Vibration Dose Value (VDV) is a metric which evaluates human exposure to incoming vibration levels within a defined time-period. Depending on the orthogonal direction being evaluated, the frequencies that carry significant weight are within 1.5Hz to 8Hz; beyond these frequencies the weighting curves fall almost exponentially. Additionally, a VDV requires to be computed from a time-domain waveform. In the frequency-domain, for stationary signals, the VDV can be approximated through the use of eVDV if a scaling coefficient is known. Whenever proposing a change to a railway configuration alongside residential developments or in supporting the planning application when proposing new residential developments close to a railway system, local authorities tend to require an assessment that establishes the likely vibration impact on building occupants to be evaluated in terms of VDV. Given that in the majority of cases all vibration transfer functions are done in the frequency domain, two issues arise: 1) the challenge in establishing a horizontal eVDV rises significantly, especially because the building related transfer functions (soil to foundation and foundation to floor) for the horizontal direction appear to be limited; 2) the eVDV scaling coefficients for assessing rail-induced vibration are not readily available.
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