Designation of rolled steel beams in India Rolled steel beams are designated by the Indian Standard series together with which two key parameters?
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AWeight per metre and depth of its section
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BDepth of section and weight per metre
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CWidth of flange and weight per metre
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DWeight per metre and flange width
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EDepth of section and web thickness
Answer
Correct Answer: Depth of section and weight per metre
Explanation
Introduction / Context:Section designation standards enable quick communication of a member’s size and mass. In Indian practice, rolled beams (e.g., ISMB, ISUB, ISHB) include both the depth and the linear mass so that designers can identify geometry and weight during selection.
Given Data / Assumptions:
- Indian Standard section series (e.g., ISMB) is used.
- Typical catalogue entry: ISMB 300 @ 44.2 kg/m.
- We need the two parameters stated after the series name.
Concept / Approach:The conventional order is depth (in mm) followed by weight per metre (kg/m). This succinctly conveys size and self-weight implications without listing the entire sectional table every time.
Step-by-Step Solution:
Recall common notation: “ISMB 300 @ 44.2 kg/m”.Identify parameters: depth = 300 mm; weight per metre = 44.2 kg/m.Thus, the designation uses depth of section and weight per metre.Verification / Alternative check:Standard steel tables and supplier catalogues follow this same practice.
Why Other Options Are Wrong:Flange width/web thickness are not part of the short designation; the order “weight then depth” is not the conventional format.
Common Pitfalls:Confusing designation with full sectional properties (e.g., Ix, Zx, r). Those are referenced separately in design checks.
Final Answer:Depth of section and weight per metre