Mortar is the substance that is used to join bricks when constructing a wall. Mortar is used for masonry construction, flooring, plastering, and finishing, which will be in a wet state for the application. This kind of mortar is made up of the raw materials that are needed to make a substance that can be used to make a strong brick wall. The dry mix is hugely different from job-site mortars. Dry-mix mortars are accumulated in a special factory with dedicated facilities on batching and blending of all the necessary ingredients in the controlled process. In this way, different types of dry-mix mortar products with well-defined properties and performance to meet specific requirements and applications can be produced.
Dry mix products provide excellent technical properties to meet the stringent performance requirements which are common in the current construction scenario. The use of dry mix mortar products will be cost effective by reducing the potential construction problems with the long-term integrity of structures with a simple materials approach.
Raw Materials for Dry-Mix Mortar
Most of the dry-mix mortar products require only the addition of potable water and mixed with a simple mixer to produce high-quality fresh mortars. Although the dry mortars are relatively easy to prepare and use, the ingredients and their proportions of each product are sometimes very complicated. Most of the high-performance products are usually based on extensive development process and tests in order to achieve the designed materials properties.
The raw materials used for dry-mix can generally be grouped into four main categories (binders, fillers, chemical additives, pigments) and some of the basic generic types are listed below:
– Ordinary Portland cement (OPC)
– High alumina cement (HAC)
– Ground granulated blast furnace slag (GGBFS)
– Pulverized fuel ash (PFA)
– Micro silica
– Hydrated lime
– Silica sand
– Quartz sand
– Limestone powder
– Silica powder
– Expansion clay
– Cellulose fibre
– Polypropylene fibre
– Cellulose esters
– Thickening agents
– Air entraining agents
– Accelerating agents
– Retarding agents
– Defoaming agents
– Hydrophobic agents
– Plasticizing agents
– Shrinkage compensation agents
– Inorganic pigments
– Organic pigments
Most of the dry-mix mortar products contain both mineral cementitious binder (e.g. OPC) and the polymer binder (e.g. re-dispersible powder) and they are normally packed in bags after mixing in the factory. Hence, the dry-mix mortar products are also known as Premixed or Pre-bagged Polymer Modified Cementitious Mortar.
Dry mix mortar has a wide category of products that includes dry mix products and construction chemicals in dry form. Globally, manufacturers of construction chemicals have the entire dry mix mortar product range. However, they are not specifically categorised as dry mortar manufacturers as they also have liquid and resin based products.
Some of the Dry Mix Mortar Products Include
1. Plastering – internal / external
2. Thin joint mortars
3. Floor screeds
5. Cement grouts
6. Tile adhesives
7. Tile joint fillers
8. Waterproofing products
9. Crack fillers and repair materials
While Portland Cement continues to be the most widely used binder, with the rising emphasis on sustainable building strategies, the use of other types of materials such as Pulverized fuel ash (PFA) and Ground granulated blast furnace slag (GGBFS) is also on the increase. Based on application, different technical terms are used to refer to dry mix mortar products. For example, the simple masonry dry mix mortar consists of a mixture of aggregates with the binder, chemical additives, and polymers. Similarly, for large volume mortar applications of laying bricks or blocks,” Renders” are used. “Plasters” are the mortars used for an interior application. Exterior Insulation and Finishing Systems (EIFS) are flow-able, cementitious or anhydrite-based floor leveling material for thicker floors in the range of 20mm to 50mm. Self-leveling underlayment (SLU) is the low viscosity, a self-flowing material used for finishing floors, in the thickness range 2mm to 5mm. “Tile adhesives” for fixing of tiles, “Joint fillers” , such as tile grouts, and “Waterproofing slurries” for a protection of storage tanks and concrete pipes have also become popular in recent times.
Among the lot, bricklaying mortars are popular across European countries. These most basic types of mortars, be-cause of their ability to offer consistent quality and reduce labour on construction sites are in demand. Wall renders and plasters are also widely used dry mix mortar products. They are typically delivered in silos to the construction site. The render is sucked from the silo, through a hose, using specialized equipment meant for the purpose, and pumped onto walls. Floor screeds are another popular category. Millions of square feet of floor screed are placed globally. One of the major advantages with an hydrite superplasticizer based floor screeds are that over 200 sq.m of screed can be placed without joints. This is because of their low shrinkage. Quicker surface maturity is also achieved because of their property to dry out fast.
Tile adhesives are another area where dry mix mortar products are now being increasingly sought after. Thanks to the availability of the latest dry mix mortar technology based tile adhesives, the thin-bed fixing technique is being instead of the conventional thick-bed method. While the thin-bed method is known to cost more, the fact that it helps in superior adhesion, again due to the low shrinkage factor, results in savings in the long run. Similarly, joint fillers, such as tile grouts, used to fill voids in tile setting and between plasterboards, are another growing market segment, so far as dry mix mortar products are concerned. Powder paints, delivered in silos to the construction site and which are applied using machine spraying is another category among dry mix mortar products, that is fast finding an increasing number of takers nowadays.
Factors driving the demand
One key factor that has been driving demand is the ability of these products to save on labour costs. With the use of specialized application equipment, substantial improvement in workmen efficiency and output has been reported due to the use of these products. For countries like India suffering from a crunch in construction labour, adoption of this technology could be the answer. Ease of application is another important factor that works in favour of dry mix mortar products. This is one more factor that is especially important in countries like India, where a majority of the construction workers are unskilled, with very low levels of education.
Another important factor that can further drive the demand for dry mix mortar-based products is the pressure from various quarters to deliver buildings that are durable and require very low maintenance. Their ability to deliver on the promise of consistency of quality is what has been a major reason for the remarkable growth in demand for these products. The need to increase the sustainability quotient of buildings and ensure long-term functional durability is the demand nowadays from specifiers and dry mix mortar technology is what is they are looking towards for delivering on this key aspect.
1. Factory made dry mortar with quality certification as per standards
2. Usage of quality raw materials as per the applicable standards
3. Green products for environment sustainability
4. Educating the users on good construction practices and quality of the contents
5. Pursuing the industry to deliver structures with good standards
6. Testing of products for all technical parameters and creating awareness about the technical attributes to users for choosing the right product
7. Proper quantification of materials and reduction in wastage
8. Hassle free and ease of application and usages
Dry Mix Mortar Production
Modern Dry-Mix Production Plant For advanced dry mortar manufacturing plants with modern facilities, the production sequences are almost fully automatic with all the devices controlled 6 and monitored by electronic sensors. The automatic dosing system is usually very precise with extremely high accuracy especially for batching high-performance chemical additives. The batching sequences and mixing cycles are specially designed for each product to ensure the powdery ingredients are blended to form a homogeneous mixture within the batch. For a highly efficient modern plant, the mixing time for each batch may be as short as 2 to 5 minutes depending on type and complexity of the product. Since the production is automatic and closely monitored by electronic devices, the product consistency is expected to be high provided that a tight quality control on the raw materials and products is performed.
In India, the trend of dry mix mortar is catching up for the last few years and is showing a good prospect for future in the construction industry. By using dry mortar products, the quality, and speed of construction increases. The market is yet to see its full potential but with an increasing interest of the manufacturers its getting adopted more as the days goes by.
The Key players of this system include the name such as- Ramco Cements Limited, Magicrete Building Solutions Pvt. ltd, Citadel, Green Built, Perlecon, Ultratech,Frigmaires Engineers, , Buildmate Projects Pvt. Ltd, , Saint Gobain Weber. These all are national players.
Apart from them there also firms some local players such as, DICO FIX, PNEUCON PROCESS TECHNOLOGIES, Laxmi En-fab Pvt. Limited,The, Ready Mix Construction Machinery Pvt. ltd, Robuster Constructware LLP, S. F. Engineering Works, 360 Degree Global Equipments Pvt Ltd, Avcon Technics Private Limited, Speed Dry Mix India Pvt Ltd. etc
The non-availability of river-sand and the increase in labour cost and non-availability of skilled labour have necessitated the requirement of ready-made building products. This scenario was well understood by major cement manufacturers globally and in India for a forward integration business model through dry mix plants. Considering cement volumes and the percentage cement volume for masonry applications, the higher rate of conversion of conventional cement mortar system to factory made dry mortar is possible in the near future. the need of the hour is the adaption of the technology based on local requirements and availability of raw materials. There is also a need to increase awareness levels about the benefits of using the technology. There needs to be a sustained campaign organized in order to drill the fact that here is a technology that can not only enable improvement in construction productivity, but it will also help enhance building quality, while at the same time being easy to apply.