Research On The Key Techniques Of Highway Capacity Improvement Under The Network Environment

As one of the important infrastructure, highway is a transport mode of a cover wide,mobility, quality of service and high flexible and also the foundation of moderncomprehensive transportation system. In the new journey of basic modernization, needhighway to play the leading role better, to provide a basic support of the industry transition,structure adjustment and development of agglomeration. Especially with the highwayinfrastructure from large-scale construction stage to transfer management stage, as well asagainst this background which highway network management and service levels improve,significantly enhance the ability of innovation of science and technology, highway and naturalenvironment, humanistic environment, the rapid development of regional urban, highway notonly carries road traffic, but also carries the city traffic which put forward higher requirementsof the highway traffic construction, maintenance and management. Therefore, the highway inthe modernization process can look forward better to adapt the new people safe andconvenient travel in comfort, make the intelligent information technology as the guide, tofurther improve the highway traffic industry innovation ability, the new requirements for thedevelopment of highway industry structure adjustment, the new town construction andecological civilization construction. In conclusion, at the same time with the improvement ofhighway network infrastructure network, study related the technology and method to improvethe traffic function of highway network systematically, draw up reasonable and efficienttraffic function promotion plan, will help to improve the road network transport capacity andefficiency, develop its accessibility, safety, efficiency, convergence and comfort of five trafficfunction, to improve the highway network system operation efficiency and service quality.The capacity of highway network was studied in the paper, the traffic function ofhighway was reinterpreted based on the existing theoretical research of highway. Thetransport capacity and efficiency of a given traffic conditions were also described in the paper.Five functional characteristics of safety, efficiency, connectivity and comfort were proposedas the basic characterstics of the traffic function. Therefore, on the basis of the analysis ofhighway traffic function and the connotation&features of highway network traffic capability, the key techniques and methods of enhancing the capacity of the road network under thehighway network environment were in-depth studied. The paper‘s main work includes thefollowing aspects:(1) The traffic flow characteristics of highway network were analyzed in detail. Themicroscopic traffic phenomena of lane changing, speed discrete for vehicle traveling onhighway was researched in the paper. On the basis of a symmetric double-lane cellularautomaton model, the rules of vehicle speed controlling, lane width controlling, Flexiblesecurity lane change spacing, a basic freeway traffic flow cellular automaton model waspresented. By controlling the variable of speed and lane width, the impact on highwaycapacity of the proportion of carts and formulated rules, lane changing conditions wasanalysized, and MATLAB was used in the paper to simulate the highway capacity underdifferent conditions. The results showed that: the model can simulate the temporal and spatialof vehicles on the basic section of highway, Basic freeway capacity by discrete speed, lanewidth and lane change influenced the three common, while showing a different phenomenasuch as traffic congestion, Cellular automata model proposed will improve road capacity,improve resource utilization efficiency of road.(2) On the basic of analysis the factors affecting the highway network capacity,considering the traffic features, the different forms of transportation demand and the bi-levelmathematical programming model, the paper build the general road network capacity model,the limit road network capacity model and the network capacity expansion model. For thethree kinds of road network capacity, the paper design the limit model to solve the networkcapacity based on local linear optimization genetic simulated annealing algorithm, and theexpansion model to solve the network capacity based on the successive average method ofgenetic algorithm model. Shandong provincial highway was as an example to validate themodel. The results show that, the capacity of the road network through the basic model cancalculate the actual speed network capacity Way network; limits of the model can be furthertap the potential of the road network capacity, the capacity of the road network to get moreleverage under; expansion of road network model by determining the bottlenecks and roadreconstruction, further improved network capacity. Road network capacity model under threescenarios for the optimal planning of road network, road network reconstruction and research capacity of the road network provides an effective theory.(3) Based on complex network theory the reliability of highway network capacity can beanalyzed. Firstly, the highway network topology structure is constructed and the statisticalproperties of the highway network topology are analyzed. Secondly, the connectivityreliability, travel time reliability as well as capacity reliability is elucidated. For the capacityreliability we establish a bi-level programming model, in which road segment capacityconstraint is chose as the upper planning and stochastic user equilibrium model as the lowerplanning. A combination of sensitivity analysis and Monte Carlo simulation can solve thebi-level programming model. Finally, the network invulnerability and robustness charactersare studied under the random attack and deliberate attack. Through a case study we canachieve that, the higher level of service, the greater capacity reliability of OD. Also it can befound that when level of service decrease, the reducing speed of capacity reliability increaserapidly. Road network capacity reliability model can give a better reflection of road networkcapacity reliability in different road network capacity requirements. At the same time it cangive a theoretical reference for highway network planning, management, operation, togetherwith network expansion.(4) After analyzing the balance between supply and demand of regional downgradehighway network, on the basis of regional downgrade highway network traffic flowequilibrium theory, this paper proposed key technologies and methods to enhance trafficfunction under highway network environment. By analyzing the vulnerability and robustnessof highway network structure, highway network topologies (regional downgrade highwaynetwork) are established which can reflect the affected area of bottleneck sections andimportant nodes (hubs) of the road. And then, highway mainline control and ramp controlmethods under highway network environment are proposed. Taking the uncertainty whendrivers choose their travel into account, using travel choice behavior under regret theoryperspective, route choice random regret minimization model are established and differences inroute choice results are analyzed comparing with random utility maximization model. Theresults show that, route guidance using fault-tolerant technology is effective dealing with theuncertainty when travelers choose their travel paths under uncertain conditions.