| Highway on the national economy and social development is increasingly apparent role in promoting. Highway with large volume, speed, radiation far. high efficiency and advantages, not only led to the improvement of transport structure and transport efficiency, but also to promote the optimization of industrial structure along the line and regional economic development.With economic development, people’s living standards are growing, self-drive cars more and more, in order to meet traffic growth, widening of the existing highway reconstruction is very necessary, especially in countries relative lack of land resources, relative to the road reconstruction, the old road widening to take advantage of the existing roadbed subgrade, shorten the construction period, and accounted for less land for construction. China’s current highway addition to the new line at an unprecedented speed and scale of construction, the renovation and expansion project have gradually become a major highlight of highway construction. Under the highway system for highway expansion decisions limitations and other problems, this paper separately from the main transport means economic and technical characteristics, the regional transportation network planning methods and highway expansion factors presented in three aspects Freeway Rebuilding the further implementation of the integrated transport system principle of coordinated development, mainly in the following three areas of research:First, the main mode of transportation for the current configuration of the status quo can not be reasonably presented in railways, highways, waterways, aviation pipeline and other transport considered together as integrated transport system under highway expansion decisions.Second, for the renovation and expansion of the current highway lack of quantitative decision-making situation, construction funds to build a generalized minimum (ie, LAN system, the total impedance of the smallest, network connectivity maximum) for the upper model of the objective function, travel time to the public at least the lower model objective function, construction funds, service levels, land occupation, status of the environmental impact of the integrated transport system constraints under the freeway expansion decision model.Again, for the LAN node selection the absence of comprehensive standards including the establishment of population, GDP, the proportion of tertiary industry including passenger and freight traffic and passenger turnover of the important evaluation index system, using cluster analysis of regional importance of each node calculation, the area under study area nodes together into the desired number of categories, and according to the importance of the node. carved out an important node level.Finally, for the planning decision problem is huge and very complex systems. this paper uses the bi-level programming model for integrated transport system under the freeway expansion decisions, proven by; bi-level programming model for decision-making with respect to single-level system consider more factors, so that the final decision more realistic, tends to optimum. |
