EFFECTIVE LENGTH OF COMPRESSION MEMBERS. IN: BRIDGE ENGINEERING: SUBSTRUCTURE DESIGN

The concept of effective length factor or K factor plays an important role in compression member design. Physically the K factor, when multiplied by actual length of the end-restrained column, gives the length of an equivalent pin-ended column whose buckling load is the same as that of the end restrained column. Practically, design specifications provide the resistance equations for pin-ended columns, while the resistance of framed columns can be estimated through the K factor to the pin-ended column strength equations. This paper presents the state of the art engineering practice of the effective length factor for the design of columns in bridge structures.