Approximate Calculation of Shear Stiffness of Build-up Arched Pipeline Bridge

Arched pipeline bridge is a practical, medium sized aerial pipeline crossing. Its shear stiffness shall be determined when analysing its structural stability. In turn, the shear displacement and shear stiffness of the truss are needed to calculate shear stiffness of the pipeline bridge. Because the build-up pipe arch is usally flat, and the shear stiffness of the truss recieves no influence from axial curve of the arch, the truss is treated as a straight line. The pipeline bridge is built up with triangle sections, its shear stiffness can be derived from the stress diagram for the truss with triangle section. Similarly, the formulae of shear stiffness for trusses with ladder and diamond sections can also be derived. This method can be used in other shear stiffness calculations for straight line truss.