Riveted connections (IS practice) – permissible shear: According to Indian Standards for structural steelwork, what is the recommended working shear stress on the gross (shank) area of a rivet?

Introduction / Context:
In steel design using riveted connections (still encountered in assessment of existing bridges and buildings), permissible or working stresses are used to size rivets and to verify legacy details. One frequently tested value is the allowable shear stress on the gross shank area of a rivet as per traditional Indian Standards practice.

Given Data / Assumptions:

• Structural steel rivets in shear.
• Working stress (allowable stress) design context.
• Shear is evaluated on the gross shank area (not reduced for threads since rivets are headed shanks).

Concept / Approach:
Codes specify different allowable stresses for rivets in shear and in bearing. Typical legacy values used in exam problems are about 1025 kg/cm2 for rivet shear (on gross area) and a much higher value for bearing (crushing) on connected plates or rivets. Recognizing which value corresponds to which limit state is essential to choosing the correct option.

Step-by-Step Solution:
Identify the limit state asked: shear on gross rivet area.Recall standard IS-era values: shear allowance ≈ 1025 kg/cm2 (shop-riveted), distinctly lower than bearing allowance.Select the option that matches this commonly adopted working shear stress: 1025 kg/cm2.

Verification / Alternative check:
Many solved examples in classic Indian steel design texts adopt about 1000–1025 kg/cm2 for rivet shear, while bearing stresses are commonly taken around 2360 kg/cm2. The presence of both numbers among the options is a cue to avoid mixing up shear and bearing values.

Why Other Options Are Wrong:

• 785 kg/cm2: too low for the standard working shear value; may apply to special cases or field constraints.
• 2360 kg/cm2: this aligns with bearing (crushing) allowance, not shear.
• None of these: incorrect because 1025 kg/cm2 is the expected answer in this setting.

Common Pitfalls:

• Confusing allowable shear with allowable bearing.
• Using bolt thread-area logic for rivets (rivets are not threaded in the shear plane).

Final Answer:
1025 kg/cm2