Effects of Drifting on Snow Loads on Large Roofs

In areas that experience significant snow fall, snow loads typically produce the governing environmental load cases for a large span roof. Therefore for large span roofs there are considerable benefits to be had from understanding the drifting processes and being able to make quantitative predictions as to their effects on the snow loads. This paper describes some of the more important drifting processes that occur and shows how special purpose scale model studies and computer simulations can assist the designer in defining loads for large span , complex shaped structures.