ABSTRACT
This chapter considers the case typical in engineering practice when an influence line consists of several segments of straight lines. Such lines are called polygonal. The philosophy of structural calculations is based on a probabilistic approach, i.e., while specifying the magnitudes of loads applied to a structure with a probability of about one, there will not appear more dangerous loads during the design life of a structure. The specifications of loads acting on a bridge deck for analysis of bridge framework are standardized by the American Association of State Highway and Transportation Officials in the code referred to as AASHTO LRFD Bridge Design Specifications. The specifications of loads upon a deck for the design of railroad bridges’ frameworks are standardized by American Railway Engineering and Maintenance of Way Association.
