Pick up the correct statement from the following:
🧱 Matching Stone Properties to Applications
The principle of "form follows function" is very true in construction. The inherent properties of a building material, like stone, dictate its best use. This question tests the understanding of this principle.
🔬 Detailed Analysis of the Statements
Let's examine why each statement is a correct application of material science.
A. Soft stones are required for carving
This statement is correct. Carving involves creating intricate details, ornamental work, and sculptures. A stone must be soft enough to be worked with tools like chisels without excessive effort or cost. Hard stones like granite would be extremely difficult and time-consuming to carve in detail.
- Property: Low Hardness / Good Workability.
- Examples: Soapstone, certain types of Sandstone, and Limestone are often used for carving and ornamental work.
B. Light stones are required for arches
This statement is correct. Arches, vaults, and domes are self-supporting structures, but their own weight (dead load) is a major force they must carry. Using a lighter stone reduces this dead load, which in turn reduces the stress on the supporting abutments and foundations. This makes the overall structure more efficient and stable.
- Property: Low Specific Gravity / Low Density.
- Examples: Light-weight sandstones or tuffs are preferred for these types of structures.
C. Hard stones are required to stand high pressure
This statement is correct. Structural elements that are subjected to high compressive forces, such as foundations, columns, piers, and pavement blocks, must be made from stone with high crushing strength. A hard, dense stone will not crush or fail under heavy loads.
- Property: High Hardness / High Compressive Strength.
- Examples: Granite, Basalt, and Quartzite are known for their exceptional strength and are used for heavy structural work.
D. All the above
This is the best answer. Since each of the individual statements correctly matches a specific stone property to its appropriate application, the most comprehensive and accurate answer is "All the above".
📊 Summary: Property vs. Application
| Required Property | Justification | Ideal Application | Example Stones |
|---|---|---|---|
| Softness / Workability | Easy to cut, shape, and carve. | Carving, ornamental work, sculpture. | Soapstone, Sandstone |
| Light Weight | Reduces the dead load on the structure. | Arches, domes, vaults. | Light Sandstone, Tuff |
| Hardness / Strength | Resists crushing under high pressure. | Foundations, columns, pavements. | Granite, Basalt |
💡 Study Tips
- Think like an Engineer: For every application, ask "What is the main challenge?" For carving, the challenge is shaping it. For arches, it's weight. For foundations, it's pressure.
- Match the Property to the Challenge: Softness solves the shaping challenge. Lightness solves the weight challenge. Hardness solves the pressure challenge.
- General Rule for "All of the above": In questions about properties or requirements, if each individual option seems logical and correct on its own, "All of the above" is a very strong candidate for the right answer.