The Basic Civil Engineering Materials: What You Need To Know

On: September 30, 2025

Basic Civil Engineering Materials include stones, bricks, cement, lime, sand, steel, and timber. These are the Engineering materials used for civil engineering constructions worldwide.

In this engineering post, the types, properties, tests and uses of these engineering materials are explained.

Also Read: Engineering Disciplines: A Complete Guide

Stones

Stone is a ‘naturally available building material’ which has been used from the early age of civilisation.

It is available in the form of rocks, which are cut to the required size and shape and used as building blocks.

Stones have been used to construct small residential buildings and large palaces all over the world.

Types of Stones as Engineering Materials

Stones used as civil engineering materials may be classified into the following:

Geological
Physical
Chemical

Geological Classification

This classification is based on their origin of formation. Stones are classified into three main groups:

Igneous: These rocks are formed by the cooling and solidification of the rock masses from their molten magmatic condition of the material of the earth. Generally, igneous rocks are strong and durable. Granite, trap and basalt are the rocks that belong to this category. Granites are formed by the slow cooling of the lava under a thick cover on the top. Hence, they have a crystalline surface. The cooling of lava at the top surface results in a non-crystalline and glassy texture. Trap and basalt belong to this category.
Sedimentary: Due to the weathering action of water, wind and frost, existing rocks disintegrate. The disintegrated material is carried by wind and water; the water being the most powerful medium. Flowing water deposits its suspended materials at points of obstacles to its flow. These deposited layers of materials get consolidated under pressure and by heat. Chemical agents also contribute to the cementing of the deposits. The rocks thus formed are more uniform, fine-grained and compact in nature. They represent a bedded or stratified structure in general. Sandstones and limestones belong to this class of rock.
Metamorphic rocks: Previously formed igneous and sedimentary rocks change due to the metamorphic action of pressure and internal heat. For example, due to metamorphic action, granite becomes gneiss, trap and basalt change to schist and laterite, limestone changes to marble, sandstone becomes quartzite, and mudstone becomes slate.

Physical Classification

Based on the structure, the rocks may be classified as:

Stratified Rocks: These rocks have a layered structure. They possess planes of stratification or cleavage. They can be easily split along these planes. Sandstones, Limestones, slate, etc., are examples of this class of stones.
Unstratified Rocks: These rocks are not stratified. They possess crystalline and compact grains. They cannot be split into thin slabs. Granite, trap, marble, etc., are examples of this type of rock.
Foliated Rocks: These rocks tend to split along a definite direction only. The directions need not be parallel to each other, as in the case of stratified rocks.

Chemical Classification

Based on their chemical composition, engineers prefer to classify rocks as:

Silicious rocks: The main content of these rocks is silica. They are hard and durable. Examples of such rocks are granite, trap, and sandstone.
Argillaceous rocks: The main constituent of these rocks is argill, i.e., clay. These stones are hard and durable, but they are brittle. They cannot withstand shock. Slates and laterites are examples of this type of rock.
Calcareous rocks: The main constituent of these rocks is calcium carbonate. Limestone is a calcareous rock of sedimentary origin, while marble is a calcareous rock of metamorphic origin.

Properties of Stones as Engineering Materials

The following properties of the stones should be looked into before selecting them for any engineering works:

Structure: The structure of the stone may be stratified (layered) or unstratified. Structured stones should be easily dressed and suitable for superstructure. Unstratified stone is hard and difficult to dress. They are preferred for the foundation works.
Texture: Fine-grained stones with homogeneous distribution look attractive, and hence they are used for carving. Such stones are usually strong and durable.
Density: Denser stones are stronger. Lightweight stones are weak. Hence, stones with a specific gravity of less than 2.4 are considered unsuitable for construction works.
Appearance: A stone with uniform and attractive colour is durable if the grains are compact. Marble and granite get a very good appearance when polished. Hence, they are used for face work in buildings.
Strength: Strength is an important property to be looked into before selecting stone as a building block.
Hardness: It is an important property to be considered when stone is used for flooring and pavement structures.
Porosity and Absorption: All stones have pores and hence absorb water. The reaction of water with the material of the stone causes disintegration.
Weathering: Rain and wind cause loss of the good appearance of stones. Hence, stones with good weather resistance should be used for face work.
Toughness: The resistance to impact is called toughness. It is determined by an impact test.
Resistance to Fire: Sandstones resist fire better. Argillaceous materials, though poor in strength, are good at resisting fire.
Ease in Dressing: The Cost of dressing contributes to the cost of stone masonry to a great extent. Dressing is easy in stones with lesser strength. Hence, an engineer should look into sufficient strength rather than high strength while selecting stones for building works.

Requirements of Good Building Stones as Engineering Materials

The following are the requirements of good building stones:

Strength: The stone should be able to withstand the load applied to it.
Durability: Stones selected should be capable of resisting the adverse effects of natural forces like wind, rain and heat.
Hardness: The stone used in floors and pavements should be able to resist abrasive forces caused by the movement of men and materials over them.
Toughness: Building stones should be tough enough to sustain the stresses developed due to vibrations.
Specific Gravity: Heavier varieties of stones should be used for the construction of dams, retaining walls, docks and harbours.
Porosity and Absorption: Building stone should not be porous.
Dressing: Giving the required shape to the stone is called dressing. It should be easy to dress so that the cost of dressing is reduced.
Appearance: The stones to be used for face work, where appearance is a primary requirement, the colour and ability to receive polish are important factors.

Uses of Stones

Stones are used in the following civil engineering constructions:

Stone masonry is used for the construction of foundations, walls, columns and arches.
Stones are used for flooring.
Stone slabs are used as lintels and even as roofing materials.
Stones with a good appearance are used for the facades of buildings. Polished marbles and granite are commonly used for facades.
Stones are used for paving roads, footpaths and open spaces around the buildings.
Stones are also used in the construction of piers, abutments of bridges, dams, and retaining walls.
Crushed stones with gravel are used to provide a base course for roads. When mixed with tar, they form a finishing coat.

Also Read: Building construction | Types of Building construction

Bricks

Bricks, as engineering materials, are obtained by moulding good clay into a block, which is dried and then burnt.

Manufacture of brick started with hand moulding, sun drying and burning in clamps. A considerable amount of technological development has taken place, with better knowledge about the properties of raw materials, better machinery and improved techniques of moulding, drying and burning.

Types of Bricks

Bricks may be broadly classified as:

Building Bricks: These bricks are used for the construction of walls.
Paving Bricks: These are vitrified bricks and are used as pavers.
Fire Bricks: These bricks are specially made to withstand furnace temperatures. Silica bricks belong to this category.
Special Bricks: These bricks are different from commonly used building bricks with respect to their shape and the purpose for which they are made. Some of these bricks are specially shaped bricks, facing bricks, Perforated building bricks, Burnt clay hollow bricks, Sewer bricks, and resistant bricks.

Properties of Bricks as Engineering Materials

Below are the required properties of good bricks:

Colour: Colour should be uniform and bright.
Shape: Bricks should have plane faces. They should have sharp and true right-angled corners.
Size: Bricks should be of standard sizes as prescribed by various codes, such as British Standards, Chinese standards and Indian Standards.
Texture: They should possess a fine, dense and uniform texture. They should not possess fissures, cavities, loose grit and unburnt lime.
Soundness: When struck with a hammer or with another brick, it should produce a metallic sound.
Hardness: Finger scratching should not produce any impression on the brick.
Strength: The Crushing strength of the brick should not be less than 3.5 N/mm2. A field test for strength is that when dropped from a height of 0.9 m to 1.0 m on a hard ground, the brick should not break into pieces.
Efflorescence: Bricks should not show white patches when soaked in water for 24 hours and then allowed to dry in the shade.
Thermal Conductivity: Bricks should have low thermal conductivity, so that buildings built with them are cool in summer and warm in winter.
Sound Insulation: Heavier bricks are poor sound insulators, while lightweight and hollow bricks provide good sound insulation.
Fire Resistance: The Fire resistance of bricks is usually good. In fact, bricks are used to encase steel columns to protect them from fire.

Classification of Bricks Based on Their Quality

As Engineering materials, the bricks used in construction are classified as follows:

First Class Bricks: These bricks are of standard shape and size. They are burnt in kilns. They fulfil all desirable properties of bricks.
Second-Class Bricks: These bricks are ground moulded and burnt in kilns. The edges may not be sharp and uniform. The surface may be somewhat rough. Such bricks are commonly used for the construction of walls which are going to be plastered.
Third-Class Bricks: These bricks are ground moulded and burnt in clamps. Their edges are somewhat distorted. They produce a dull sound when struck together. They are used for temporary and unimportant structures.
Fourth-Class Bricks: These are the over-burnt bricks. They are dark in colour. The shape is irregular. They are used as aggregates for concrete in foundations, floors and roads.

Uses of Bricks as Engineering Materials

As Engineering Materials, Bricks are used in the following civil engineering works:

As building blocks.
For lining of ovens, furnaces and chimneys.
For protecting steel columns from fire.
As aggregates in providing waterproofing to R.C.C. roofs.
For pavers for footpaths and cycle tracks.
For lining sewer lines.

Also Read: Water Pollution and Control: Everything You Need To Know

Lime

It is an important binding material used in building construction. When mixed with sand, it provides lime mortar, and when mixed with sand and coarse aggregate, it forms lime concrete.

Types of Limes as Engineering Materials

Fat lime: It is composed of 95 per cent calcium oxide.
Hydraulic lime: It contains clay and ferrous oxide.
Poor lime: It contains more than 30% clay

Uses of Lime

The following are the uses of lime in civil engineering works:

For whitewashing.
For making mortar for masonry works and plastering.
To produce lime sand bricks.
For soil stabilisation.
As a refractory material for lining open hearth furnaces.
For making various types of cement.

Also Read: Everything You Need To Know About Water Quality

Cement

Cement is a commonly used binding material in the construction industry.

The cement is obtained by burning a mixture of calcium and clay materials at a very high temperature and then grinding the clinker to produce a fine powder.

Types of Cement

In addition to ordinary Portland cement (OPC), there are many varieties of cement. Important varieties are briefly explained here:

White Cement: The cement, when made free from colouring oxides of iron, magnesium and chlorine, results in white cement. White cement is used for floor finishes, skimming especially on external walls, plastering, and ornamental works.
Coloured Cement: The cements of desired colours are produced by intimately mixing pigments with ordinary cement. These cements are used for giving finishing touches to floors, walls, window sills, roofs, etc.
Quick-Setting Cement: Quick-setting cement is produced by reducing the percentage of gypsum and adding a small amount of aluminium sulphate during the manufacture of cement. This cement is used to lay concrete under static or slowly running water.
Rapid Hardening Cement: This cement can be produced by increasing lime content and burning at high temperature during the manufacturing of cement.
Low Heat Cement: In mass concrete works like the construction of dams, the heat produced due to the hydration of cement will not get dispersed easily. This may give rise to cracks. Hence, in such constructions, it is preferable to use low-heat cement.
Pozzolana Cement: Pozzolana is a volcanic powder cement. It is used for mass concrete works. It is also used in sewage line works.
Expanding Cement: This cement expands as it sets. This is used for filling the cracks in concrete structures.
High Alumina Cement: It is manufactured by calcining a mixture of lime and bauxite. It is more resistant to sulphate and acid attack. It develops almost full strength within 24 hours of adding water. As an Engineering material, it is used for underwater work.
Blast Furnace Cement: In the manufacture of pig iron, slag is a waste product. This cement is durable, but it gains its strength slowly and hence needs a longer period of curing.
Acid-Resistant Cement: This cement is produced by adding acid-resistant aggregates such as quartz, quartzite, sodium silicate or soluble glass. This cement has good resistance to the action of acid and water. It is commonly used in the construction of chemical factories.
Sulphate-Resistant Cement: It is used in the construction of structures which are likely to be damaged by alkaline conditions. Examples of such structures are canals, culverts, etc.

Properties of Ordinary Portland Cement

Chemical properties: Portland cement consists of the following chemical compounds: Tricalcium silicate – 40%, Dicalcium silicate – 30%, Tricalcium aluminate – 11%, Tetracalcium aluminate – 11%, and there may be small quantities of impurities present, such as calcium oxide (CaO) and magnesium oxide (MgO).
Physical properties: The following physical properties should be checked before selecting a Portland cement for the civil engineering works. The physical properties to be checked are Fineness, setting time, Soundness, Crushing strength, and Fineness properties.

Uses of Cement

As Engineering Materials, the following are the uses of cement:

Cement slurry is used for filling cracks in concrete structures.
Cement mortar is used for masonry work, plastering and pointing.
Concrete is used for the construction of various structures, such as buildings, bridges, water tanks, tunnels, docks, harbours, etc.
Used to manufacture lamp posts, telephone posts, railway sleepers, piles, and so much more.
For manufacturing cement pipes, garden seats, dustbins, flower pots, etc., cement is commonly used.
It is useful for the construction of roads, footpaths, courts for various sports, etc

Also Read: Cracks In The Building: The Complete Tips for Engineers

Sand

Sand is used as a base course to place flooring tiles and get a level surface. In the construction industry, sand is used as an inert material in mortar and concrete.

Sand is a natural product obtained from river sand and pit sand. Sea sand should not be used in making mortar and concrete for the following reasons:

It contains salt, and hence, the structure remains damp. The mortar is affected by efflorescence, and then blisters appear.
It contains shells and organic matter, which decompose after some time and reduce the strength and life of mortar and concrete.

Sand can be obtained artificially by crushing stones, too. In crushing stone to get coarse aggregates, it is obtained as a by-product.

The small particles of crushed stone form artificial sand for construction activities. In constructing dams and bridges, artificial sand is very commonly used.

Uses of Sand

Sand is mainly used in mortar and concrete for the following purposes:

It subdivides the paste of binding material into thin films, allowing it to adhere and spread.
It fills up the gap between the two building blocks (mortar) and spreads the binding material.
Adds to the density of mortars and concrete.
Prevents the shrinkage of cementing material.
The cost of cementing material per unit volume is reduced as this low-cost material increases the volume of cementing material.
Silica of sand contributes to the formation of silicates, resulting in a hardened mass.

Properties of Good Sand

Sand to be used for construction purposes should have the following properties:

Sand should be free from oil, silt, and clay.
It should be clean and free from any organic matter.
It should be well graded.
Chemically, the sand should be inert.
Sand should be sharp, angular, and coarse.
Sand should be hard and durable to withstand loads without failure.

Also Read: Unit Operations for Wastewater Treatment: The Complete Guide

Steel

Steel is an alloy of ferrous metal with 0.25 to 1.5 per cent of carbon. The higher the carbon content, the harder the steel.

As Engineering Materials, Steel bars with circular cross-sections are mainly used as reinforcement to strengthen concrete structures globally.

There are two types of reinforcing steel used in the construction industry:

Mild Steel: It contains carbon up to 0.23 to 0.25%. It is available in diameters of 6, 10, 12, 16, 20, 25 and 32 mm. Its yield strength is 250 N/mm2, and Young’s modulus is 2 × 105 N/mm2.
High Tensile Bars: High tensile steel bars are made with 0.8 % carbon and 0.6 % manganese, apart from small percentages of silicon, sulphur and phosphorus. They are available in diameters of 2, 3, 4, 5, 6, and 7 mm, with tensile strengths of 1400N/mm2 to 1900N/mm2. The Young’s modulus of steel is also the same as that of mild steel.
High-Yield Tensile Steel: These bars are provided with rib deformation on the surface to improve the bond between concrete and steel. These bars are available in diameters 8, 10, 12, 16, 20, 25, 32, and 40mm.

Uses of Steel Bars as Engineering Materials

Steel bars are used as follows:

Mild Steel bars are commonly used as reinforcement in concrete. It is also used in window bars, for grills and for making steel gates.
High tensile bars are used as reinforcement in prestressed concrete structures.
High-Yield Tensile Steel is used as reinforcement since its strength in tension and bond is higher. These are also used as wind bars.
Its strength, durability, flexibility, and ability to be prefabricated make it ideal for a wide range of modern constructions, from skyscrapers to industrial sheds.

Properties of Steel Bars

As Engineering Materials, the properties that need to be considered by structural engineers when specifying steel construction products are:

Strength
Corrosion resistance
Conductivity
Toughness
Ductility
Weldability
Durability

Timber

Timber refers to wood used for construction works. It is available in various commercial sizes, such as planks, battens, posts, beams and can be used in any engineering work.

Timber was used as a building material even by primitive man. Many ancient temples, palaces and bridges built with timber can be seen today.

Properties of Good Timber

The following are the properties of good timbers:

Colour: It should be uniform.
Odour: It should be pleasant when cut freshly.
Soundness: A clear ringing sound when struck indicates the timbers are good.
Texture: The Texture of good timbers is fine and even.
Grains: In good timber, grains are close.
Density: The higher the density, the stronger the timber.
Hardness: Harder timbers are strong and durable.
Warping: Good timber does not warp under changing environmental conditions.
Toughness: Timber should be capable of resisting shock loads.
Abrasion: Good timber does not deteriorate due to wear. This property should be looked into if timber is to be used for flooring.
Strength: Timber should have high strength in bending, shear and direct compression.
Modulus of Elasticity: Timber with a higher modulus of elasticity is preferred in construction works.
Fire resistance: A good timber should have high resistance to fire.
Permeability: Good timber has low water permeability.
Workability: Timber should be easily workable. It should not clog the saw.
Durability: Good timber is capable of resisting the action of fungi and insect attack
Defects: Good timber is free from defects like dead knots, shakes and cracks

Preservation of Timber

Preservation of timber means protecting the timber from fungal and insect attacks so that its life is extended.

Timber is to be seasoned well before the application of preservatives. The following are the widely used preservatives:

Tar
Paints
Chemical salt

Uses of Timber

Timber is used for the following engineering works:

For heavy construction works such as columns, trusses, and piles.
For light construction work such as doors, windows, flooring and roofing.
Other permanent works such as railway sleepers, fencing poles, electric poles and gates.
Used for temporary works in construction, such as scaffolding, centring, shoring and strutting, and packing of engineering materials.
Decorative work such as showcases and furniture.
For bodies of buses, lorries, trains and boats.
For industrial uses such as pulp (used in making paper), cardboard, and paper.
Used for making sports goods and musical instruments.

Also Read: Shallow Foundations For Medium Structures: A Quick Guide

Concrete

Concrete is more than just a mixture — it is the foundation of modern civilisation. From ancient Roman aqueducts to today’s tallest skyscrapers, concrete remains the most versatile and indispensable construction material in history.

At its core, concrete is a composite material made by combining the following materials:

Cement – the binder material that glues everything together.
Fine aggregates (sand) – for workability and uniformity.
Coarse aggregates (gravel) – for the strength and stability of the structure.
Water – the activator that starts the chemical reaction known as hydration. Water to be used for concrete should be clean and free from oil and other impurities.

Small quantities of admixtures such as air-entraining agents, waterproofing agents, and workability agents may also be added to impart special properties to concrete.

Plain Cement Concrete

The intimate mixture of cement, sand, coarse aggregate and water is known as plain cement concrete.

This type of cement is used where only compressive strength is needed and tensile strength is not needed.

Reinforced Cement Concrete (RCC)

Concrete is good at resisting compressive stress but is very weak in resisting tensile stress.

Hence, reinforcement is provided in the concrete wherever tensile stress is expected. The best reinforcing material is steel, since its tensile strength is high and the bond between steel and concrete is good.

Since the elastic modulus of steel is quite high compared to concrete, the force developed in steel is high.

A cage of reinforcements is prepared according to the design requirements, kept in the formwork, and then green concrete is poured.

After the concrete has hardened, the formwork is removed. The composite material of steel and concrete, now called R.C.C., acts as a structural member and can resist tensile as well as compressive forces efficiently.

Pre-Stressed Concrete (PSC)

In prestressed concrete elements, calculated compressive stresses are introduced in the zone where tensile stresses are expected when the element is put to use.

Thus, in bridge girders, the bottom side of the beam develops tensile stresses when the deck slab is placed and vehicles start moving on the bridge.

Hence, before the girder is placed in its position, compressive stresses are introduced on the bottom side.

This is achieved by pulling the high-tensile wires before concrete is poured in the formwork of the beam and releasing the pull only after the concrete hardens (pretensioned pre-stress concrete).

Pre-Cast Concrete

Usually, concrete structures are built by casting them in their final position on the site by providing formwork, pouring concrete and then removing the formwork.

It is called cast-in-situ construction. If concrete elements are cast in factories or elsewhere and transported to their final destination, they are known as precast elements.

Since the elements are cast in factories where controls are better, they are superior to cast-in-place elements. However, the disadvantage is the cost of transportation and achieving desired connections on site.

Uses of Concrete as Engineering Materials

Concrete, as one of the engineering materials, can be used as follows:

Uses of plain cement concrete are listed below:

For a simple foundation base for the wall footings and column footings, where tensile stresses are minimal.
As well as concrete to get a hard and even surface on the window.
As coping concrete over the parapet walls.
For making pavements.

R.C.C. is used as a structural member wherever bending of the member is expected. The common structural elements in a building where R.C.C. is used are: footings, columns, foundations, staircases, roof slabs, and beams.

Furthermore, RCC is used in the construction of dams, water tanks, bridges, retaining walls, docks and harbours, multi-storey buildings, chimneys, and underwater structures.

Prestressed concrete is commonly used in the following structural elements.

Beams and girders.
Slabs and grid floors.
Pipes and tanks
Poles, piles, sleepers and pavements.
Shell and folded plate roofs.
Long-span bridges.
High-rise buildings.

Lastly, Precast concrete is used:

Pipes and tanks
Poles, piles, sleepers and pavement
Lintel beams
Beams and girders
Building blocks
Wall panels
Manhole covers

Properties of Good Quality Concrete

Good quality concrete must:

have the correct mix proportions,
use well-graded aggregates,
Use clean and dry aggregates,
have the correct water-cement ratio,
have adequate but not excessive workability for the circumstances,
be properly and sufficiently mixed,
not segregate during mixing or transportation,
be well compacted,
be adequately cured,
be free from shrinkage cracks,
be durable and weather-resistant,
be of sufficient strength and fit for purpose.

Why Concrete Matters

In general, concrete matters because:

Concrete can be moulded into any shape before hardening.
Develops immense compressive strength with time.
It is durable, versatile, and economical.
Its adaptability makes it the backbone of foundations, beams, slabs, bridges, and dams.

Final Thought on Basic Civil Engineering Materials

Concrete isn’t one-size-fits-all. Over the course of decades, engineers have tailored concrete into specialised forms to meet various structural and environmental demands. Each type has unique properties that make it suitable for specific applications.

Think about it: over 10 billion tons of concrete are used globally each year — more than any other man-made material. Without concrete, our modern cities would not stand so far.

So far, I think you’ve learned something. Engineering materials is a long topic that I can continue at another time.

Today I have only mentioned stones, bricks, lime, cement, sand, steel, and timber. I know in engineering materials, there are many things I have left out…I will continue later.

Continue to read this post regularly to stay updated on the continuation of this topic.

Join the conversation by replying on Bluesky.

That’s all.

If you liked this article, please join WebsiteForEngineers on Twitter, Facebook, TrueSocial, Pinterest, BlueSky, and in our WhatsApp channels.

Bricks, Lime, Sand, Stones, Timber