Steel Design Sheet 8
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1) Question.
The order of elongation which a specimen of mild steel undergoes before fracture is
Answer.For mild steel
(i) Proportional limit 190 – 220 N/mm2
(ii) Yield strength 230 – 250 N/mm2
(iii) Ultimate strength 410 – 530 N/mm2
(iv) Fracture strength 250 – 300 N/mm2
(v) Elongation at fracture 23 – 35%
Thus the order of elongation is 10%
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2) Question.
The permissible stress in structural steel under wind and earthquake load condition as per is:800 can be exceeded by about
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3) Question.
The permissible stresses in rivets under wind load condition as per Is:800 can be exceeded by about
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4) Question.
Load on connection is not eccentric for
Answer.In case of double cover butt joint, eccentricity of force does not exist and bending is eliminated whereas it exists in the case of lap joint.
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5) Question.
In a diamond riveting, for a plate of width "b"and rivet diameter"d", the efficiency of the joint is given by
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6) Question.
A weld fillet joint of length L can be subjected to a maximum load of-
(fs= fillet size & pss= permissible shear stress)
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7) Question.
The effective length of fillet weld is
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8) Question.
Which one of the following methods of design is not suitable for structures subjected to impact and fatiuge?
Answer.Plastic or ultimate design considers complete mobilization of strength of material.This method does not take into consideration the effect of impact, fatigue,creep and shrinkage.
Plastic design assumes that the structure can undergo large plastic deformations before failure.
It is suitable for static loads, but not suitable for:
Impact loads (sudden loads)
Fatigue loads (repeated cyclic loads)
Reason: Plastic design relies on redistribution of moments, which is unsafe under dynamic or repeated loading, as it can lead to unexpected failure. -
9) Question.
In a fillet weld the weakest section is the-
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10) Question.
The common assumption that "all rivets share equally a non-eccentric load"is valid at a load
Answer.The assumption that "all rivets share equally a non-eccentric load" is valid at a load equal to the failure load. This is because it is during the failure load, when the material has yielded, that the load is shared equally among the rivets.