Why Choose White Portland Cement?

White portland cement

What exactly is White Portland Cement?

White Portland Cement, a variant of ordinary Portland Cement (OPC), distinguishes itself through its distinct white hue. Like OPC, it comprises primarily of limestone, clay, and gypsum, but with lower iron and manganese content, resulting in its pristine white coloration.

How is White Portland Cement manufactured?

The manufacturing process of White Portland Cement mirrors that of its gray counterpart, with the key difference lying in the raw materials’ composition. Precisely controlled proportions of limestone and other materials are finely ground and calcined at high temperatures to produce the signature white clinker.

What are the key properties of White Portland Cement?

  • Purity: Its exceptional whiteness makes it ideal for applications where aesthetics play a pivotal role.
  • Strength: White Portland Cement offers comparable strength characteristics to gray cement, ensuring structural integrity in diverse construction projects.
  • Versatility: From architectural concrete to decorative finishes, its versatility knows no bounds.
  • Durability: Resistant to discoloration and weathering, it maintains its pristine appearance over time.

Why should you opt for White Portland Cement?

  • Aesthetic Appeal: Achieve stunning architectural designs and vibrant color schemes, surpassing the limitations of traditional gray cement.
  • Design Flexibility: Embrace endless possibilities in decorative concrete, overlays, and precast elements, allowing for intricate detailing and customization.
  • Enhanced Visibility: Enhance visibility in low-light environments or underground structures, ensuring safety and visibility without compromising aesthetics.
  • Heat Reflectivity: White Portland Cement’s reflective properties mitigate heat absorption, making it an eco-friendly choice for sustainable construction practices.
  • Stain Resistance: Its non-porous surface repels stains and contaminants, facilitating easy maintenance and longevity.

Manufacturing of White Portland Cement

The dry process of cement manufacture manufactures  White Portland cement.

  • At first, the calcareous and argillaceous mixture is burned at a clinkering temperature.
  • After that the burned we ground the burned clinker to the specified fineness.
  • No ingredients other than gypsum, water, or both, will be added after burning.
  • Less than 1 % of air-entraining agents or surfactants can be added. Because less than 1 %, they have no negative influence on whiteness.

The manufacturing process of white Portland cement is almost the same as ordinary Portland cement.

  • The raw materials required are high-purity limestone (96% of calcium carbonate and less than 0.07% of iron oxide). The China clay (iron content 0.72-0.8%), silica sand, fluorspar (as flux), and selenite (as retarder). Refined oil or gas is used as fuel. Coral and seashells can also be used as raw materials for white cement production.

Physical Requirement of White Cement

  1. Physical requirements of white Portland cement shall not be less than 90 percent of those specified for 33-grade ordinary Portland cement.
  2. The degree of whiteness measured in the ISI scale is a minimum of 70% (as per IS 8042:1989).
  3.  The fineness of white cement measured is a minimum of 225 m²/kg ( as per IS 8042:1989).
  4. The initial setting time is a minimum of 30 minutes and the final setting time is a maximum of 600 minutes (as per IS 8042:1989).
  5. The bulk density of white Portland cement is 110 kg / m³ and the compact density is 3150 kg / m³.
  6. The maximum soundness of white Portland cement by Le – Chatlier’s is 10mm. The maximum soundness of white cement by Autoclave is 0.8%.
  7. For determining the compressive strength of white cement at least three mortar cubes of 50 sq. cm are prepared. The mortars are composed of 1 part of cement and 3 parts of sand(conforming IS 650:1966) by mass.
  8. The water percentage is (P+3.0)% by the combined mass of sand and cement.
  9. The compressive strength achieved (as per IS 8042:1989) thus is-
    (a) in 3 days not less than 14.4 MPa.
    (b) in 7 days not less than 19.8 MPa.
    (c) in 28 days not less than 29.7 MPa.
  10. Retention of 63-micron sieve is 1.00% maximum ( as per IS 8042:1989).

Chemical Requirement of White Cement

1. The ratio of the percentage of lime (by mass) to percentages of alumina, silica, and iron oxide is not more than 1.02 and not less than 0.66.
2. The ratio of the percentage of iron oxide, (by mass) is not more than 1.0.
3. Insoluble residue percent (by mass) is not more than 2 %.
4. Magnesia, percent (by mass) is not more than 6 %
5. Total sulfur content calculated as sulphuric anhydride (percent by mass) is not more than 2.75 and 3.0 when tricalcium aluminate percent by mass is 7 or less and greater than 7 respectively.
6. Total loss on ignition is not more than 5%.
The tri-calcium aluminate content is calculated by the formula:
Tricalcium aluminate = 2.65(Alumina)-1.69 (iron oxide).

Uses of White Cement

1. White cement markings are used to mark highway medians to increase the average visibility of the highway.
2. Due to its whiteness, white cement is used for interior and exterior decoration.
3. White Portland cement is generally used before applying paint for covering the irregularities in walls.
4. Mixed white cement with color pigments can provide a beautiful color combination while maintaining the strength of the structure.
5. White cement is used to fill the gaps in ceramic tiles, glass tiles, and marble floors.
6. After installing the ceramic bathroom fixture and the floor, white cement is used as a sealant to fill the gap.

Advantages of White Portland Cement

1. White Portland Cement is a better thermal insulator than other types of cement.
2. White cement has a good light reflector property. Hence, it saves energy by enlightening the interior and exterior of the building.
3. It can be used instead of lime or white paint or other whitewash material.
4. White cement concrete structures are the highest temperature-resisting structures.
5. White Portland cement can be used as a wall putty for filling the uneven surface of the wall before painting.

Disadvantages of White Portland Cement

1. The cost of White Portland Cement is almost four times that of ordinary Portland cement.
2. The strength of white cement is 90% that of OPC and PPC.

White cement ingredients

The exact proportions used in white cement ingredients production can vary depending on the specific manufacturer and product. However, generally, the following are the approximate proportions of the key ingredients used in the production of white cement:

Pure limestone: 80-85%
Kaolin: 10-15%
Bauxite: 2-4%
Gypsum: 0.5-1%

Do’s and Don’ts

Do’s:

  • Do Blend with Pigments: Experiment with a myriad of pigments to achieve custom colors, expanding your design possibilities.

  • Do Prioritize Precision: White Portland Cement demands precision in mixing and application. Follow manufacturer guidelines for optimal results.

  • Do Consider Lighting: Understand how different lighting conditions can affect the appearance of White Portland Cement. Test in various settings before finalizing your design.

Don’ts:

  • Don’t Compromise on Quality: Choose a reputable supplier to ensure the purity and quality of White Portland Cement, avoiding impurities that may affect the final look.

  • Don’t Rush the Curing Process: Patience is key. Allow ample time for the curing process to ensure the cement reaches its full strength and aesthetic potential.

  • Don’t Neglect Surface Preparation: Proper surface preparation is crucial for achieving a flawless finish. Neglecting this step can result in uneven coloring and adhesion issues.

FAQs (Frequently Asked Questions)

1. Is White Portland Cement more expensive than gray cement?

  • While typically slightly pricier due to the specialized manufacturing process, the long-term benefits justify the investment, especially in projects emphasizing aesthetics.

2. Can White Portland Cement be used interchangeably with gray cement?

  • Yes, it can replace gray cement in most applications, offering superior aesthetics and design flexibility.

3. Is White Portland Cement suitable for exterior applications?

  • Absolutely, its durability and weather resistance make it an excellent choice for both interior and exterior projects.

4. How does White Portland Cement compare to other white building materials?

  • Unlike paints or coatings, White Portland Cement offers inherent strength and durability, ensuring lasting performance and beauty.

5. Can White Portland Cement be colored?

  • Yes, it can be tinted to achieve a wide range of colors, offering endless design possibilities.

6. Is it suitable for DIY projects?

  • While DIY enthusiasts can work with White Portland Cement, professional installation is recommended for optimal results, especially in large-scale projects.

7. Does White Portland Cement require special curing procedures?

  • Standard curing practices apply, although precautions should be taken to prevent surface discoloration during the initial stages of curing.

8. Can it be used in underwater applications?

  • Yes, White Portland Cement demonstrates excellent hydraulic properties, making it suitable for underwater construction projects.

9. Does it require special handling or storage considerations?

  • While White Portland Cement shares similar handling requirements with gray cement, precautions should be taken to avoid contamination and preserve its pristine appearance.

10. Is White Portland Cement eco-friendly?

  • With its reflective properties reducing the urban heat island effect and its durability minimizing the need for frequent replacements, White Portland Cement aligns with sustainable construction practices.

Conclusion

In conclusion, White Portland Cement stands as a beacon of innovation and excellence in the realm of construction materials. Its unparalleled purity, strength, and versatility make it a superior choice for architects, designers, and builders alike. Whether adorning iconic landmarks or enhancing everyday spaces, White Portland Cement shines as a testament to the boundless possibilities of modern construction.

Ananta has more than 10 years of experience as a lecturer in civil engineering & a BIM Implementation Specialist.