Experimental Study on Environmental Vibration Characteristics of a 160 km / h Urban Rail Rapid Transit Underground Line.

With the rapid development of urbanization, the scope of the city is expanding. At present, the design speed of subway is mostly 80 ~ 120 km/ h, which is slightly insufficient for long-distance commuting. In order to better achieve urban integration, higher-speed urban rail transit has emerged and has been put into operation in some cities. In order to grasp the environmental vibration impact of 160 km/ h urban rail rapid transit underground line, this paper carried out a systematic environmental vibration test on the 160 km/ h urban rapid rail transit underground line of a city, including rail, ballast bed and tunnel wall vibration test, as well as ground vibration and indoor secondary structure noise test. The structure shows that when the train speed is 124 to 152 km/ h, the rail vibration is 109. 7 to 111.2 dB, the ballast vibration is 75.6 to 77.4 dB, the tunnel wall vibration is 67.5 to 69.4 dB, and the average speed is 138 km/ h, the tunnel wall vibration is 68.7 dB. After the train vibration is transmitted to the ground, the maximum Z vibration level of the ground vibration is 46.4 to 60.2 dB at the distance of 0 to 40m from the track directly above the tunnel. The ground vibration basically conforms to the attenuation law that decreases with the increase of distance, but the vibration response of the measuring point at 10m from the track is larger than that at 0m. In the case of rubber vibration isolation pad monolithic track bed, the maximum secondary structural noise of the first floor of the building above the tunnel is 32.7 dB(A) and 28.4 dB(A) respectively when the near and far rail trains pass through. [ABSTRACT FROM AUTHOR]