Which of the following statements about welded joints is incorrect from a practical fabrication perspective?

Introduction / Context:
Comparing welded and riveted (or bolted) joints is fundamental in steel construction. The modern industry largely favors welding for speed, rigidity, and aesthetics, though execution quality and inspection are crucial.

Given Data / Assumptions:

• Shop and site welding are performed with qualified procedures.
• Riveting is considered a legacy method; bolting is the common alternative today.

Concept / Approach:
Evaluate each statement against standard practice. Welding typically reduces fabrication and erection time for equivalent strength because it avoids hole-making, multiple fasteners, and fit-up complexities associated with riveting.

Step-by-Step Solution:
Rigidity and finish: Welds create continuous connections with good appearance → correct statements.Effective area: In properly designed welds, the member cross-section is not perforated by holes, preserving area → correct.Strength: Full-strength groove welds can match parent metal strength with proper consumables and procedures → broadly correct as a capability statement.Time comparison: Welding usually requires less time than riveting for comparable connections, hence the claim that welding takes more time is incorrect.

Verification / Alternative check:
Industry codes and handbooks (e.g., steel construction manuals) emphasize welding efficiency compared to riveting.

Why Other Options Are Wrong:

• Options a–d reflect accepted advantages/capabilities of welding; they are not incorrect in general practice.

Common Pitfalls:

• Assuming all welds are automatically full-strength; weld design and QA/QC matter.

Final Answer:
Welding takes more time than riveting