bridge against horizontal loads and increase its transverse stiffness. The created wave forces at the connections of pontoon-column and column-girder of the floating bridge considering the effects of short-crested and long-crested waves, varying wave direction, hydrodynamic interaction between pontoons, and mooring system are analyzed. It is found that short-crested and long-crested waves depending on their direction decrease or increase the wave forces on the joints. Considering that the effect of hydrodynamic interaction between pontoons can increase or reduce the wave forces and moments created in the joints, which means the neglect of the hydrodynamic interaction effects between the pontoons to simplify the modeling of this type of floating bridge, may be unacceptable. Moreover, the results showed that the bridge mooring system does not merely reduce the wave forces and moments at joints along the bridge.

Reinforced concrete (RC) pontoons have been widely used as floating foundations to support various structures. However, pontoons are under the threat of accidental collisions from passing ships and...

In this paper, three curved floating bridge concepts with a uniform span of 500 m and different radii of curvature are proposed for the crossing of the coastal waters in Singapore. The bridge girder is supported by 4 pontoons along the bridge length and the two ends are connected to the shore. Three different girder cross-sections are considered. Static analysis is first carried out considering the bridge's self-weight, water current forces and various tidal conditions. Next, eigen value and regular wave analyses are performed to assess the effect of bridge radius, cross-sectional rigidity and end connection on the bridge behaviour. Based on the results, several bridge configurations are selected for further study. Finally, irregular wave analysis is carried out to investigate the realistic bridge performance under operational and extreme environmental conditions. Conclusions are drawn based on the simulation results. Recommendations on the design parameters for further investigations are made.

Herein, numerical predictions of the dynamic response of an existing floating pontoon bridge are compared with the measured dynamic response. Hydrodynamic coefficients that describe the fluid-structure interaction and the wave transfer functions are obtained by applying linear potential theory. The results obtained from the hydrodynamic analysis are combined with a beam model of the bridge in a finite element method (FEM) framework to enable stochastic response prediction through the power spectral density method. The standard deviations of the predicted accelerations are compared with the standard deviations of the measured accelerations, and the overall quality of the prediction model is discussed. Predictions with sea states related to the serviceability limit state (SLS) and ultimate limit state (ULS) conditions used in design of the bridge are emphasized. To investigate the behaviour more in depth, a measurement segment is chosen and predictions of the displacement response power spectral density due to excitation characterized by the recorded sea surface elevation are compared with those obtained from the corresponding response measurements. A decent agreement is obtained for both cases when using the model as it is and with waves as the only excitation source, but significant discrepancies are present, in particular, for the torsional components. By including preliminary contributions from wind action and relying on a model optimized against measured modal parameters, a satisfactory agreement is obtained. The effect on the response of an uncertain structural damping is also quantified and concluded to be significant within realistic damping levels.

The object of the study is a pontoon link, where the role of the bearing structure is performed by non-standard pipes. Construction of surface bridges is widely used in bridge construction and is an essential part of the development of transport infrastructure of our country and abroad. In the case where it is not possible to build capital or low-water bridges, surface bridges or ferry crossings are used. Built-up bridges are very convenient to use in the construction of capital bridges, when the main course of the route is blocked instead of temporary stationary bridges. In order to compare the application of the developed solution, an approximate calculation of the cost of the pontoon was made. Analysis of costs in the market of analogues showed that the cost of only the bearing structure of a pontoon of similar load capacity based on plastic pipes, will be much higher than the cost of pantone out of non-standard. The study examined the possibility of using non-standard pipes for the construction of weld bridges. Non-standard pipes are a promising material for construction of weld bridges due to buoyancy, low cost, such pipes are easily available raw materials.

Floating bridges are the practical answers for intersection enormous waterways with unordinary depth and exceptionally soft bottom where conventional piers are impractical. This paper describes experimentally the stability of bed material underneath the floating bridges under different hydraulic conditions introduced regarding flow discharge, tailgate water depth, the bridge length and the bridge draft for different loads over the bridge. Two distinctive bed materials are utilized to characterize the bed morphological changes. One hundred and sixty-eight tests are completed and the results are differentiated to the basic case where no bridges are introduced. The outcomes reveal that the particles size of bed material and the bridge draft are the dominant parameters that influence the bed morphology and flow attributes.

In 636 CE, Roman and Arab contingents met at the river Yarmouk. After days of fighting, the Roman army suffered a disastrous defeat. The provinces of Palestine and Syria, which had been reconquered from Persian occupation only a few years prior, were again lost to enemy forces. The emperor Heraclius (610–641), who had coordinated the defense in person, left Syria in haste. A passage in Nicephorus’ Breviarium covers what happened in Constantinople in the aftermath of the battle: It tells a seemingly strange tale of Heraclius being so afraid of water that he would not enter the capital until a bridge of boats was built over the Bosporus. In scholarship this tale is often reproduced uncritically. Deconstructing the passage, I argue that the image of a mentally frail Heraclius is an instance of political satire that exposed the emperor’s weak position and ridiculed his attempts to cope with the destabilizing consequences of Roman defeat. When seen from a structural perspective, it becomes clear that Heraclius was not afraid of water but intended the bridge of boats to serve as a triumphalist statement at a moment when the situation in Constantinople threatened to slip out of his control.

The article presents an analysis of the use of a floating bridge within a large urban conurbation in an emergency situation. The analysis is associated with a failure of the system transferring sewage from left-bank Warsaw to the ‘Czajka’ treatment plant located on the right-bank of the Vistula River. It includes checking the load bearing capacity of a typical floating bridge structure constructed using the PP-64 pontoon system supporting two pipelines transporting sewage across a wide water obstacle.

We propose an approach for floating bridge installation and operation. A floating bridge aims to carry heavy vehicles, trucks, and people over a body of water. However, bridge installation and operation are mainly performed by humans regardless of adverse conditions, such as active combat or disaster occurrence. For installing and operating floating bridges under such conditions, we devised a solution based on control system design and automatic installation. The floating bridge system is controlled and positioned by a power propulsion system that is attached to floating units of the bridge. An optimal control system based on state estimator, which is designed using a robust control framework, is applied to install and operate the bridge. A simulation analysis and experiments demonstrate the effectiveness of proposed method on a bridge system model comprising five floating units.

As a bridge envisaged in the future of tunnel crossings, the submerged floating tube bridge (SFTB) is a floating bridge, submerged at a defined position under the water level. The closed cross-sect...

This paper proposes a test method to evaluate the operability of railway vehicles crossing floating bridges. To inspect the dynamic response of the floating bridge to the railway vehicle, the test setup was separated into wave tank and shake table tests. A scaled-down model representing a unit length of the floating bridge span was manufactured for the wave tank test. Several harmonic waves were artificially created and the displacement at the center above the top surface was measured using an optical position sensor. The response of the floating structure was analyzed to extract the relative amplitude versus the input wave for sway, heave, and roll. The harmonic motions using these responses were simultaneously used as input signals for a six-degree-of-freedom shake table. The scaled-down bogie model ran back and forth repeatedly on the railway placed on the shake table. The acceleration measured from the railway vehicle was analyzed to evaluate the running safety and behavior. All tests were performed without allowing derailment and showed sufficient margin to satisfy the running safety and behavior standards. The proposed test method was successfully conducted and showed a remarkable potential to evaluate the operation of railway vehicles on floating bridges under various wave conditions.

The article deals with the experience of the 901st separate pontoon bridge company of the Armed Forces of Ukraine in completing the task of demining the territory at the United Nations Peacekeeping Mission in Angola (UNAVEM III) from January 1996 to February 1999. involvement of the Ukrainian contingent in this mission, the main tasks that were entrusted to it, as well as the conditions and results of mine clearance activities.The article shows that in the absence of active fighting one of the main threats to the life of Ukrainian peacekeepers in the peacekeeping mission was mines, un- exploded shells and other explosive objects.The mission of the 901st Pontoon Bridge Company was to have the following main tasks: restoration of engineering infrastructure in areas of responsibility; reconstruction of roads, construction of temporary bridges and pontoon-bridge crossings over rivers to provide the population with the necessities of products and organization of construction of stationary bridges.Mine clearance work was complicated by the lack of reliable information on the scale of the mined areas, as well as specific locations and the number of mines and explosive objects installed.The experience gained in Angola has also shown that a comprehensive and effective solution to the contamination of contaminated sites is possible through the use of international assistance and experience, in particular by private com- panies dealing with humanitarian demining.

On the eve of the Ottoman-Russian War of 1768-1774 there was a belief that the Ottomans were losing their bridge-building skills as they had not fought in the Danube region for nearly 30 years. This study principally aims to test whether this was really true. The method for testing it lies in the secondary aim of the study: to holistically reveal the floating bridge activities carried out by the Ottoman Empire on the Danube River and beyond during the war. Within the scope of these two aims, the Ottoman chronicles and archive sources were examined. As a result of the review, it was observed that the Ottomans assigned a bridge official called an "emin" to organize this work, and this official organized widespread activities in order to bring raw and finished materials, as well as skilled and unskilled personnel from near and distant environments to bridge sites. Bridge activities were carried out in Isaccea. Silistra and Tutrakan on the Danube, as well as on the Dniester, Pruth and Oltu rivers beyond the Danube. Despite some problems and the lack of engineering experience in bridging activities, the Ottomans appear to have performed floating bridging activities in this period at an appropriate level.

The dual inverter multilevel converter is characterized by a elementary structure using two well-known three-phase bridge inverters supplied by two independent DC sources. However, it can be supplied only by a single DC source if one of the bridges uses just a floating DC capacitor. In this case the control is more complex since it is also required to ensure the capacitor voltage regulation. Besides this, if a fault in one of the switches is also considered, the operation of the converter in fault operation mode becomes even more complex. This paper presents a vector voltage modulator that in addition to track the reference of the output AC voltages, also allows the capacitor voltage regulation of the floating bridge. The capability of this modulator to function properly the converter in fault tolerant mode under an inverter open switch will also be analyzed. This analysis will allow to verify that the proposed control and modulation strategy presents inherent fault tolerant capability to open switch fault, since it does not require any fault detection algorithm or change in the control or modulation strategy. The capability and operation of the proposed vector voltage modulator will be verified through several simulation studies

A model for oblique wave interaction with a floating bridge in the presence of a submerged breakwater and a trench is developed. The breakwaters and trenches are considered to be of trapezoidal and circular types. The performance of these undulations in bottom bed are analyzed in detail for reflecting waves and reducing resulting forces on bridge. The analysis is performed by utilizing solutions derived with the aid of modified mild-slope equation in the undulated bottom region and of eigenfunction expansion in uniform bottom region. Significant changes are found in wave reflection and forces due to consideration of these undulations in bottom bed as compared to those in the case of uniform bottom everywhere in fluid region. The present study shows certain range of wave incident angles at which the breakwaters and trenches perform effectively in reflecting waves and thereby reducing forces. A complementary connection is justified between reflection of waves and consequent forces on bridge. Moreover, critical wavenumbers and angles where zero reflection occurs are found in shallow and intermediate water depth. The critical values are found to lead an increase in forces and for these values appropriate gap lengths between bridge and breakwater or trench, width of breakwater and trench are explored. Phase shift in reflection and forces is observed due to the inversion of undulated profiles. Within a periodic value of the distance between the breakwater/trench and the floating bridge, optima in wave reflection occurs. In addition, the maxima in wave reflection is associated with the minima in wave forces acting on the floating bridge. The findings from the present model are likely to be useful in understanding the role of breakwaters and trenches in engineering applications.

To ensure the stability of the bottom under the floating bridges according to the worst conditions, our study aims to determine the height and width and bearing the floating bridge to ensure the safety of origin with a high security factor. Our study determines the amount of damage under the floating bridge to be treated by a treatment method. We have used a practical model for a water channel and standard dimensions cut by the floating bridge connecting the two ends of the channel and when studying the erosion under the floating bridges and the possibility of maintaining the floating bridges without damage to the structure and perimeter of the bridge (bridge width, maximum load, bridge height, water depth in the channel with a factor Security This study examines the effect of floating bridges on the bottom by designing a model of a channel with a floating bridge and selecting a variable earth and sand floor. We conducted one hundred and sixty-eight experiments to examine the five variables (water depth in the channel, bridge width, loads on the bridge, soil type) Bottom, flow). We observed the effect of these five variables on topography of the bottom of the floating bridge. Experiments were conducted without a bridge and we observed erosion after laying the bridge, we noticed the erosion and sediment that occurred before and below and after the floating bridge and the effect of the bridge on it. We observed the type of positive and inverse relations between the variables mentioned. We took the loads on the bridge, the width of the bridge, the depth of the water and the drainage with a safety factor, as well as ensuring that the appearance of the channel and maintain the geometry of the channel. We put floating loads on the floating bridge to see a load. We used several models to view the floating bridge and made the water depth in the channel change more than once. We also made three different discharges. Finally, we used two types of soil and we recorded the durability and the worst conditions. The effect discharge, by (100% .64%, 45%) The velocity in the sandy soil changes (100%, 42%,38%) and the velocity in clay soil changes (100%,59%,41%) As well as change the width of the bridge by (100%, 85%,71%)velocity changes by (80%,82%,100%) for sandy soil and the ratio of clay soil to (90%,95%,100%) As well as weight change by (100% ,83%,66%)the rate of velocity in the sandy soil to (100%,78%,61%) also change the velocity in clay soils to (100%,68%,62%) as well as depth change (100%,87%,75%)The speed in the sandy soil changes to (50%,75%,100%) and also changes in clay soils by (71%,78%,100%) Thus, we have a knowledge of the rates of change and the effect of each variable on velocity. Therefore, we can draw up a plan to address erosion and sedimentation in the watercourse. Moreover, identify the expected challenges of (overload, flooding, deterioration, foot and aging as well as the structural strength of the bridge gradually decreasing with the foot.

To solve the optimization problems in port planning and operation management, particle swarm optimization, Cat mapping, and cloud model were combined. A Chaos Cloud Particle Swarm Optimization (CCPSO) algorithm was proposed. It was used in port planning management. Its application in port throughput forecasting and berthing and pontoon bridge allocation was explored and studied. By analyzing the mixed properties of Cat maps, the chaotic characteristics of the map were good. Thus, it was introduced into the hybrid optimization algorithm for chaotic perturbation of poor individuals in a particle swarm. The selection of the parameter combination of the Gauss-SVAR model was troublesome. The parameter combination of Guass-vSVR model was optimized by CCPSO algorithm, and the Guass-vSVR-CCPSO model was obtained. Using CCPSO algorithm, a discrete berth bridge allocation model was established. The results showed that the particle feasible integer processing module was developed. Therefore, a new method for multi-objective discrete berth shore-bridge allocation based on CCPSO algorithm is feasible.

The conceptual design of any floating bridge requires detailed investigations of its dynamic responses to achieve safe and reliable structures. Floating structures are subject to dynamic excitations due to wind or wave loads. Low structural damping is expected for long-span floating structures, and additional environmental damping is therefore much appreciated. The most important dynamic loads are wave and wind loads, where wave radiation damping, viscous drag damping, and aerodynamic damping strongly influences the overall response. Compared to hydrodynamic damping, aerodynamic damping covers a broader frequency range, stretching over multiple eigenmodes. Therefore, aerodynamic damping represents an important contribution and is the main topic of this publication. A short overview of available self-excited load models is presented. Different models are tested numerically and compared to the wind tunnel test.

Modular floating systems are structures used both for the army and the civilian population needs. They enable construction of temporary water crossings, for example, in place of permanent out of service bridges or objects renovated due to mechanical and other damages. Special features of this type structures include the possibility of using them regardless of the depth and terrain conditions of the water crossings. The requirements currently set for such structures force their modernization as well as search for innovative solutions. They should allow easy and quick assembly-disassembly of the structure, and have a low weight and dimensions to facilitate transport as well as minimize storage space. These requirements are met by a pontoon construction based on an innovative cassette designed in Poland (Military University of Technology). A single cassette contains a high-strength elastic coating pontoon which, after filling with air, allows obtaining the regulation of buoyancy force, appropriate depending on the type of water crossings. The paper deals with testing the load capacity of a pontoon bridge composed of repetitive segments-cassettes with adjustable immersion. Numerical models of a single floating cassette and a group of connected cassettes constituting ferries or sections of a pontoon bridge are also presented in the paper. The methodology for load capacity tests and selected test results of such floating objects are discussed. Multibody numerical methods and FEM (Finite Element Method) are used for dynamic and static analysis of multi-component floating systems. Selected field tests and laboratory stand tests conducted with the use of the strength machine are applied to validate the various type of numerical models.

Floating bridges are considered as a solution to the deep-water crossing. In this study, dynamic behaviors of a curved floating bridge, which consists of a girder, columns, and pontoons, are analyzed in the time-domain in waves, winds, and currents. This type does not have mooring lines so that deep-water installation can be much easier than conventional bridges and floating bridges with mooring lines. The key factor is, therefore, to have good global behaviors. In the frequency domain, we computed hydrodynamic added mass, radiation damping, wave excitation forces by using a 3D diffraction/radiation program. Time-domain simulations were further conducted under different loading conditions. Second-order wave-excitation and dynamic wind loads induce significant lateral motions of the girder since a wave-dominant-frequency range is close to its natural frequencies while the first-order wave-excitation force plays an important role in the girder's vertical motion.

Owing to the structural characteristics of floating-type structures, they can be effectively applied to overcome the limitation of conventional long-span bridges in deep water. Unlike cable-supported bridges with fixed towers, floating cable-supported bridges show relatively large displacements and rotations under the same load because of floating towers, moreover, the difference in the support stiffness causes differences in the behavior of the superstructures. In addition, the risk of overturning is greater than in conventional floating offshore structures because the center of gravity of the tower is located above the buoyancy center of the floater. A floating cable-supported bridge in which the tether supports the floating main tower is directly influenced by the tether arrangement, which is very important for the stability of the entire structure. In this study, according to the inclined tether arrangement, the outer diameter of the floater, and the buoyancy vertical load ratio (BVR), the static behavioral characteristics of the long-span cable-stayed bridges with floating tower are evaluated through nonlinear finite-element analysis. When the intersection of the tension line of the tether and a pivot point of the tower coincide, the tethers can no longer resist the tower&rsquo, s rotation. For this reason, a large displacement occurs to equilibrate the structure, and further increases as it approaches the specific slope, even if it is not exactly the specific tether slope. The analytical model of this study indicates that, in terms of increasing the rotational stiffness of the main tower, it is advantageous to increase the floater diameter until a BVR of 1.8 is reached and to increase the axial stiffness of the tether from a BVR of 2.0 or higher.

The interaction between oblique water waves and floating bridge in the presence of a vertical partial flexible permeable barrier is studied under the assumption of the linear water wave theory in finite water depth. The associated mathematical problem is handled for a solution using the least-squares approximation method. The reflection and transmission coefficients, free surface elevation, wave force acting on the bridge and barrier are computed to study the effects of various wave and structural parameters for three different edge conditions. The study reveals that wave reflection decreases with an increase in porosity, and a reverse pattern is found in the case of wave transmission. As the normalized spacing between the barrier and the floating bridge increases, the reflection coefficient follows a periodically oscillatory pattern. Furthermore, it is noticed that regardless of the barrier configurations, the wave reflection increases for an increase in the angle of incidence. It is also found that the surface-piercing barrier is more efficient than the bottom-standing barrier as a wave barrier. Moreover, the results indicate that by placing a porous flexible barrier at an appropriate position, the wave force on the bridge can be reduced significantly.

As a potential option for transportation applications in coastal areas, curved floating bridges with a same small specified rise to span ratio of 0.134, supported by multiple pontoons, are investigated in this paper. Two conceptual curved bridges are proposed following a circular arc shape with different span lengths (500 and 1000 m). Both bridges are end-connected to the shoreline without any underwater mooring system, while the end-connections can be either all six degrees of freedom (D.O.F) fixed or two rotational D.O.F released. Eigen value analysis is carried out to identify the modal parameters of the floating bridge system. Static and dynamic analysis under extreme environmental conditions are performed to study the pontoon motions as well as structural responses of the bridge deck. Deflections and internal forces (axial forces, shear forces, and bending moment) are thoroughly studied with the variation of the span length and end support conditions in terms of the same specified small rise-span ratio. The ratio of axial force to horizontal bending moment are presented. From the study, it is found that the current parameters for the bridge are relatively reasonable regarding responses. However, the small rise-span does not provide enough arch effects. A higher rise-span ratio or stiffer bridge cross-sectional property is preferred, especially for the long bridge. In addition, the flexible end connections are preferred considering the structural responses at the end regions.

Fallujah pontoon bridges were not merely crossings installed to join the west and east banks of the Euphrates River, they also represented a vital link in the land transport network that connected Iraq to the outside world in the eastern Mediterranean and beyond. With the growth of Fallujah’s economic role on the international commercial map in the late 15th and early 16th centuries, the pontoon bridges gained a huge commercial and military significance (demonstrated by the Ottomans’ repeated attempts to install such pontoon bridges along the Euphrates banks near Fallujah). The local authorities in Iraq regulated the toll tax imposed on crossing bridges and using ferries in Fallujah. However, toll tax regulation was considerably developed under the Hashemite monarchy. This is the key focus of this paper, which evaluates the development of the toll tax regulations, investigating unpublished official documents produced during the Hashemite monarchy. Keywords: Fallujah, Modern History, Pontoon bridges, Toll tax regulation.

Several computer programs exist to handle general multipurpose offshore structural analysis of slender structures subjected to wave loading, although they have not been developed with the specific purpose of floating bridge global analysis in mind. Owing to the inherent complexity of a floating bridge structure, this poses a valid concern regarding the accuracy in the calculated response. Normally, the intended computer program is validated against experiments, but in the case of extremely long floating bridges the size limitations of existing ocean basins necessitate the use of hybrid testing where the computer program is a part of the method to obtain the true value from the experiments. It is, therefore, crucial to obtain an overview of how sensitive the numerical results are to inaccurate user inputs, approximations introduced in the theory, and the software implementation of the theory, as well as possible settings that the user does not have access to. An extensive comparison between two commonly used commercial computer programs in the offshore industry is presented in the present paper for a global analysis of a floating pontoon bridge concept. The comparison includes modal properties as well as deterministic and stochastic structural response owing to wave loads based on coupled hydroelastic time domain simulations. First- and second-order wave loads are included in the comparison as well as viscous drag. The study indicates reasonable agreement in the response acquired by the two computer programs and highlights the consequences of differences in some of the input parameters. This material may be downloaded for personal use only. Any other use requires prior permission of the American Society of Civil Engineers.

This paper is concerned with a computational study on the hydroelastic response of a long, straight and side-anchored fjord-crossing floating bridge accounting for the wave-current interaction. The effect of this interaction on a single bridge pontoon is investigated by using the three-dimensional potential solver VERES3D. The frequency-dependent hydrodynamic coefficients and excitation force transfer functions are presented and compared with WAMIT results where the current effect is ignored. Based on the frequency domain results, an approach to account for the wave-current interaction in time domain analysis is proposed. Next, a generic straight and side-anchored floating bridge model is put forward to examine the stochastic structural responses in the time domain. For the purpose of comparison, the bridge responses under waves and current without interaction are also investigated. This study attempts to quantify the wave-current interaction effect on the structural responses of a floating bridge and provide useful recommendations and suggestions to researchers and engineers for their study of similar structures.

The present paper provides a comparison between the numerical and experimental response for a generic floating pontoon bridge structure, thereby also serving to quantify the inherent uncertainties associated with both types of models. The numerical model is updated based on an initial comparison of static response and modal properties. The natural frequencies of the hydro-elastic model are calculated by also accounting for the frequency-dependent added mass of the pontoons. The model is then used to compare with the experiments for wave- and current-induced responses. The numerical model is subsequently applied for the purpose of quantifying the effect of uncertainties in the experimental model properties and setup. A clear description of the model details is given for reproducibility and experimental data is made available for future references. The computer program used to create the numerical model has previously been validated for a wide range of different offshore structures, but such an assessment has not been made in connection with application to floating bridges. The objective of the present paper is accordingly to contribute to an improved understanding of hydro-elastic modelling capabilities e.g. in connection with future hybrid testing of such bridges that are characterised by significantly extended span-lengths. This is an open access article distributed under the terms of the Creative Commons CC-BY license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Singapore is a tiny island city-state with only about 710 km2 of land space. Land has always been a precious resource in Singapore. Creation of space has therefore been an important objective for the country. This paper presents the recent research and development activities pertaining to the use of floating structures for both industrial and recreational applications in Singapore. These include the research and development studies on floating hydrocarbon storage facility, floating bridge and modular multi-purpose floating structures as well as the development and construction of floating wetlands and floating solar farms.

The regulatory method for calculating the load capacity of floating bridges of a hinged scheme from two-support ferries does not take into account the effect of the cross beams on the joint work of the main beams. To take into account the effect of transverse beams on the joint operation of main beams, it is proposed to introduce the coefficient of longitudinal load distribution between transverse beams. To determine the coefficient, a finite element model of the floating bridge span was built. While the test of the crossing deflections of beams, fibre linear tensile strain were measured, the lower chords of main girders in the monitored cross sections and the deflections of the ice cover. Controlled sections were selected on the principle of occurrence of maximum forces in them. It is advanced and confirmed by test methods calculation to cargo-carrying capacity floating bridge joint scheme from two-supporting ferry on base of the account of the influence of the transverse beems to collaboration main beems by been entering the corrective factor in formula accounting bending moment.

Mooring systems are important structural components of very long floating bridges. They effectively limit the transverse motions of the bridge under environmental loads. They also add viscous hydrodynamic damping to the entire system. The safe and economical design of mooring systems is thus important but also challenging especially when the wave conditions are inhomogeneous. In this paper, a computational study is carried out to investigate the responses of the mooring lines for a 4.6 km long fjord crossing floating bridge accounting for inhomogeneous wave conditions. Based on the structural responses, this study also attempts to evaluate the fatigue damage in the mooring lines by using different fatigue analysis methods. The accuracy of the spectral methods is examined by comparison with the conventional rainflow cycle counting algorithm. Numerical studies are conducted to obtain an indication of the effect of various wave inhomogeneities on the fatigue damage in the mooring lines. DOI: 10.1016/j.oceaneng.2020.108304. 0029-8018/© 2020 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license

In this paper, we present a numerical study on the hydroelastic response of a 4.6 km long fjord crossing floating bridge subjected to wave loads. The bridge is straight in design and supported by 35 pontoons along its full length. To limit the response to horizontal loads, four clusters of deep water mooring lines are engaged to increase the transverse stiffness of the bridge. Owing to the very large span across the fjord, inhomogeneity in the wave field exists. This study examines the various effects of inhomogeneous wave loads on the dynamic responses of the floating bridge. These include the spatial variations of the wave direction, significant wave height and peak period as well as the coherence and correlation of waves along the entire length of the floating bridge. For the purpose of comparison, the dynamic bridge responses under homogeneous wave load cases are also studied. In addition, the effects of wave load components and short-crestedness are presented and discussed. /© 2020 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

The current research aims to suggest some solutions to Aljadriya intersection nearby Baghdad University in order to reduce traffic congestion crisis at this intersection. It is assumed that shifting to more sustainable modes of transport, and the opening of closed traffic routes will significantly improve traffic performance. The traffic movement characteristic has been studied in this intersection depending on some previous research. And as a result, there has been many troubles shown in the level of service for this intersection reached (F level). And by suggesting a group of solutions representing by; first: providing enough space to extend the TOD transmission line from western side (Jadriya bridge) towards the eastern side (Karrada). Second is to open a secondary floating bridge that parallels Aljadriya bridge which works on prepayment, and by applying these solutions we can reduce the traffic congestion from 7–28% depend on strategies which applay.

The aim of this paper is to investigate the influence of floating bridge motion on bus driver’s ride comfort and road grip for the straight concept solution across Bjornafjorden. For this investigation 3 degrees of freedom (DOF) bus model is defined for numerical simulation. Bus model has been excited by vertical motion of the bridge for four different bus speeds. Ride comfort has been assessed according to method and criteria proposed by International ISO 2631/1997 standard. For road grip assessing Dynamic Load Coefficient (DLC) has been used. It has been concluded that on floating bridge ‘little uncomfortable’ ISO 2631 criteria is reached at lower bus speed comparing to stationary ground road. Higher values of DLC for the case of floating bridge points out higher variation in vertical tyre forces (worse road grip). For bus speed at 90 km/h, DLC for floating bridge is approximately 0.08 which is 7% higher value comparing it to the case of stationary road.

A light rail passenger transportation system is being built in Seattle, WA, USA, that traverses Lake Washington over an existing pontoon bridge. The water level in Lake Washington changes throughout the year. This causes rotations of the transition spans, which are needed at each end of the bridge to carry traffic between the fixed, land-based structure, and the floating structure. This paper explains a novel method, the Curved Element Supported Rail (CESuRa) system, that provides rails with the ability to undergo joint rotations at the ends of the transitions spans without risk of damage, while maintaining full vertical support of the track across the joint. The geometric characteristics on which it depends for proper operation, considerations that must be accounted for when using the system for other applications in the future, and an overview of the implementation of the system on the floating bridge are discussed.

Looking for a way to span the roughly 20 mi long Lake Washington, engineers constructed the Murrow Bridge, the largest floating bridge in the world at the time, and the Mount Baker Ridge Tunnel.

In this paper the three phase open end winding IM drive is designed and controlled using a fuzzy control based multilevel inverter with SVM technique is proposed. To overcome the disadvantages of PI controller, in this project we are using the fuzzy controller. The fuzzy controller rules are analyzed very easily, because of it is a human decision making system. The traditional dual inverter having two dc sources the cost and size is might be high, so to overcome this we use the proposed method with single dc voltage source. The main objective of the proposed method is to eliminate the transformer. To achieve the multilevel output voltage waveform with three levels a dc voltage ratio 2:1 is used. The space vector PWM is used to control the switching states of dual multilevel inverter. The fuzzy controller implementation cost is less and more precise. The simulation results are used to analyze the proposed method with fuzzy controller.