How to construct curved bridge and skew bridge?

As constructing curved bridge, adjust intersection angle between front support leg and middle support leg according to actual condition of curve radius, and adjust the position of front and middle support legs at both sides along main girder to meet the construction of curved bridge.

As constructing skew bridge, keep front and middle support legs in a level according to the angle of skew bridge; just adjust the position of front and middle support legs at both sides along the main girder to meet the construction of skew bridge.