Increase In Traffic Volume Research Articles

CONGESTION EFFECTS OF AUTONOMOUS TAXI FLEETS

Fleets of shared Autonomous Vehicles (AVs) could replace private cars by providing a taxi-like service but at a cost similar to driving a private car. On the one hand, large Autonomous Taxi (AT) fleets may result in increased road capacity and lower demand for parking spaces. On the other hand, an increase in vehicle trips is very likely, as travelling becomes more convenient and affordable, and additionally, ATs need to drive unoccupied between requests. This study evaluates the impact of a city-wide introduction of ATs on traffic congestion. The analysis is based on a multi-agent transport simulation (MATSim) of Berlin (Germany) and the neighbouring Brandenburg area. The central focus is on precise simulation of both real-time AT operation and mixed autonomous/conventional vehicle traffic flow. Different ratios of replacing private car trips with AT trips are used to estimate the possible effects at different stages of introducing such services. The obtained results suggest that large fleets operating in cities may have a positive effect on traffic if road capacity increases according to current predictions. ATs will practically eliminate traffic congestion, even in the city centre, despite the increase in traffic volume. However, given no flow capacity improvement, such services cannot be introduced on a large scale, since the induced additional traffic volume will intensify today’s congestion.

SoftEdgeNet: SDN Based Energy-Efficient Distributed Network Architecture for Edge Computing

The volume of data traffic has increased exponentially due to the explosive growth of IoT devices and the arrival of many new IoT applications. Due to the large volume of data generated from IoT devices, limited bandwidth, high latency, and realtime analysis requirements, the conventional centralized network architecture cannot meet users requirements. Intensive real-time data analysis is one of the major challenges in current state-ofthe- art centralized architectures due to the ubiquitous deployment of different types of sensors. To address the current challenges and adhere to the principles of architectural design, we are proposing a SoftEdgeNet model, which is a novel SDN-based distributed layered network architecture with a blockchain technique for a sustainable edge computing network. At the fog layer, we introduce an SDN-based secure fog node architecture to mitigate security attacks and provide real-time analytics services. We are also proposing a flow rule partition, and allocation algorithm at the edge of the network. The evaluation result shows our proposed model allows for a significant improvement of the interactions in real time data transmission. In terms of the ability to mitigate flooding attacks, the bandwidth is maintained above 9 Mb/s until the attack rates exceed 2000 PPS in the hardware environment and the bandwidth remained almost unchanged in the software environment. In the case of scalability of the proposed model, our proposed algorithm has performed better and proceeded linearly with the increase in traffic volume.

Overcoming degradation in spatial multiplexing systems with stochastic nonlinear impairments

Single-mode optical fibres now underpin telecommunication systems and have allowed continuous increases in traffic volume and bandwidth demand whilst simultaneously reducing cost- and energy-per-bit over the last 40 years. However, it is now recognised that such systems are rapidly approaching the limits imposed by the nonlinear Kerr effect. To address this, recent research has been carried out into mitigating Kerr nonlinearities to increase the nonlinear threshold and into spatial multiplexing to offer additional spatial pathways. However, given the complexity associated with nonlinear transmission in spatial multiplexed systems subject to random inter-spatial-path nonlinearities it is widely believed that these technologies are mutually exclusive. By investigating the linear and nonlinear crosstalk in few-mode fibres based optical communications, we numerically demonstrate, for the first time, that even in the presence of significant random mixing of signals, substantial performance benefits are possible. To achieve this, the impact of linear mixing on the Kerr nonlinearities should be taken into account using different compensation strategies for different linear mixing regimes. For the optical communication systems studied, we demonstrate that the performance may be more than doubled with the appropriate selection of compensation method for fibre characteristics which match those presented in the literature.

Exploring Traffic Congestion on Urban Expressways Considering Drivers’ Unreasonable Behavior at Merge/Diverge Sections in China

The mechanisms of traffic congestion generation are more than complicated, due to complex geometric road designs and complicated driving behavior at urban expressways in China. We employ a cell transmission model (CTM) to simulate the traffic flow spatiotemporal evolution process along the expressway, and reveal the characteristics of traffic congestion occurrence and propagation. Here, we apply the variable-length-cell CTM to adapt the complicated road geometry and configuration, and propose the merge section CTM considering drivers’ mandatory lane-changing and other unreasonable behavior at the on-ramp merge section, and propose the diverge section CTM considering queue length end extending the expressway mainline to generate a dynamic bottleneck at the diverge section. In the new improved CTM model, we introduce merge ratio and diverge ratio to describe the effect of driver behavior at the merge and diverge section. We conduct simulations on the real urban expressway in China, with results showing that the merge section and diverge section are the original location of expressway traffic congestion generation, and on/off-ramp traffic flow has a great effect on the expressway mainline operation. When on-ramp traffic volume increases by 40%, the merge section delay increases by 35%, and when off-ramp capacity increases by 100 veh/hr, the diverge section delay decreases about by 10%, which proves the strong interaction between expressway and adjacent road networks. Our results provide the underlying insights of traffic congestion mechanism in urban expressway in China, which can be used to better understand and manage this issue.

Simulation Analysis on Optimal Merging Control of Connected Vehicles for Minimizing Travel Time

This study examined a cooperative merging control methodology for connected vehicles to optimize traffic flow without considering a traffic priority/non-priority at intersections. A cellular automata microsimulation was constructed to examine the methodology. It was used for simulating the traffic condition and for predicting a future conflict between two vehicles at a T-junction or cross-junction. Optimum vehicle control patterns of the two vehicles for avoiding the conflict and minimizing the total travel time of all vehicles on the road network was examined. Simulation results demonstrate that the proposed methodology can reduce total travel time and that the control patterns become more diverse as the traffic volume increases.

Flexural performance of high strength engineered cementitious composite-steel beam coupling with shrinkage load

With increase of traffic volume, orthotropic steel deck stiffened with a cementitious composite overlay becomes a popular deck type in long-span bridge. In this paper, flexural performance of high strength engineered cementitious composite (HSECC)-steel composite beam, especially the effect of internal curing of HSECC on cracking load, ultimate load, deflection and crack opening under load, is studied by experiments. In the test program, five mixtures of HSECC, including four mixtures internally cured (IC) with pre-wetted calcined particles and one mixture with ordinary curing (OC), are used. The test results show that cracking and ultimate bending load of internally cured HSECC-steel composite beam is greater than that of ordinarily cured composite beam. Deflection at cracking and peak load of internally cured composite beam is larger than that of the beam with ordinarily cured HSECC. Internal curing can also improve the ability of crack opening control after cracking. Reduction on shrinkage stress resulting from shrinkage of the cement composite layer in the structure should be responsible for the positive effect on bending performance of HSECC-steel composite beam.

Automated vehicles: exploring possible consequences of government (non)intervention for congestion and accessibility

ABSTRACTAcademic research on automated vehicles (AVs) has to date been dominated by the fields of engineering and computer science. Questions of how this potentially transformative technology should be governed remain under-researched and tend to concentrate on governing the technology’s early development. We respond in this paper by exploring the possible longer-term effect of government (lack of) intervention.The paper tests the hypothesis that a “laissez-faire” governance approach is likely to produce less desirable outcomes in a scenario of mass uptake of AVs than would a well-planned set of government interventions. This is done using two prominent themes in transport policy – traffic flow and accessibility – in a scenario of high market penetration of Level-5 automated vehicles in capitalist market economies. The evidence used is drawn from a literature review and from the findings of a set of workshops with stakeholders.We suggest that a laissez-faire approach will lead to an increase in traffic volume as a result of a growing population of “drivers” and a probable increase in kilometres driven per passenger. At the same time, the hoped-for increases in network efficiency commonly claimed are not guaranteed to come about without appropriate government intervention. The likely consequence is an increase in congestion. And, with respect to accessibility, it is likely that the benefits of AVs will be enjoyed by wealthier individuals and that the wider impacts of AV use (including sprawl) may lead to a deterioration in accessibility for those who depend on walking, cycling or collective transport.We consider the range of possible government intervention in five categories: Planning/land-use; Regulation/policy; Infrastructure/technology; Service provision; and Economic instruments. For each category, we set out a series of interventions that might be used by governments (at city, region or state level) to manage congestion or protect accessibility in the AV scenario described. Many of these (e.g. road pricing) are already part of the policy mix but some (e.g. ban empty running of AVs) would be new. We find that all interventions applicable to the management of traffic flow would also be expected to contribute to the management of accessibility; we define a small number of additional interventions aimed at protecting the accessibility of priority groups.Our general finding is that the adoption of a package of these interventions could be expected to lead to better performance against generic traffic-flow and accessibility objectives than would a laissez-faire approach, though questions of extent of application remain.In our conclusions, we contrast laissez-faire with both anticipatory governance and “precautionary” governance and acknowledge the political difficulty associated with acting in the context of uncertainty. We point out that AVs do not represent the first emerging technology to offer both opportunities and risks and challenge governments at all levels to acknowledge the extent of their potential influence and, in particular, to examine methodically the options available to them and the potential consequences of pursuing them.

Using Eye Movement Data Visualization to Enhance Training of Air Traffic Controllers: A Dynamic Network Approach

The Federal Aviation Administration (FAA) forecasted substantial increase in the US air traffic volume creating a high demand in Air Traffic Control Specialists (ATCSs). Training times and passing rates for ATCSs might be improved if expert ATCSs’ eye movement (EM) characteristics can be utilized to support effective training. However, effective EM visualization is difficult for a dynamic task (e.g. aircraft conflict detection and mitigation) that includes interrogating multi-element targets that are dynamically moving, appearing, disappearing, and overlapping within a display. To address the issues, a dynamic network-based approach is introduced that integrates adapted visualizations (i.e. time-frame networks and normalized dot/bar plots) with measures used in network science (i.e. indegree, closeness, and betweenness) to provide in-depth EM analysis. The proposed approach was applied in an aircraft conflict task using a high-fidelity simulator; employing the use of veteran ATCSs and pseudo pilots. Results show that, ATCSs’ visual attention to multi-element dynamic targets can be effectively interpreted and supported through multiple evidences obtained from the various visualization and associated measures. In addition, we discovered that fewer eye fixation numbers or shorter eye fixation durations on a target may not necessarily indicate the target is less important when analyzing the flow of visual attention within a network. The results show promise in cohesively analyzing and visualizing various eye movement characteristics to better support training.

Application of Trajectory Data for Investigating Vehicle Behavior in Mixed Traffic Environment

The research work reported here investigates driving behavior under mixed traffic conditions on high-speed, multilane highways. With the involvement of multiple vehicle classes, high-resolution trajectory data is necessary for exploring vehicle-following, lateral movement, and seeping behavior under varying traffic flow states. An access-controlled, mid-block road section was selected for video data collection under varying traffic flow conditions. Using a semi-automated image processing tool, vehicular trajectory data was developed for three different traffic states. Micro-level behavior such as lateral placement of vehicles as a function of speed, instant responses, vehicle-following behavior, and hysteresis phenomenon were evaluated under different traffic flow states. It was found that lane-wise behavior degraded with increase in traffic volume and vehicles showed a propensity to move towards the median at low flow and towards the curb-side at moderate and heavy flows. Further, vehicle-following behavior was also investigated and it was found that with increase in flow level, vehicles are more inclined to mimic the leader vehicle’s behavior. In addition to following time, perceiving time of subject vehicle for different leading vehicles was also evaluated for different vehicle classes. From the analysis, it was inferred that smaller vehicles are switching their leader vehicles more often to escape from delay, resulting in less following and perceiving time and aggressive gap acceptance. The present research work reveals the need for high-quality, micro-level data for calibrating driving behavior models under mixed traffic conditions.

Using multiple paths in SCTP to reduce latency for signaling traffic

The increase in traffic volumes as well as the heterogeneity in network infrastructure in the upcoming 5G cellular networks will lead to a dramatic increase in volumes of control traffic, i.e., signaling traffic, in the networks. Moreover, the increasing number of low-power devices with an on-off behavior to save energy will generate extra control traffic. These increased traffic volumes for signaling traffic, often generated as bursts of messages, will challenge the signaling application timing requirements on transmission. One of the major transport protocols deployed for signaling traffic in cellular networks is the Stream Control Transmission Protocol (SCTP), with support for multiple paths as well as for independent data flows. This paper evaluates transmission over several paths in SCTP to keep the latency low despite increasing traffic volumes. We explore different transmission strategies and find that concurrent multipath transfer over several paths will significantly reduce latency for transmission over network paths with the same or similar delay. Still, over heterogeneous paths, careful, continuous sender scheduling is crucial to keep latency low. To this end, we design and evaluate a sender scheduler that considers path characteristics as well as queuing status and data flows of different priority to make scheduling decisions. Our results indicate that by careful dynamic sender scheduling, concurrent multipath transfer could lead to reduced latency for signaling traffic irrespective of path or traffic characteristics.

Safety Evaluation of Geometric Design Criteria: Intersection Sight Distance at Unsignalized Intersections

A Policy on Geometric Design of Highways and Streets, 6th Edition, (publisher: AASHTO), provides design criteria for minimum sight distances, including intersection sight distance (ISD). An understanding of the relationship between ISD and safety at stop-controlled intersections is needed, with potential applications of this knowledge to both performance-based design and substantive road safety management practices. To establish this relationship, crash, traffic, and geometric data were collected from 832 two-lane minor unsignalized intersection approaches in Ohio, and Washington. The data were analyzed using a cross-sectional study design to quantify the relationship between safety and ISD. The analyses indicated that the expected number of target crashes are associated with available ISD. Target crash frequencies increase as available ISD decreases. Results suggest that ISD is associated with expected crash frequency in a non-linear fashion. The sensitivity of the expected number of target crashes to changes in ISD is highest when ISD is shorter, and decreases as ISD increases (i.e., the safety benefit of increasing ISD from 300 to 600 ft is substantially larger than the safety benefit of increasing ISD from 1,000 to 1,300 ft). The results also suggest that the impacts of ISD on crash frequencies vary as a function of the major road two-way annual average daily traffic and the major road speed limit. The sensitivity of the expected number of crashes to changes in ISD increases as both traffic volume and speed limit increase. Crash modification functions for each of the target crash types were estimated using the regression models.

Comparative Performance Evaluation of Effects of Modifier in Asphaltic Concrete Mix

This article describes how the gradual increase in traffic volume, poor design and construction practices and lack of attention to maintenance during the last few decades has caused an accelerated and continuous deterioration of the road network in Pakistan. The above factors are among the main causes of pavement failures, especially rutting. Rutting failure occurs when the pavement surface exhibits wheel path depressions caused due to softening of asphalt. In this article, different modifications were used in bitumen to reduce rutting, and compared it with unmodified bitumen. Low Density Polyethylene (LDPE) and crumbed rubber were used as modifiers. The compacted asphalt mixes were tested for resistance to rutting using wheel tracking machine at 25°C and 55°C temperatures. From this research, it is concluded that the crumbed rubber modified bitumen is a better option than LDPE, especially at high temperatures. However, conventional (unmodified) bitumen gives satisfactory performance at low temperatures.

A Theoretical Framework for Understanding Pedestrian Behaviour Attributes Based on Spatial Interaction

Current trend shows there is an exponential increase in rail traffic passenger volume in Malaysia, causing authorities to be aware in improving the pedestrians’ facilities and safety. Kuala Lumpur Sentral Station (KLSS) is the largest transportation hub in Malaysia and, as of May 2017, the user reaches up to 180,000 users daily. In this contribution, a theoretical framework is presented to understand the pedestrians’ behaviour attributes at rail transit terminal based on pedestrians’ spatial interactions. The Distinct Element Method (DEM) will be employed to model the dynamics of pedestrian’s crowd behaviour. The validated crowd dynamics model will be demonstrated in evacuation capacity estimation in KLSS. Evacuating people quickly and safely can greatly reduce casualty and economic losses. As for this contribution, more concern is on the spatial interaction of pedestrian at the RTT and the proposed framework. This framework paper will describe the flow in details on conducting the study of spatial intersection.

Experimental evaluation of crumb rubber and polyethylene integrated modified asphalt mixture upon related properties

Due to the dramatic increase in traffic volume, asphalt pavements deteriorate gradually with the high-temperature rutting and low-temperature thermal cracking as two main failure modes. This paper focuses on the integrated modification of bituminous binders and asphalt mixtures with the aspect of improving the performance of asphalt pavement at both high and low in-service temperatures. The recycled crumb rubber (CR) and polyethylene (PE) were chosen as polymer agents in order to modify the bitumen property. Analysis on the rheological performance of modified bitumen indicated the addition of CR decreased the bitumen creep stiffness at low-temperature which in turn reduced the brittleness and cracking risk. Meanwhile, the addition of PE increased the bitumen stiffness at high-temperature which resulted in improved rutting resistance. With respect to the integrated modified bitumen, the addition of CR and PE cooperatively improved the bitumen properties at both high and low temperatures. In terms of the asphalt mixture, PE contributes to the permanent deformation resistance at high in-service temperature while the CR enhanced the flexibility at low in-service temperature. The integrated modified mixture prepared with CR and PE obtained significantly enhanced performance at both high and low in-service temperatures. Consequently, utilisation of these two recycled materials is able to improve the pavement properties reached to or even better than those prepared with styrene-butadiene-styrene modified bitumen.

A method of hold baggage security screening system throughput analysis with an application for a medium-sized airport

The hold baggage security screening (HBSS) is one of the essential steps in a pre-flight operation process. With the continuous increase in the overall air traffic volume, the development of security screening (and control) technologies, and the changes in applicable regulations of law, the structure and equipment of HBSS systems require frequent upgrades. In order to make good, effective decisions about the upgrades, airport management requires tools for quantitative determination of their results. The aim of this work is to analyse the HBSS system throughput. The analysis can serve as an aid in airport management in on-the-go solving of operating issues and making decisions about HBSS upgrades. A mathematical model was established for the analysis in the form of a coloured timed Petri net, and implemented in a computer-aided solution. It was a microscale simulation model, in which every piece of hold baggage is localised in time and with a resolution of a single belt conveyor. The computer-simulated experiments completed with the model helped (i) determine the actual throughput of the HBSS system operated at the Katowice International Airport, (ii) determine the effects of disturbances on the HBSS system operation, (iii) evaluate the impact of the time windows available to SSO (security screening operators), the SSO's work organisation and the efficiency of automatic security screening on the HBSS system throughput, and (iv) determine the throughput for specific alternative variants of the HBSS organisation, including doubled automatic security screening. These results allow a conclusion, that a four-level HBSS system, which includes automatic security screening, two SSO screening levels based on X-ray imaging, and manual control is an HBSS solution adequate for a regional medium-sized airport. It was also found that, given the growth of airport facility complexity and area, an increase of HBSS throughput is viable rather not by improving the capacity of specific HBSS components, but by deploying them in parallel processing lines. The highest throughput growth potential lies in parallel deployment of automatic security screening lines.

Impact of car free day on foyer building environment

Universiti Teknologi Malaysia has been organizing the car-free day (CFD) on the campus since 2016 among others to reduce air pollution and improve environmental awareness among campus community. This study aims to determine the effect of the car-free day on two foyer’s building environment with three objectives; to determine the variation of traffic volume, to assess the CO2 concentration and noise level variation, and to evaluate the impact of traffic volume variation on CO2 concentration and noise level in building. Two different locations of building are selected; inside and outside CFD. Traffic volumes on the nearby roads are counted and CO2 concentration and noise level at the foyer of the selected building are recorded i.e 8:00-3:00 pm, both during CFD and NCFD at each location. The significant impact of traffic compositions on CO2 and noise level variation are evaluated by using the statistical method including T-test, simple and multiple regression analysis with R2 and ANOVA test, with significant level of 5%. The results show that the implementation of CFD has good and adverse impacts on building environment. The good is CFD reduces traffic volumes up to 80%, and significantly reduce both CO2 and noise level at building located in car free zone. At the selected site, the reduction of CO2 is 13.57±4.87 ppm per hour and the reduction of noise level is 4.7±1.74dBA. During CFD, the concentration of CO2 is significantly governed by the volume of the bus while noise level is significantly correlated with the total volume of traffic. Reduction of noise level is significantly related with decrease of volume of lorries on road. On the other hand, CFD causes adverse impact on building environment as there is significant increase in traffic volume, noise level and CO2 concentration at a selected site outside of CFD zone. The traffic volume increase up to 82% which dominantly characterized by car and motorbikes. These results in increment of noise level by 1.77 ±1.37 dBA and sharp increase of CO2 more than 9999 ppm after the first 3 hours of CFD and remain the same values until end of CFD which may be not acceptable for human comfort. Result from this study shows that CFD improve the environment in building located at CFD zone but worsen the building environment in NCFD.

Evaluation of the Traffic Performance Measure for Exclusive Motorcycle Lane at Merging Section

Exclusive Motorcycle Lane (EML) is defined as a roadway meant exclusively for motorcycles or can be stated as motorcyclists who are compelled by law to use it and other vehicles are prohibited by law from using it. It is physically separated from the mainstreams carriageway and is grade separated from the main carriageway at intersections, interchanges or points of conflicts. Merging is one of the parts of way that motorcycle deceleration the speed from main stream lane to enter the Exclusive Motorcycle Lane (EML) with safe. The urban expressways in Malaysia have serious problems regarding the safety, efficiency and comfort ability at merging sections of an EML because of the insufficient geometric due to limited land and the right of way design configuration condition. The increase of traffic volume and demand lead towards the degradation of motorcyclist performance while on their wheels. This research is performed in order to achieve the objectives, i.e. to obtain and analyze local empirical data, such as flow rate, headway and speed on exclusive motorcycle lane at merging section that reflects on the local traffic condition on Federal Highway Route 2, and to obtainregression modeling that relates to Flow Rate with regards to the Headway 1-3, Time Mean Speed and Length of Merging Ramp section, Lm on the merging section of EML and merging ramp section. Tworegression models have successfully been performed with R-Sq 94.8 % for EML section and 31.1 % for merging ramp section. Its also highlighted the attributes of EML.

Traffic emission control through gasoline automotive engine mixture enhancement

Transportation networks today are witnessing a dramatic increase in traffic volume that emits large amounts of pollutants into the atmosphere. Many environment‐friendly technologies are introduced recently to reduce vehicles' emissions. It is possible to obtain a homogeneous fuel–air mixture in the internal combustion engines under ideal conditions, but it is hard to have control on this mixture in the abnormal conditions. Based on the engine's working conditions, the mixture, sometimes, becomes rich and at other times it might become chemically correct. In this work, a new spiral shape device is used to enhance the mixture homogeneity and to maintain a correct fuel–air mixture. The spiral device works on enhancing the mixture through dividing the fuel particles into smaller ones. The device splits the particles to the largest number possible so it can mix better with the air and evaporate quickly in the combustion chamber. Results showed that use of the new device reduced the percentages of carbon monoxide (CO), the carbon dioxide (CO2) and the hydrocarbon. The mixing process is also improved as it is clear from the air–fuel ratio. © 2017 American Institute of Chemical Engineers Environ Prog, 37: 761–765, 2018

EFFECT OF FLY ASH CONTENT IN MBC BONDER FOR SUSTAINABLE CFRP RETROFIT

The rehabilitation and strengthening of reinforced concrete structures have been attracting increasing attention due to various factors including increase in traffic volume and weight, structural aging and environmental impact. Various techniques such as grouting, guniting and external post-tensioning are being used to retrofit or strengthen deteriorated members. With recent developments in the application of fiber composites in structural engineering, externally bonded Fiber Reinforced Polymer (FRP) system has become one widely used repair techniques because of its durability and long-term cost-effectiveness. In the FRP bonded retrofit technique, epoxy is often used as the bonding material. Because of environmental impact and health issues, construction sector is always looking for sustainable alternative bonding materials for FRP retrofit. A new trend on using Mineral Based Composites (MBC) has garnered the attention for a possible alternative to replace the use of harmful epoxy in FRP retrofit. MBC is formed by mixing the cement with some other minerals together and some concrete admixtures. As a part of a project to investigate optimum mix for the MBC, a series of tests were carried out to study the effect of fly ash content in the MBC mix as a partial replacement of cement. This paper discusses the results from this experimental program and evaluates the optimum fly ash content for the MBC and its associated properties.

Safety management of waterway congestions under dynamic risk conditions—A case study of the Yangtze River

With the continuous increase of traffic volume in recent years, inland waterway transportation suffers more and more from congestion problems, which form a major impediment to its development. Thus, it is of great significance for the stakeholders and decision makers to address these congestion issues properly. Fuzzy Techniques for Order Preference by Similarity to an Ideal Solution (TOPSIS) is widely used for solving Multiple Criteria Decision Making (MCDM) problems with ambiguity. When taking into account fuzzy TOPSIS, decisions are made in a static scenario with fixed weights assigned to the criteria. However, risk conditions usually vary in real-life cases, which will inevitably affect the preference ranking of the alternatives. To make flexible decisions according to the dynamics of congestion risks and to achieve a rational risk analysis for prioritising congestion risk control options (RCOs), the cost-benefit ratio (CBR) is used in this paper to reflect the change of risk conditions. The hybrid of CBR and fuzzy TOPSIS is illustrated by investigating the congestion risks of the Yangtze River. The ranking of RCOs varies depending on the scenarios with different congestion risk conditions. The research findings indicate that some RCOs (e.g. “Channel dredging and maintenance”, and “Prohibition of navigation”) are more cost effective in the situation of a high level of congestion risk, while the other RCOs (e.g. “Loading restriction”, and “Crew management and training”) are more beneficial in a relatively low congestion risk condition. The proposed methods and the evaluation results provide useful insights for effective safety management of the inland waterway congestions under dynamic risk conditions.