Difficulty: Medium
Correct Answer: All of the above
Explanation:
Introduction / Context:Brick quality is often summarized by compressive (crushing), tensile, and shear strengths. While compressive strength is the principal criterion, awareness of typical ranges for other strengths helps in design checks and material selection. This question tests recognition of commonly cited average values for hand-moulded bricks in older unit systems.
Given Data / Assumptions:
Concept / Approach:Compressive strength of conventional bricks far exceeds their tensile and shear strengths. The listed values represent typical magnitudes referenced in traditional texts, acknowledging variability with raw material, firing, and porosity.
Step-by-Step Solution:
1) Crushing (compressive) strength of ~6000 t/m² corresponds to expected ranges for ordinary quality bricks in legacy units.2) Tensile strength is a small fraction of compressive strength; ~200 t/m² as an order-of-magnitude average is reasonable.3) Shearing strength typically lies between tensile and compressive values; ~600 t/m² is a plausible average figure.4) Therefore, the grouped “All of the above” best represents the stated averages together.Verification / Alternative check:Cross-check with standard building materials references that present approximate values and stress the dominance of compressive over tensile capacity in masonry units.
Why Other Options Are Wrong:Each single value captures only part of the picture; the comprehensive and correct set is “All of the above.”
Common Pitfalls:Comparing these legacy units directly with modern N/mm² without conversion; ignoring wide variability across classes and manufacturing quality.
Final Answer:All of the above
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