16.The effective length of a battened strut effectively held in position at both ends but not restrained in direction is taken as

17.Minimum spacing of vertical stiffeners is limited to

18.Intermediate vertical stiffeners in a plate girder need be provided if the depth of web exceeds

19.Battening is preferable when the i) column carries axial load only ii) space between the two main components is not very large iii) column is eccentrically loaded The correct answer is

20.Angle of inclination of the lacing bar with the longitudinal axis of the column should preferably be between