I'm interested in some theory Eurocode 1: Actions on structures - Part 2: Traffic loads on bridges. How were the limits chosen (e.g. maximum deck acceleration = 3.50 m/s2)? Why is the lower limit of $n_0$ governed by dynamic impact criteria and given by the following?
$$n_0 = \begin{cases} 80/L, &4m<L<20m \\[2ex] 23,58L^{-0,592}, &20m<L<100m \end{cases}$$