Building Construction & Materials: Foundations & Materials

Vocabulary flashcards covering the definitions, functions, types, and materials of building foundations, as well as causes of foundation failure.

Foundation

The lowest part of the building structure that supports the building and transmits the load of the structure to the soil or subsoil.

Site Investigation

The first task to be completed before the construction of a foundation starts.

Bearing Capacity

The safe load per unit area which the ground can carry, representing the maximum average contact pressure between the foundation and the subsoil.

Topsoil

The layer of soil about $300\,mm$ deep from the ground level surface.

Typical Bearing Capacity of Rock (Granite)

Range between $600\,kN/m^2$ and $10,000\,kN/m^2$.

Shallow Foundation

Sometimes called 'spread footing,' these rest on stratum with adequate bearing capacity and are laid less than $3\,m$ below ground level.

Pad Foundation

Also known as an isolated foundation, it is used to support individual point loads such as structural columns and is suitable on high bearing capacity subsoil.

Reinforcement bars for Pad Foundation

Steel bars typically $12\,mm$ in diameter used to strengthen the base.

Concrete

A mixture of cement, fine aggregate, coarse aggregate, and water where proportions control the strength and quality.

Portland Cement

A cement made from limestone and clay, generally produced by a wet process.

Fine Aggregate

Aggregate materials, such as sand, that pass through a standard $5\,mm$ sieve.

Coarse Aggregate

Aggregate materials, such as gravel or crushed stone, that are retained on a standard $5\,mm$ sieve.

Concrete Grade

The concrete compression resistance measured in Newtons per square millimeter ($N/mm^2$) after 28 days.

Grade M15

An ordinary concrete mix with a ratio of 1:2:4 (1 part cement, 2 parts fine aggregate, 4 parts coarse aggregate) used for solid ground floors.

Ready-mix Concrete

Concrete manufactured in a factory or batching plant according to a set recipe and delivered to a site by lorry mounted in-transit mixers.

Raft Foundation

A foundation that spreads the load over the entire area of the structure, often used on soft or loose soils with low bearing capacity.

Cellular Raft Foundation

A foundation where internal walls are used to spread the load over the raft and divide the void into cells.

Damp Proof Membrane (DPM)

A sheet installed during foundation construction (such as Beam & Slab Raft) to prevent moisture from rising through the structure.

Strip Foundation

A foundation used to support a line of loads, such as a load-bearing wall, suitable on high bearing capacity subsoil.

Trench-fill Foundation

Similar to strip foundations but dug deeper and thicker (not less than $500\,mm$), practical for high water tables or heavy clay soils.

Deep Foundation

A form of foundation, such as pile foundation, used to transfer loads to a firm soil stratum with sufficient load-taking capacity at significant depths.

Bakau Piles

Timber (mangrove) piles widely used in Peninsular Malaysia known for their high density, strength, and low cost.

Displacement Piles

Piles that cause the soil to be moved radially and vertically as the pile shaft is driven or jacked into the ground.

Skin Friction Support

A support method where the load is carried by the frictional resistance between the contact surface of the pile and the surrounding soil.

End-Bearing Support

A support method where the load is carried by resting the pile on a firm stratum such as bedrock.

Silent Piler

A hydraulic machine for vibration-free installation or extraction of sheet piles by gripping previously driven piles to provide reaction force.

Caisson

A water-tight retaining structure used to allow construction work to be undertaken under dry conditions below the water table.

Transpiration

A cause of foundation failure where tree roots dehydrate the soil beneath a home, causing soil shrinkage and settlement.

Evaporation

A cause of foundation failure where hot and dry conditions cause soil to pull away from the foundation, leading to moisture imbalance and cracks.