ABSTRACT
A structure's main function is to transfer loads, the sources of loads can be divided into natural, useful and accidental loads. Natural loads occur due to the existence of the structure in the world; useful loads are ones that occur from the purpose of the structure; and accidental loads occur from the misuse of the structure. Useful loads happen because the building and hence the structure have been constructed for a useful purpose. The amount of useful load can be altered by how many people are 'allowed' on the bridge at any one time; and whether people are allowed to take their pet elephants on the bridge. To understand how loads are transferred through complex structures the concept of load path is used. The load path joins the load from its point of application to the final support point. The identification of vertical load paths for most buildings is relatively straightforward.
