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What is Colgrout Masonry?

Colgrout entails doing rubble masonry in big structures like dams. In this method of construction, big stones are arranged in the masonry structures and are properly packed with smaller stones of distinct sizes to achieve stable dry masonry without the implementation of mortar to hold the stones together. The spaces are then grouted with cement mortar using pipes to obtain a strong and dense structural masonry, which does not allow water to seep, even when under a lot of pressure.

Grout used for this type of construction is made using sand, cement, superplasticizers, and fly ash. Ingredients are mixed in fast-rotating mixers to create a colloidal gel-like product, which can easily flow into the gaps and interstices between the stones. It also binds them into a homogeneous mass. In big structures, colgrout masonry is regarded as economical, faster, and stronger compared to other construction methods.

Mason, bricklayer worker is using red blocks

Materials Used in Colgrout Masonry

As aforementioned, different materials have to be used to ensure colgrout masonry goes according to plan. This part of the article looks at exactly that.

  • Cement

The type of cement usually used is Portland cement and super sulfated cement. These types of cement work great in dams and other big structures. Other types of cement may be required for use in dam masonry.

  • Sand

The sand used in colgrout masonry should be dense, hard, and durable. It should not contain harmful elements like alkalis, coal, salts, and iron pyrites or organic impurities like shale and mica.

  • Stone

The stone used should be of high quality. Common types of stones used include basalt and trap. These stones should be hard, tough, durable, sound, and clean. They should also be free from decay, coatings, soft seams, weathered faces, cracks, holes, and stains.

  • Water

The water used to mix mortar and grout and wash the stones should meet the given standards by building authorities. It should be clean and free from objectionable quantities of matter, salts, organic matter, silt, and other injurious materials.

  • Fly Ash

Fly ash is as fine as Portland cement. It improves the workability of cement or mortar, meaning it is an important element in colgrout masonry.

Equipment and Tools Used in Colgrout Masonry

This type of construction makes use of a variety of equipment and tools to ensure everything goes according to plan. This part of the article looks at exactly that.

  • Colgrout Mixer

The most common mixer used is the double drum mixer, which consists of two mixing units and a power unit that is mounted on a suitable chassis. The mixer has different mixing units, which consist of a hopper tank that is connected to a casting in the same form as that of a centrifugal pump.

The first part of the mixer produces water and cement slurry. In the second unit, the slurry is mixed with sand, producing cement, water, and sand grout. In the cement mixing unit, a rotor disk rotates at 1500-2000rpm. The rotor creates a pumping action that induces cement and water to pass at high speeds via the narrow gap between the stator and the rotor. The rotor in the second unit is like a star designed for wetting the sand with water and cement and discharge the colgrout through a hosepipe at a significant amount of pressure. Water is measured by a measuring meter or tank, meaning the water to cement ratio is under definite control.

  • Construction Tools Used

Colgrout masonry makes use of different construction tools such as a square, trowel, mallet, iron hammer, claw tool, chisels, pick, spalling hammer, bevel, spirit level, and many more.

Benefits of Colgrout Masonry

Colgrout masonry is a game-changer in the building industry because it offers a faster method of construction compared to traditional masonry construction techniques, especially in dams. Since the construction is done faster, the project can be commissioned a lot earlier, meaning that time and money can be saved in that process. In addition, the labor required for colgrout masonry is less compared to other types of construction. The construction technology here is standardized and the permeability is very less because the masonry is homogenous. The impermeability results to reduced cost of grouting and maintenance because of seepage and leaching materials.

Due to its simplicity and significance, colgrout masonry has proven to be a great type of construction. Anyone planning to build should definitely consider this construction method. However, if it is your house or building being built, you want to leave this worry to the professionals, as they already know the best building method for you.