Subway Vibration And Electromagnetic Environmental Effects And Control Measures

Subway, as a kind of underground city transportation, its advantages have been admitted by the society for its large transportation volume, safety and reliability, fast and punctuality, convenient and comfortable, no air pollution, and promotion of economic development. But the subway operation also causes vibration and electromagnetic pollution. Along with the mass construction of the subway, the negative impact of the urban environment has caught widespread attention and should not be ignored.This paper based on the summary and analysis of the subway vibration, electromagnetic environmental impact prediction and prevention, with the combination of an example of a certain city subway construction, predicting and evaluating the environmental influence of subway vibration and electromagnetic. It also proposes some prevention measures on the vibration and electromagnetic environmental influence. This paper achieved the following conclusions:1.The main impact of city subway on the environment is its vibration and electromagnetic environment pollution. The subway line selection and site selection should try to avoid environmental sensitive spots like the residential areas, high-rise buildings, hospitals, schools and historic buildings as well as to control the vibration and electromagnetic pollution of the environment.2. Subway vibration quantitative forecast result shows that under the prediction conditions, along the line of Subway A, the prediction of ten sensitive spots VLzl0ranges from45.7-62.8dB which all meet the relevant standards. For Ⅱ class buildings, the rail lay depth of15m, section form is rectangular cross section, a distance over17.4m of orbit can meet the relevant standards; Sections form for circular section, a distance over6.7m of orbit can meet the relevant standards.3.Subway vibration velocity analogy analysis shows:the ancient city wall I, the ancient building and the ancient city Ⅱ shall take avoidance measures in which the rail lay depth of20m, a distance over17.4m of orbit can meet the relevant standards; Measures of antivibration should be taken for ancient towers in which orbit buried for20m, a distance over5m of orbit can meet the relevant standards.4.Subway electromagnetic analogy analysis shows:the electromagnetic wave frequency of the running subway will not affect the effect of television of the residents along the subway A line;110kV substation outdoor and high voltage cable power frequency electric field and magnetic induction intensity are less than the limit stipulated standards. The electromagnetic radiation will do no harm to human health.5.City subway vibration environmental influence put forward main vibration measures like reasonable planning, optimization design, source control(cars, track structure and the management maintenance), reduce at the communication process(vibration isolation ditch, fence piles, damping wall, buffer, and vibration isolation wall) and acceptor(sensitive target protection) etc. The main electromagnetic protection measures are substation line selection and design, electromagnetic shielding, transmission line(try to adopt underground, on the ground should be shielded) etc.