ABSTRACT
Dynamic load effects to be considered in bridge design include the following. 1. The maximum vertical loads exerted by a moving vehicle will often exceed
those produced by an equivalent static or slow moving vehicle. The effect has commonly been called impact, with the Impact Factor, I, defined as the ratio of the additional load (dynamic minus static) divided by the equivalent static load. Another term with the same definition is Dynamic Load Allowance. Alternatively, the Dynamic Amplification Factor has been defined as the ratio of maximum dynamic effect to the maximum effect produced by an equivalent static load. Here, the older term, impact, will be retained (but see 4. below).
