A Survey on Formation Multi Unequal Span Masonry Bridges with Curve Shaped Deck: A Case Study on Khan Bridge in Iran

Abstract

Masonry arch bridges with unequal spans are outstanding kinds of masonry bridges which are widespread in historic countries spatially in Iran. The differences in dimension of arches which mostly lead to formation of curve shaped decks in such bridges, brings a particular architecture for masonry arch bridge. However the elements which bring different lengths and heights for spans have not yet been studied. In this research by geometrical and structural survey on Khan Bridge, a kind of multi unequal span bridge in south west of Iran, it is demonstrated that especial conditions of the case lead to formation of its architecture. It is illustrated that shape of river bed, hydraulic and geotectonic factors and structural stability, are of paramount importance in terms of featuring the architecture of multi unequal span bridges with curve shaped deck.