Moment-rotation characteristics of semi-rigid high tensile bolted connections – II.

It is normal practice for civil engineers designing steel beams and columns to assume that the joints are free to rotate, unless they are especially designed as "fixed" joints, in which case it is assumed rotation is completely prevented. In actual fact, however, the joints are semi-rigid. Some rotation does take place, but this rotation is resisted by the joint and creates bending moment at the ends of the beam. The relationship between the joint rotation and bending moment cannot, as yet, be determined theoretically