DESIGN OF STEEL STRUCTURES (General Technical Specification)

General

This specification shall apply to structural steel work. For technological structures, additional stipulations shall be considered as per technical requirements.

Design considerations

General

Structures shall be designed such that they are economical and safe and meet the functional and service requirement of the technological process for which they are designed. The architectural planning of the building shall be based on technological requirements.

The structures shall be designed conforming to the relevant safety regulations, Factory Acts, Electricity Rules and stipulations of statutory bodies as applicable to the project.

Natural ventilation shall be provided ensuring that it does not permit rain water entry into the building. Scope of natural lighting shall be used to the maximum possible extent.

Mild steel gutters and down-pipes with gutter outlets having grating cover shall be provided to carry rain water from roofs of buildings to the drainage system at ground level. All gutters shall be designed as walkable with 600 mm sole width.

Adequate facilities in the form of monorails, hoists, platforms etc. shall be provided to facilitate repair and maintenance of overhead cranes, equipment, etc. Access to these platforms shall be provided by stairs / ladders from the nearest accessible floor or platform.

Access to all floors, gangways and landings shall be by staircases. Access to platforms and landing of secondary importance or where such access is used only rarely, shall be by vertical ladders with safety hoops.

Roofs with access shall be provided with safety handrails along the periphery of the roof.

Edges of floors, gangways, stairs and landings shall be provided with safety hand railings.

At gable ends of buildings, platforms shall be provided connecting the walkways at crane gantry level.

Floors, gangways and landings shall be covered as follows:

a) Gangways and landings shall have chequered plate with a minimum thickness of 6mm o/p suitably stiffened to meet design load requirements.

b) Floors and operating platforms other than the above shall have chequered plate flooring or hot dip galvanised open gratings, or RCC slab resting on steel structural framework, to suit the technological requirements.

Protective metal heat shields shall be provided for steel structures exposed to continuous heat radiation of temperature exceeding 150 °C and also where hot metal splashing on structures is likely to occur.

All buildings and their foundations shall be designed so that it shall be possible to extend them in the longitudinal direction at a later date without further strengthening of gable structures. Provision for transverse extension, if any, shall also be made at the initial stage.

Sheeting on sides and gables shall generally terminate 3.0 m above ground floor level unless required to be otherwise. Sides below this level shall be generally screened by brick walls allowing sufficient air inlet to achieve natural ventilation, unless otherwise required from technological / ventilation requirements.

Connection by permanent bolts to structural elements subject to vibration shall be provided with lock nuts.

For Analysis/ design of steel structural frame work STAAD PRO software shall be used.