| With the acceleration of urbanization,the phenomenon of “jobs-housing separation” is becoming more and more obvious,which makes a large number of travelers need to commute across regions in the morning peak hours,resulting in serous traffic congestion on highways connecting residential and workplace.Different from the urban road network,traffic congestion can be alleviated by coordinating the choice of travelers’ departure route.The travel demand for cross-regional travel in the morning peak hours is concentrated and the travel route is relatively fixed.It is impossible to alleviate traffic congestion by coordinating the travel paths.Therefore,it is necessary to understand the traveler’s departure time choice behavior.Then,from the time dimension,the traffic flow with concentrated travel time in the morning peak hours can be diverted to achieve the purpose of alleviating traffic congestion.In previous studies,it is generally considered that the main body of travel in the morning peak hours is individual travelers.However,in reality,a family usually own one car due to the high cost of car.Therefore,it is more common for household members to share one car to travel in the morning peak hours.Unlike individual travelers who only need to consider the travel costs associate with themselves,household travelers need to consider the preferences and activities of all household members when making decision.Therefore,this thesis defines a typical household travel,that is,a trip consisting of one parent and one child.On this basis,the equilibrium travel patterns and demand management strategies in the morning peak hours are studied.The main research contents are as follows:1)Research on individual and household travel behavior and staggering policy in the morning peak hours under the parallel bottleneck road networkConsidering the possible differences of individual and household travel paths in the morning peak hours,this thesis studies travel behavior of individuals and households under the parallel bottleneck road network in the morning peak hours.Firstly,according to the characteristics of the parallel bottleneck network,three main factors affecting the user equilibrium are found: the travel demand of two types of travelers,capacity at two bottlenecks and the start time difference between school and work.Secondly,all possible equilibrium travel patterns are inferred under all influencing factor combinations.Then,the relationship between user travel cost and demand ration as well as school-work start time difference is discussed.Finally,this section shows how to adjust the school-work start time difference,that is,staggering policy,to alleviate traffic congestion at the bottleneck.Result shows that adjusting the school-work start time difference provides an option to improve the efficiency and reduce the total travel cost of the system at certain circumstances but it is not effective for all situations to improve system efficiency.2)Research on individual and household travel behavior and staggering policy considering school bus in the morning peak hoursWith the continuous application of school buses in major cities,it has changed the single way of household travel in the past,that is,parents drive their children to school and then go to work.Based on this,this section studies the travel decision-making behaviors of individuals and households under the influence of school buses in the morning peak hours.Firstly,under the dual-traffic travel mode of school bus and car,the travelers are divided into three categories:individual travelers,household travelers who use school buses and household travelers who do not use school buses.What’s more the travel cost of three types of travelers are constructed respectively.Secondly,all possible equilibrium travel patterns are derived based on the travel cost function and bottleneck model,and the departure time choice behavior of individual travelers and the departure time choice behavior and travel mode choice behavior of household travelers are analyzed.Thirdly,the effects of school bus fees and the school-work start time difference on the travel cost of users are analyzed respectively based on the equilibrium travel patterns.Finally,it discusses how to minimize the total travel cost of the transportation system by setting the optimal time difference between school and work,so as to improve the operation efficiency of the transportation system.Result shows that the optimal school-work start time difference setting is not unique,and its value is different due to the influence of school bus fees.3)Research on the household travel behavior and congestion pricing in the morning peak hours based on activity approachIn addition to being influenced by traffic congestion at bottlenecks,travelers’ departure time choice behavior in the morning peak hours may also be influenced by activity utility,such as at home,school and workplace.Based on this,this section analyzes the impact of activity utility on the departure time decisions of household travelers in the morning peak hours from the perspective of activity utility.Firstly,this section constructs the net utility function of household travels by taking into account the disutility of household travel and the positive utility of household members’ activities at home,school and work.Secondly,based on the bottleneck model and the net utility function,a household travel equilibrium model in the morning peak hours is constructed to analyze the departure time choice behavior of household travelers.Thirdly,a step toll is proposed to manage traffic congestion when the staggering policy is ineffective.Finally,the influence of the desired arrival time difference between work and school on the total utility of system,the toll level and the toll time period is discussed.Result shows that the step toll model can be further optimized by adjusting the school-work start time difference,thereby improving the total utility of the system. |
