Research On Rehandies Problem In Container Terminal

With the continuous deepening of economic globalization and international trade, thedevelopment of port logistics in recent years is very rapid.The container has become the maintransport unit of port logistics.Accompanied by continued growth in container transport, moreand more containers are stacked on the yards, so yard logistics has been taken seriously.Therehandles rate of the yard is an important indicator of the quality of port services, and it notonly affects the level of terminal handling efficiency, but also increases the cost of theterminal operation.At present, the majority of our container terminal faces the problem ofhigh rehandles rate, so it has become a matter of primary importance in the container terminalmanagement.The container terminal system is a typical discrete event system.Firstly, combined with thecontainer terminal processes. This paper uses queuing systems theory to analyze of thequeuing systems and the random variables of the container terminal.We use Flexsimsimulation software to build a container terminal collection and distribution system simulationmodel to describe the operation of the entire container terminal handling system and thevisualization of the action of rehandles, in order to pave the way to study stacking strategies.Then,the rehandles rateof container terminal is studied in the paper.The paper introducesthe classification of rehandles, analyzes the reasons of rehadles from the perspectives of theport yard, shipping companies and their agents, and then put forwards optimization principlesfrom the perspective of process optimizatiom to reduce rehadles, mainly from the perspectiveof the arrangements for entering the container box to reduce rehandles,which leads to thestudy of the stacking strategies of import and export containers.Lastly, stacking strategies for export containers by a random sequence into the portand forimportt containers by a random sequence leaving the port are study by simulation models.Forexport containers,on the analysis of the existing stacking strategies, an improved stackingstrategy with a ground slot as allocation unit is proposed.With simulation modeling andinstance study, the results are shown that the rehandles rate brought by the improved stackingstrategy is much lower than any other existing stacking strategy under the same container yardutilization which is very higher.For import containers,the container stacking problems isdivided into single-ship container stacking problem and multi-ship container stackingproblem.For single ship, appointment stacking strategyis designed and proven to effectivelyhelp to reduce the rehandle rate by single ship simulation model and instance study.For muti-ships,combined with the ship’s entering time and container dwell time and other specificcircumstances, an instance is described in detail the process of using multi-ship simulationmodel to analyze the strategy S1, S2, S3of two-stage stacking strategy,which provide areference to make a decision of choosing stacking strategy using simulation tools.