How to Make Mortar: A Comprehensive Guide
Making mortar, also known as mastic or concrete mixture, is a crucial process in the construction industry. It serves as the bonding agent between blocks, bricks, or concrete elements, holding them together and providing strength to structures. In this article, we will guide you on how to make mortar, exploring its composition, importance, and step-by-step preparation.
Composition of Mortar
Mix of Cements:
- Portland Cement (1 part) is the primary binding component.
- Lime Cement (0-2 parts) is sometimes used for hydraulic binding in specialized applications.
Filler Materials:
- Sand (5-6 parts) absorbs water, making the mix easier to spread and form.
- Aggregate (optional), such as pebbles or granite dust, may be used to enhance the mix.
Additives (optional):
- Hydration reduces water intake.
- Air entrainers prevent water migration through the concrete.
- Admixtures, such as chemical accelerants, may enhance workability.
Importance of Mortar
Mortar is crucial for:
• Structural Integrity: Binding and supporting building structures, such as walls, bridges, and roads.
• Fire Resistance: Provides fire-resistance features to protect people and valuables.
• Wind and Weather Resistance: Combines with cement to repel water, wind, and weather.
Materials and Equipment Needed
- Measuring Tubs
- Whisk or Tongs
- Trays or Ramps for Pouring
- Scales (Electronic or Digital)
- Lime-Sand Sieves (medium-grained, 14-mesh, or a close tolerance of 300 microns)
Step-by-Step Preparation of Mortar
Follow this simple formula:
| Amount | Component |
|---|---|
| 1.00 part | Port |
| 4.0-4.5 parts | Filler Sand |
Concrete Preparation:
- Sift Lime-Cement, ensuring optimal blending and even mixing.
- Dry for at least 30 minutes before starting.
- Scale material weights for accuracy and precision.
- Combine ingredients:
- Add the Port Cement directly into the mixer or construction zone.
- Pour calculated sand, Lime Cement, or aggregates over the Port cement, using your hands to gradually blend or whisk slowly until combined.
- Reverse steps 2 and 1 if adding Lime cement and aggregate to Port.
- Workability Checks: Use your hands, spatula, or fingers to mix. Perform wet touch, scratch, slump, and spreading tests (<1000 μF, <15 mm and >40 μF slumps, and <120 cm3/30 ml). If workability results do not match desired results, adjust your mix before using it for construction.