The cement concrete pavement is the most widely used flexible pavement in the world. The use of concrete for pavements has been around for nearly 200 years and it’s durability, strength and economy are well established. In India Cement Concrete Pavement is being extensively used as base course and sub-base course in road construction owing to its superior properties and advantages it offers.

The Indian Standard Specifications IS:456 (Plain & Reinforced Cement Concrete) recommended concrete as the most suitable material for the construction of pavements since it provides a rigid wearing surface, capable of withstanding high traffic loads while providing smooth riding characteristics.

The use of Portland Pozzolana Cement (PPC) in concrete pavements will help in getting rid of acid rain and air pollution due to the use of cement.

As the world develops further, more and more buildings are constructed. And as the number of buildings increases, so does the need for cement. Cement is a very important component in making cement concrete pavements. As you all know, cement is made by heating limestone (calcium carbonate) with small quantities of other materials (such as clay) to 1450°C in a kiln. The resulting hard substance, called ‘clinker’, is then ground with a small amount of gypsum into a powder to make ‘Ordinary Portland Cement’, the most commonly used type of cement (often referred to as OPC).

Portland cement is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout. It was developed from other types of hydraulic lime in England in the mid 19th century and usually originates from limestone. It is a fine powder produced by heating limestone and clay minerals in a kiln to form clinker, grinding the clinker, and adding small amounts of other materials. Several types of Portland cement are available. The most common, called ordinary Portland cement (OPC), is grey, but white Portland cement is also available

In the present cement concrete pavements are in extensive use. The materials used for making cement concrete pavement is ordinary Portland cement, coarse aggregate, fine aggregate and water. The manufacturing of cement involves a process like crushing, grinding, drying, burning and packaging. These processes will release some amount of dust particles into atmosphere.

The dust particles emitted from the cement plants are harmful to human beings and may cause severe damage to human systems when inhaled or consumed in large quantities.

The constituents of ordinary Portland cement are lime, silica, alumina and iron oxide. During the manufacturing process of ordinary Portland cement these constituents are mixed in correct proportion depending on the requirement and then crushed in jaw crusher and roller crusher to get it into granular form. Then powdered form is obtained by grinding the crushed material in ball mill or tube mill. Then it is mixed with gypsum (CaSO4)2H2O and ground again in tube mill to get finished product i.e.,Portland cement.

(Image courtesy: https://www.britannica.com/technology/cement)

Here we are all set to tell you how we are making the world a better place and how the cement industry is fighting the war against pollution in all the possible ways they can.

Kudos to you if you have already read our previous article on cement industry, if not then click here to read it. In this article we will discuss about the most common cementitious material used for making concrete pavements, which are nothing but our roads. This article will help you get an idea about what is going on with your roads and why you should not feel bad about them before it’s too late.

Before getting into the topic let us first understand what a concrete pavement is? Concrete pavement is nothing but the surface layer of our roads, which has been constructed by pouring concrete on a well prepared base course. This base course is usually made up of soil or sub-grade material. The layer above this base course is called as sub-base course, which acts as a cushion between the base and the pavement materials so that these two layers don’t rub against each other, due to which eventually potholes may develop in your road.

The layer above this sub

The cement industry is known to be one of the most important and largest greenhouse gas emitters. The primary source of carbon dioxide (CO2) emissions from a cement plant is the decomposition of limestone in the kiln. The energy needed to drive this process is usually supplied by burning fossil fuels such as coal, natural gas, oil, or petroleum coke.

The world’s largest industries are widely recognized as the most polluting on earth. The steel industry, with 2.5% of global CO2 emissions, and the cement industry, with 5%, combine for 7.5% of all annual global CO2 emissions. Combined, these two industries alone produce more CO2 than all of Germany (8% of global emissions).

While steel production generates CO2 as a byproduct of producing iron from iron ore, cement production generates CO2 directly in the chemical process which converts limestone into clinker (the intermediate product used in the manufacture of cement).

A single cement plant in China’s Hebei province emits more than 50kg of small particulates (PM 2.5) per tonne of clinker made, according to local environmental groups citing official monitoring data released last year. That compares with 5kg per tonne emitted by a leading European producer and

One of the major problems with the use of cement concrete is its high alkalinity, leading to high pH, which results in several chemical reactions and generation of effluents.

The most significant chemical reaction is the reaction that takes place between water and cement, which is responsible for the generation of calcium hydroxide. This calcium hydroxide reacts with carbon dioxide to form calcium carbonate. The formation of this calcium carbonate is responsible for increasing the pH value of the soil.

The increasing pH values are responsible for the self-neutralization process of acidic soils. Because of this self-neutralization process, there is a decrease in the amount of acidity in rainwater, which has been falling on soils and hence reducing acid rain and air pollution due to it.