Study On Green Construction Measures And Effect Evaluation Of Railway Tunnels For Cold And Arid Areas In Northwest China

The railway construction in northwest China has been developed rapidly in recent years,which has brought great benefits to the people's production and life in northwest China.However,with the expansion of the scale of railway construction,the impact of railway construction,especially large-scale construction behavior such as railway tunnels,on the ecological environment and natural resources along the line and the problems of consumption are becoming more and more prominent.In northwest China,the climate is cold and arid,and the ecological environment is very fragile.The construction of railway tunnels in this area will highlight the problems of resource conservation and environmental protection.Therefore,it is of great significance to study the most reasonable,economical and suitable green construction measures in technology under the condition of ensuring construction quality and construction safety to achieve the goal of project quality and safety while minimizing the impact of construction behavior on the ecological environment and saving resources,and to protect the ecological environment in northwest cold and drought areas and to promote the green construction of railways.Based on the analysis of the regional characteristics of northwest cold and drought areas and the characteristics of railway tunnel construction,this paper combines the concept of sustainable development in China and the research results of tunnel construction,environmental impact and environmental protection at home and abroad,refers to the railway quota in China and the relevant standards and norms at home and abroad,and comparatively analyses the existing green tunnel construction measures by the method of technical and economic analysis.Through comparative analysis,a comprehensive evaluation model of tunnel green construction effect is constructed,which is verified by the actual railway tunnel project.Firstly,through reading the literature of green construction and railway tunnel construction at home and abroad,this paper summarizes the relevant research results,defines the connotation of green construction and the concept of green construction of railway tunnel,and chooses the appropriate technical and economic analysis method and comprehensive evaluation model for the research content.Secondly,through the analysis of the specific regional characteristics of northwest cold and drought areas,combined with the construction process and characteristics of railway tunnels,based on the process decomposition,the main factors affecting the green construction of tunnels are found to be debris disposal,waste water treatment,material loss,energy-saving discharge,and the corresponding green construction methods of railway tunnels are put forward in combination with the characteristics of ecological fragility and main influencing factors in northwest China.Thirdly,based on the theory of value engineering,this paper uses the method of techno-economic analysis while taking Dayangshan Tunnel on Lanzhou-Xinhua Second Line,Yantatai Tunnel,Section XGZHQ5-2 for Guanjiao Tunnel of Qinghai-Tibet Railway and Guojiazhen Tunnel of Baolan Passenger Special Station as the basic data sources,compares and analyses the benefits and implementation costs of various green construction measures for railway tunnels.Nine green construction measures for railway tunnels in northwest cold and drought areas were selected according to the results of benefit,cost calculation and measure value coefficient.Finally,according to the relevant standards of green railway and green construction and the analysis of green construction measures for railway tunnels,the evaluation index system of green construction measures for railway tunnels in northwest cold and drought areas is constructed,and the evaluation model based on set pair analysis is established.The actual railway tunnel project is taken as an example to verify the evaluation result.The evaluation results show that the effect of the measures of the Section XGZHQ5-2 for Guanjiao Tunnel is " preferably ",that of the Dayangshan Tunnel is "general" and that of the Yantatai Tunnel is "qualified".