Building Stones: Properties

Properties of Building Stones

• Structure refers to the internal arrangement of minerals and bonding of components in stone.
• Texture includes the size, shape, arrangement, and distribution of minerals/crystals within the stone.
• Density is the mass per unit volume of the stone.
• The specific gravity of granite ranges from 2.6 to 2.7.
• Basalt has a Specific Gravity of 2.8 - 3.0
• The specific gravity of sandstone ranges from 2.2 to 2.8.
• Limestone has a specific gravity of 2.3 to 2.7.
• The specific gravity of marble ranges from 2.4 to 2.7.
• Slate has a specific gravity of 2.7 to 2.8.
• The visual appeal, uniformity, and ability to retain polish/durability is regarded as color and appearance.
• Strength determines the stone's ability to withstand applied forces without breaking/deforming.
• Granite exhibits crushing strength of 75 to 127 N/mm^2.
• Basalt has crushing strength of 150 to 185 N/mm^2.
• Sandstone exhibits crushing strength of 64 N/mm^2.
• Limestone's crushing strength is 54 N/mm^2.
• Diorite has crushing strength of 90 to 150 N/mm^2.
• Slate exhibits crushing strength of 75 to 207 N/mm^2.
• Hardness refers to the stones resistance to scratching, abrasion, and indentation.
• Durability is the ability to withstand environmental/mechanical stresses over time without degradation.
• Toughness refers to the ability to absorb energy and resist fracturing under sudden impacts/shocks.
• Porosity measures the proportion of void spaces within the structure relative to the total volume.
• Resistance to fire and weathering determines the ability to withstand high temperatures, weather exposure, and degradation.
• Granite demonstrates a thermal expansion coefficient of 7.5 (10^-6 / °C)
• Basalt demonstrates a thermal expansion coefficient of 6.75 (10^-6 / °C)
• Sandstone demonstrates a thermal expansion coefficient of 11.25 (10^-6 / °C)
• Limestone demonstrates a thermal expansion coefficient of 4.75 (10^-6 / °C)
• Marble demonstrates a thermal expansion coefficient of 5.50 (10^-6 / °C)
• Quartzite demonstrates a thermal expansion coefficient of 11.75 (10^-6 / °C)
• Cost includes the total expense to acquire, process, transport, and use stone on constructions.

Properties of Structural Clays

• Structural clay products possess high compressive strength, enabling support of substantial loads without fracturing.
• Structural clay materials exhibit resistance to wear and chemical attacks, contributing to their longevity in various environmental conditions.
• The thermal mass of structural clay products allows them to absorb and slowly release heat, aiding in temperature regulation within buildings.
• Structural clay products offer design flexibility for architects and builders due to the various colors and textures available.
• Clay-based materials are non-combustible, providing enhanced fire safety for structures.
• Structural clay products reducing sound transmission, improves acoustic comfort in buildings due to the density within the clay.

Properties of Aggregates

• Coarse aggregate (gravel) is a material retained on a sieve with 4.75 mm in openings.
• Fine aggregate's (sand) material passing a sieve with 4.75 mm in openings.
• Coarse aggregate shapes have angular, rounded, flaky, or elongated shape.
• Rough surface aggregate is preferable to smooth aggregate.
• Strength is generally important in high-strength concrete and in the surface course on heavily traveled pavements.
• Specific gravity determines the mass of a material divided by the mass of an equal volume of water.
• Bulk-dry, Bulk-saturated surface-dry, and apparent specific gravity are types of specific gravity.
• The ability of aggregate to withstand weathering defines soundness or durability.
• Aggregate absorption must be evaluated to determine the appropriate amount of water to mix into the concrete.
• Bone dry aggregates contain no moisture.
• Air Dry Condition aggregates may have some moisture but the saturation state is not quantified.
• Saturated Surface-dry aggregates fills the void with moisture but the main surface body is dry.
• Moist Aggregates contains moisture content in excess of saturated surface-dry condition.

Construction Materials

• Construction materials are the physical substances used in building and infrastructure projects.
• Wood is regarded as one of the most ancient and adaptable building materials due to its natural availability, ease of usage, and aesthetic appeal.
• The use of wood or wood-processed goods as the main component of infrastructure and building projects is known as "wood in construction."
• Metals are extensively used in engineering, construction, manufacturing, and technology due to their unique properties.
  • Metals are naturally occurring elements or alloys that exhibit high electrical and thermal conductivity, malleability, ductility, and often a shiny appearance.
• Concrete is one of the most popular building materials in the world because of its strength, adaptability, and durability.
  • It is a composite material composed of cement, water, sand, aggregate (crushed stone or gravel), and occasionally admixtures to improve certain qualities.
• Clay in construction refers to the use of natural clay materials for creating building components and structures.
  • Clay has been used for centuries due to its abundance, versatility, and sustainability
  • It is primarily utilized in its natural state or as a processed material in the form of bricks, tiles, and other products.
• Plastics have become integral to modern construction practices due to their lightweight, durability, and versatility.
  • Usage include synthetic or semi-synthetic materials derived from polymers in various building applications.
• Aggregates are essential for supplying volume, strength, and stability and are granular materials such as sand, gravel, crushed stone, or recycled concrete.
  • Used in the construction industry aggregates are mixed with a binder, like asphalt or cement, to create concrete or asphalt concrete.
• Bricks and stones are among the oldest and most reliable building materials in construction, used for their strength, durability, and aesthetic appeal.
  • Both materials have distinct characteristics that make them suitable for various applications in modern and traditional construction.

Material Testing

• Material Testing is the process of evaluating the physical, mechanical, and chemical properties of materials used in engineering and construction projects.
• Testing construction materials is a critical process in ensuring the quality, safety, and performance of construction projects.
• Material testing helps identify potential weaknesses or defects, ensuring the final structure is durable, safe, and fit for purpose.

Testing Machine

• The Universal Testing Machine (UTM) tests tensile, compressive, and flexural strength of materials like concrete, steel, wood, plastics, and composites.
• The Compression Testing Machine tests the compressive strength of materials like concrete cubes and cylinders, bricks, and stones.
• The Aggregate Testing Machine measures the resistance to crushing, abrasion, wear, and toughness under impact.
• Soil Testing Machines determine soil shear strength, compaction characteristics, and soil stabilibility under conditions.

Significance of Test

• Knowing construction materials and testing extends far beyond selecting the right materials and is essential for safety while ensuring durable, cost-efficient, and sustainable structures.
• Knowledge is essential for ensuring safety, optimizing costs, improving performance, and maintaining quality throughout the construction process.