Accident Risk Assessment For Various Scenarios Of Maritime And Highway Traffic

Transportation has made possible the fast supply of goods and mobility of people over longer distances.Such large scale transportation has improved the life quality and availability and optimization of resources.Land and sea are considered to be the most dominant players in transportation of goods and people.The volume of traffic in both land and maritime has been ever increasing.However,such high traffic volume and increments are associated with high accident rates.Accidents in maritime and land,specifically highway traffic have been resulting in precious life and huge monetary losses.Every year world has to incur billions of dollars in monetary losses and hundreds of thousands of precious lives with environmental losses above it.These needs to be evaluated and assessed properly in order to reduce the frequency and severity of such accidents.It can be better done in the classification is made on the basis of factors that cause the initiation of such accidents.Although there is no consensus on the statistical distribution of these accidents into categories as per their causation factors.However,various straits of human factors,different environmental and geographic aspects,various ship and vehicular issues and different materials being transported along the onboard equipment are considered to be the most significant contributory factors in the causation of such accidents.Furthermore,human level of related education and skill level,negligence,understanding and abidance of laws,behaviors and fatigue are the most prominent aspects of the human factor.While,visibility,storms,winds,level of light,level of tide and berth and highway location along width and geographic features are considered as the important environmental and geographic straits.Similarly,age,size,tonnage,structure,type of built and performance along availability of various equipment on the vehicle or ship are considered the most critical factors from vehicular or ship perspective.Various studies have been based on the maritime and highway traffic safety pertinent to these factors.However,there are still some scenarios and areas which are never or very less explored and requires further attention for their assessment.This study is aimed at the novel aspects and scenarios in multimodal traffic accident risk assessment.The first emphasis was based on the berthing of hazardous cargo vessels.This topic is of critical prominence and has never been or very less explored before.The methodology adopted for this study is the combination of binary logistics regression & expert judgments for the identification of various influencing factors,and the BN environment for the inference and analysis of these factors.The results indicate that under normal conditions the hazardous cargo vessel risk probability is 3.97% which is lower though,but its risk score indicates that it cannot be ignored and requires attention to be solved.Utilizing the reverse propagation property of BN indicates that for a hazardous cargo accident to occur,human and environment proves to be the most significant contributors.In terms of contribution,environmental factor among all is the most prominent factor,which at its full effect,raises the accident probability to 14.91% with a risk score of 9.17 which is a highly dangerous class II risk requiring immediate solution.This study indicates that the training along the mental & psychological state of ship staff,wind force,water velocity,channel width,berth layout and port location are the most important and significant factors that the authorities need to focus on for the purpose of ensuring the invulnerable berthing of a hazardous cargo vessel.This study has prominent practical viability for port authorities,process safety designers,liner companies,and governments in order to conduct risk management and planning for hazardous cargo vessels.The second scenario selected for this study is the accident risk assessment in Hong Kong waters both in and outside the port environment.The reason to select this scenario is ability of limited resources and one of the highest traffic in the world.Hong Kong’s port is one of the busiest in the world.Such heavy traffic is associated with a high accident rate.The present study uses Bayesian Networks to analyze accident risk in Hong Kong waters using 331 accident reports during the period of 1999-2017.The methodology adopted is comprised of expert judgments for the determination of nodes and states.The calculation of probabilities and conditional probability tables(CPT)were done based solely on the real data in accident reports through parameter estimation.The results indicate that the highest portion of accidents were categorized as “other” with a probability of 51.74%.The majority of such accidents took place in port waters.The second highest category was “collision” with a probability of 22.56%.Both of these accident types were associated with the highest fatality rate-one or two people killed.Poor judgment,negligence and insufficient training were found to be the most influential factors with regard to human actions.The highest rate of injuries was associated with passenger ships.The results offer valuable insights into various accident scenarios which involve setting evidence at different states of consequence and accident type to determine the most prominent contributing factors.A parameter sensitivity analysis was also conducted to recognize the most critical variables.This study should prove useful to decision and policy makers seeking to enhance sustainable safety in maritime traffic operations.The third scenario selected for this study was the effect of earlier mentioned factors on highway traffic.The increase in vehicular traffic have also increased the highway crash frequency with the passage of time.Improvements in highway safety is of vital importance as it could save vast life and monetary losses.The highway crash frequency analysis of major Pakistani highways is a subject less discovered and many important strategic and trade routes are not studied in this regard.This study is aimed to analyze the crash frequency and the prominent factors that cause these crashes on a 302 km section of Indus highway;one of the most important trade routes of the country.Eight years’ data from 2011 till 2018 was arranged into 19 variables where the crash frequency is set as dependent variable,while the eighteen prominent causation factors as independent variables.The tool used for analysis was negative binomial regression being run in the SPSS software.The results indicate that the driver’s behavior,understanding & risk recognition,negligence and law adherence have a significant effect on the crash frequency.Furthermore,highway crash frequency significantly increases with increase in highway segment lengths,number of lanes and lane widths.Similarly,the highway crash frequency significantly enhances when the light,pavement surface and climate condition gets deteriorated.The results of this study are of vital importance to government,transportation companies and general public in order to recognize the most important accident causing factors and devise the transport policies,rules and behaviors accordingly.