The reliability, durability and safety of a building in many respects depend on the quality of building materials that were used for its construction. That is why their choice should be approached very carefully. To pick up good building materials, you need at least a little orientation in a wide list of their technological properties and qualities. This article will discuss the types, applications and basic properties of building materials. In addition, you will learn about some of the innovations of the modern construction market.
Building materials evolution
Under construction materials are meant substances that are diverse in composition, state of aggregation and physical properties, which are used or can be used for the construction of various buildings and engineering structures. In the historical context, they arose precisely at the moment when the primitive man made his first primitive tools and thought for the first time about how to build a roof over his head.
Initially, mankind used what was at hand - wood, straw, clay, palm branches. Natural dyes were applied to the walls of caves and simple dwellings. In the ancient cities of the Middle East, ceramics was invented, which through Egypt penetrated into Western Europe. With the development of science and technology, completely new structural and finishing materials appeared.
In general, three historical stages can be distinguished in the evolution of the construction industry, each of which has its own set of materials:
- Wood, stone and brick (until the middle of the XIX century).
- Steel, glass, concrete (mid-19th - mid-20th centuries).
- Reinforced concrete, plastic, metal, artificial stone (from the second half of the twentieth century to the present day).
Further we will dwell in more detail on the basic properties of building materials and products. What are these qualities and how important is it to take them into account when building any building?
Classification of the basic properties of building materials
The construction business remains one of the most profitable today. The modern market offers an incredibly wide selection of various building materials, trim elements, mixtures and solutions. Almost dozens of the latest titles appear almost every year. And keeping track of all the new products in this market is not so simple.
Determining the basic properties of building materials is an extremely important task. Indeed, only because of this, from the whole variety of products offered, it is possible to choose precisely those materials that are ideal for the construction of a particular object. It is important to note that all these properties are not permanent. Moreover, they change under the influence of those conditions (natural, climatic, etc.) in which the building will be operated.
The main properties of building materials are usually divided into four groups:
- Physical (including hydrophysical and acoustic) - determine the nature of the interaction of a particular material with the environment.
- Mechanical - determine the resistance of the material to mechanical damage.
- Chemical - reveal the resistance of the material to various chemical influences.
- Technological - show how this or that material can be processed.
We consider in more detail each of the groups
Physical qualities
The main physical properties of building materials include the following:
- Density.
- Porosity.
- Hygroscopicity.
- Water resistance.
- Water permeability.
- Frost resistance.
- Fire resistance.
- Sound absorption.
Density is understood to mean body weight per unit volume. It is measured in kg / m 3 . The average density of various building materials varies widely. So, for natural wood it is about 1200 kg / m 3 , for stone products - from 2200 to 3300 kg / m 3 , and for steel - over 7500 kg / m 3 . No less important is the porosity index of the material. Moreover, not only the presence of pores, but also their size is taken into account.
Among the main properties of building materials, hygroscopicity (the ability of the rock to absorb and retain moisture), water resistance and water permeability (the ability to pass water under pressure) occupy a special place. These qualities are especially important in the construction of hydraulic structures, reservoirs, dams and river dams.
Mechanical qualities
We list the main mechanical properties of building materials. It:
- Hardness.
- Strength.
- Resistance to blows.
- Wear.
Hardness means the ability of a substance to withstand the penetration of an external body into it. For solid materials of mineral origin, a 10-point hardness scale (Mohs) has been developed. One ball in it corresponds to talc, and ten points correspond to diamond (see diagram below). Various methods are used to determine the hardness of metals and plastics (for example, the Brinell or Vickers method ).
Another important characteristic is strength. In particular, in construction, the strength limits of building materials for bending and compression are taken into account. The calculation of these parameters is important for determining the permissible loads on the structure. By the way, according to these indicators, all building materials are divided into two groups:
- Plastic - those that easily change their shape without the appearance of cracks (metals, plastic).
- Fragile - those that are very vulnerable to shock and have a low tensile strength in bending (brick, glass, concrete, natural stone).
Resistance is understood as the amount of work necessary for the complete destruction of the sample, and wear means the resistance of the material to shock and abrasion loads acting simultaneously. Both of these characteristics are the main properties of road building materials.
Chemical qualities
The chemical properties of building materials include:
- Adhesion.
- Solubility.
- The ability to crystallize.
- Chemical resistance.
Adhesion is the ability to combine liquid and solid substances, which is due to intermolecular interaction. Thanks to this quality, such building materials as cement arose. Solubility is the ability of a substance to create a special system (solution) with a liquid solvent. It depends on several factors - temperature, pressure, chemical composition of the substance.
The process by which crystals form from melts and solutions is called crystallization. It is widely used to obtain many stone materials of artificial origin.
The chemical stability of a building material is very important. It shows how much the material is able to withstand the destructive effects of various aggressive substances. For this, a special coefficient is calculated (as the ratio of the mass of the material after chemical exposure to the initial mass of the same material). The closer this coefficient is to unity, the more stable the substance is to an aggressive chemical environment.
Technological qualities
The technological properties of building materials include:
- Plastic.
- Viscosity.
- Weldability.
- Durability, etc.
All these properties express the ability of a material to perceive or not perceive certain technological operations in order to change its shape, size or density. They show how much the material can be machined, polished, and polished.
Examples of technological materials are clay and wood. Metals are less technologically advanced, although they can also be processed both in molten and cold conditions.
Classification of building materials
By the method of obtaining all building materials are divided into:
By their origin they are:
- stone;
- forest;
- metal;
- glass;
- polymer, etc.
In general, nine groups of building materials can be conditionally distinguished:
- Materials for the construction of the foundation and walls (concrete, brick, timber, booth and others).
- Materials for the roof (tile, slate, sheet steel, roofing material).
- Finishing materials (drywall, primers, plaster mixes).
- Decorative materials (paper wallpaper, parquet, laminate, artificial stone panels).
- Installation materials (nails, screws, staples, dowels).
- Mortars (cement, lime, adhesive mixtures, acoustic solutions).
- Polymer materials (plastic, polyethylene, polystyrene, polycarbonate).
- Insulating materials (sawdust, shavings, foam glass, mineral wool).
- Materials for road construction (asphalt, asphalt concrete, bitumen, paving stones).
Novelties of the construction market
The construction industry in our time is developing at a rapid and very rapid pace. Every year, a number of completely new building materials appear on this market. Let's briefly get to know the most interesting of these new products.
Foam glass is a material that was invented in the USA back in the 40s. However, it appeared in our market only in recent decades. It is produced at very high temperatures (up to 800-900 degrees). Granular foam glass is successfully used for wall insulation, foundation, as well as for thermal insulation of pipelines. After all, it can completely repeat any configuration of pipes. Perhaps this is the main property of the building material. In addition, foam glass has a very high compressive strength.
Colored brick is a building material, the appearance of which was cheered by all architects and designers. After all, it allows you to realize the most daring and most creative ideas. In addition, such a brick is able to maintain its original appearance for a long time. It is already widely used for facing high-rise buildings in many cities.
Another novelty of recent years is Corten steel. In construction practice, it appeared recently - in the early 2000s. Alloy steel sheets are highly durable and have an unusual appearance. They are widely used not only in industrial, but also in residential construction. In addition, Corten steel found its application in urban street art.
Finally…
To build a reliable and beautiful house - you need high-quality building materials. And in order to choose those, you need to be well versed in their properties. They are divided into four groups: physical, chemical, mechanical and technological. The most important properties of building materials include: density, strength, porosity, wear resistance, frost resistance and chemical resistance.