The Chemistry of Cement Haley Graham

cement composition

Cement bonded composites are made of hydrated cement paste that binds wood or alike particles or fibers to make pre-cast building components. Various fiberous materials including paper and fiberglass have been used as binders.

Wood and natural fibres are composed of various soluble organic compounds like carbohydrates, glycosides and phenolics.

These compounds are known to retard cement setting.

Therefore, before using a wood in making cement boned composites, its compatibility with cement is assessed.

Wood-cement compatibility is the ratio of a parameter related to the property of a wood-cement composite to that of a neat cement paste.

The compatibility is often expressed as a percentage value.

Through the Looking Glass (2010) - Materials Documentary

Plastic

The term plastics covers a range of synthetic or semi-synthetic organic condensation or polymerization products that can be molded or extruded into objects or films or fibers.

Their name is derived from the fact that in their semi-liquid state they are malleable, or have the property of plasticity.

Plastics vary immensely in heat tolerance, hardness, and resiliency.

Combined with this adaptability, the general uniformity of composition and lightness of plastics ensures their use in almost all industrial applications today.

plastic product

Glass

Glassmaking is considered an art form as well as an industrial process or material.

Clear windows have been used since the invention of glass to cover small openings in a building.

They provided humans with the ability to both let light into rooms while at the same time keeping inclement weather outside.

Glass is generally made from mixtures of sand and silicates, in a very hot fire stove called a kiln and is very brittle.

Very often additives are added to the mixture when making to produce glass with shades of colors or various characteristics (such as bulletproof glass, or light emittance).

The use of glass in architectural buildings has become very popular in the modern culture.

Glass "curtain walls" can be used to cover the entire facade of a building, or it can be used to span over a wide roof structure in a "space frame".

glass staircase

These uses though require some sort of frame to hold sections of glass together, as glass by itself is too brittle and would require an overly large kiln to be used to span such large areas by itself.

Metal

Metal is used as structural framework for larger buildings such as skyscrapers, or as an external surface covering.

There are many types of metals used for building.
Steel is a metal alloy whose major component is iron, and is the usual choice for metal structural building materials. It is strong, flexible, and if refined well and/or treated lasts a long time. Corrosion is metal's prime enemy when it comes to longevity.

steel

iron ore

iron rod

The lower density and better corrosion resistance of aluminium alloys and tin sometimes overcome their greater cost.

aluminium alloy

tin ore

tin product

tin plating product

Brass was more common in the past, but is usually restricted to specific uses or specialty items today.

brass rod

Metal figures quite prominently in prefabricated structures such as the Quonset hut, and can be seen used in most cosmopolitan cities.

It requires a great deal of human labor to produce metal, especially in the large amounts needed for the building industries.

 Quonset hut

Other metals used include titanium, chrome, gold, silver. Titanium can be used for structural purposes, but it is much more expensive than steel. Chrome, gold, and silver are used as decoration, because these materials are expensive and lack structural qualities such as tensile strength or hardness.

gold

chrome

silver

titanium

Metal Properties

Brickwork Tutorial

Strange behaviour of sand

Masonry units

The properties of masonry units should comply with the requirements of relevant European standards (EN 771-1-6). 

Masonry units are classified into the following types: solid, perforated unit, hollow unit, cellular unit and horizontally perforated unit .

Properties of Sand

Mineral Composition, whether single mineral grains like quartz sand, or made up of other minerals or small rock fragments. Sands containing a large proportion of heavy minerals, such as rutile and zircon are mined as sources of titanium and zirconium. There are also sands rich in magnetite, suitable for treating as iron ore.

Grain size and size distribution (sorting). Well sorted sands (single sized) are useful for industrial applications, whereas sand with a wide distribution of grainsize is preferred for concrete manufacture (because a poorly sorted sand has less pore space, and less cement is needed in making concrete).

Porosity and permeability. Well sorted sand has a higher permeability, and is suitable for drainage materials and, especially if pure quartz sand, for water filtration.

Grain shape (angular, subangular or rounded). More angular sand is preferred for concrete manufacture, and well-rounded sand is preferred for filtration sand.

sand

Concrete

Concrete is a composite building material made from the combination of aggregate and a binder such as cement.

The most common form of concrete is Portland cement concrete, which consists of mineral aggregate (generally gravel and sand), portland cement and water.

After mixing, the cement hydrates and eventually hardens into a stone-like material.

When used in the generic sense, this is the material referred to by the term concrete.

For a concrete construction of any size, as concrete has a rather low tensile strength, it is generally strengthened using steel rods or bars (known as rebars).

This strengthened concrete is then referred to as reinforced concrete.

In order to minimise any air bubbles, that would weaken the structure, a vibrator is used to eliminate any air that has been entrained when the liquid concrete mix is poured around the ironwork.

Concrete has been the predominant building material in this modern age due to its longevity, formability, and ease of transport.

Recent advancements, such as Insulating concrete forms, combine the concrete forming and other construction steps (installation of insulation). All materials must be taken in required proportions as described in standards.

concrete aggregate cement

concrete glossy cement

 concrete wall

Wood

A natural material for building dwellings for thousands of years, wood was also used to make Churches in the past. The main problems with wood structures are fire risk and durability. Wood is an aesthetically pleasing material that never goes out of trend completely, though the current popularity of plastic is taking its place in many construction sites.

Free hires wood

taxus wood

wood fence texture

Stone

Stones used in construction can be divided into two category:
-natural: rocks that are obtained from the earth
-artificial: name for various kinds of synthetic stone products.

1. Natural Stones can be subdivide into 3 types:

(a)Igneous rock       
- rock that was deposited in a molten state of magma.

pumice

granite

basalt

(b)Sedimentary rock
 - rock deposited by the action of wind and ice
 - ex:

sand stone

limestone

dolomite

(c)Metamorphic rock
  - rock that was originally was igneous or sedimentary , heat and pressure which had change the properties of the rock
 - ex:

marbles

slate

quartzites

2. Artificial stones: made by crushing and grinding natural stone, then re-constituting it in a mould with cement mortar.
  - natural stones that is used for the manufacture of artificial stones are:
     (i) calcareous stone: dolomite, marble, limestone
     (ii) siliceous stone: sand, granite, quartzite


  - uesd for exterior house : walls, pavements, top roof flooring
  - ex:

 

Modena Granite stone

Verona Stone

 

What is Building Material?~

Building material is any material which is used for a construction purpose.

Many naturally occurring substances, such as clay, sand, wood and rocks,
even twigs and leaves have been used to construct buildings.

Apart from naturally occurring materials,

many man-made products are in use, 

some more and some less synthetic. 

The manufacture of building materials is an established industry in many countries and 

the use of these materials is typically segmented into specific specialty trades, 

such as carpentry, plumbing, roofing and insulation work.

They provide the make-up of habitats and structures including homes.

Installing rebar in a concrete floor during a pour