The steelwork shall be placed in the proper position as per the approved drawing, final riveting or permanent bolting shall be done after proper alignment has been checked and confirmed. During execution, the steelwork shall be securely bolted or otherwise fastened and when necessary temporarily braced to provide for all loads to be carried safely by the structure during erection including those due to erection equipment and its operations. The structure or part of it placed in position shall be secured against overturning or collapse by suitable means. Fabricated members shall be lifted at such points to avoid deformation or excessive stress in members. The work may be erected in suitable units as directed by the engineer. The use of proper equipment such as derricks, lifting tackles, winches, ropes, etc. The contractor, however, shall be fully responsible for the work being carried out in a safe and proper environment without unduly stressing the various members. The method of hoisting and erection proposed to be adopted by the contractor shall be approved by the engineer in advance. The steelwork shall be hoisted and erected carefully in position, without any damage to itself, other structures and equipment, and injury to workmen. Where there is a risk of the nuts being removed or becoming loose due to vibrations or reversal of stresses, these shall be secured from slackening by the use of lock nuts, spring washers, as directed by the engineer.įigure-2: Bolted Connections in Steel Structure Erection of Bolted and Riveted Member. In all cases where the full bearing of the bolt is to be achieved, the bolt must be provided with a washer of sufficient thickness under the nuts to avoid any threaded portion of the bolt within the thickness of the parts bolted together.The threaded portion of each bolt must project at least two threads through the nut.Wherever necessary, washers shall be tapered to give the heads of nuts and bolts a satisfactory bearing.The bolts length shall be such that it must project at least two clear threads beyond the nuts when fixed in position, and these shall fit in the holes without shaking.All bolt heads and nuts shall be hexagonal unless otherwise specified.The nominal diameter of the bolt used in the steel structure shall be the diameter at the shank above the screwed threads, bolts, nuts, and washers shall be thoroughly cleaned and dipped in double-boiled linseed oil, before use.The nominal length of the bolt used in the steel structure shall be the distance from the underside of the head to the further end of the shank.All rivet heads shall be painted with approved steel primer paint within a week of their fixing.įigure-1: Riveted Connection in Steel Structure Process of Bolting in Steel Structure.Where so specified, other tests shall be carried out to ensure the soundness of rivets.
When tested, the rivets shall not give a hollow sound of a jar.0.25 kg shall be used, and both heads of the rivet (especially the machine head) shall be tapped.
For testing rivets, a hammer weighing approx. Caulking and re-cupping shall not be permitted. In cutting out rivets, care shall be taken so as not to injure the assembled members. All loose, burnt, or badly formed rivets with eccentric or deficient heads shall be cut out and replaced. The heads shall be central on shanks and shall grip the assembled members firmly. 
Rivets shall be finished neat, with heads full and of equal size.
The rivets of diameter less than 10 mm may be driven cold. The rivets shall be heated red hot, care being taken to control the temperature of heating so as not to burn the steel. However, when such facilities are not available, hand riveting may be permitted by the engineer. Riveting shall be carried out by using machines of the steady pressure type. For multiple riveted connections, a service bolt shall be provided in every third or fourth hole. The members to be riveted must have all the parts firmly drawn and held together before and during riveting.
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