Vibration detection for rail transit

With the development of urban subway and other rail transit, the vibration and noise issues of urban rail transit are increasingly attracting people's attention. The testing of indoor vibration and noise generated by urban rail transit is the primary task for effectively evaluating the impact of rail transit vibration and noise on people. During the operation of rail transit, its vibration and noise are mainly transmitted through the structure. Therefore, testing the vibration and noise of rail transit mainly involves testing the vibration and structural noise generated by rail transit operation

Currently, the main standards for testing vibration and structural noise generated by rail transit operation are as follows:

GB/T 50355-2018 Standard for Indoor Vibration Limits and Measurement Methods of Residential Buildings

HJ 793-2016 Structural Noise Detection Method for Urban Rail Transit (Underground Section)

JGJ/T 170-2009 Standard for Limits and Measurement Methods of Building Vibration and Secondary Radiation Noise Caused by Urban Rail Transit

DB31/T470-2009&Nbsp; Limits and Measurement Methods for Indoor Vibration and Structural Noise in Residential Buildings Caused by Train Operation in Urban Rail Transit (Underground Section)

Among them, GB/T 50355-2018 is a national standard, so its applicability is the widest and most effective; HJ 793-2016 is a standard of the Ministry of Environmental Protection, which only provides testing methods for structural noise and does not provide evaluation standards; JGJ/T 170-2009 is the industry standard of the Ministry of Housing and Urban Rural Development; DB 31/T470-2009 is a local standard in Shanghai and is generally only valid in Shanghai

In terms of vibration testing methods, GB/T 50355-2018, JGJ/T 170-2009, and DB31/T470-2009 are all quite similar, measuring the maximum acceleration level of at least 5 trains passing up and down, and then evaluating them. However, GB/T 50355-2018 not only provides the total vibration limit values for vibration acceleration, but also provides vibration limits for 20 1/3 octave bands in the range of 1-80Hz; JGJ/T 170-2009 provides vibration limits for 18 1/3 octaves in the range of 4-200Hz; However, DB 31/T470-2009 only provides overall vibration limits, but does not specify the weighting method used for vibration. Based on the standards and instrument requirements cited in this standard, it can be inferred that the frequency weighting is environmental vibration weighting

From the vibration limit values of the three standards, due to the different evaluation frequency bands and weighting methods of the three standards, it is not possible to fully compare the evaluation values of each standard. However, due to GB/T 50355-2018 providing vibration limits for 20 1/3 octave bands in the range of 1-80Hz, JGJ/T 170-2009 provides vibration limits for 18 1/3 octave bands in the range of 4-200Hz; Both standards provide vibration limits in the 4-80Hz frequency band. Therefore, within the range of 4-80Hz, the two standard evaluation frequency bands overlap; Overall, within these two overlapping frequency bands, the first level limit for bedrooms given in GB/T 50355-2018 is equivalent to the second level sound environment limit given in JGJ/T 170-2009. Considering that most residential buildings have Class 2 or Class 1 acoustic environments, the requirements given in JGJ/T 170-2009 are generally higher than those in GB/T 50355-2018