Column Base Restraint Effect for a Steel Portal Frame

Self-certification of structural design Under the heading ‘Serving and protecting the profession’, our column for 7 December last included an invitation from Allan Lowe for information on the progression, since its introduction in Scotland, of ‘self-certification’. Mr A. C. Aiken, of Glasgow, ofsers his experience: Mr Lowe asks for feedback on self-certification of structural design in Scotland. Well, when the hated Forms 4A and 4B were first introduced a year ago, there were screams of protest. Since then there has been almost complete silence on the subject. Verulam

The influence of compressive axial load on the shear capacity of reinforced concrete elements is investigated, using results from tests on 15 external reinforced concrete beam-column connection specimens. Shear stresses in the connection zones of these specimens are compared with values predicted by the design equations in BS 8110 and observations made concerning the applicability of these equations. The revised eqns. (6a) and (6b) in BS 8110 are presented and recommendations made for assessing shear stresses at initial joint cracking and specimen failure. Bearing stresses within bends in the reinforcement in the connection zones are also evaluated and compared with the recommendations of BS 811O.

Mr J. E. A. Tapsell (M), (Tapsell Wade & Partners) This is a very tantalising building, still 'shrouded in mystery'. The paper refers, in very general terms, to the steel structure, and I hope that the authors will be able to give more details about the actual steel frame. I am interested in the combined steel and concrete floor, the connections used between the floor beams and the steel columns, the stability bracing in the lift and stair towers, and a more detailed plan (if possible) of the stair and lift areas. I should like to know how the steel stanchions and bracing were clad.