Bridges and Flyovers under JNPT-NHAI project:

The National Highways Authority of India (NHAI) is an autonomous agency of the Government of India managing a network of over 50,000 km of National Highways out of 1,32,499 km in India.

Jawaharlal Nehru Port Trust (JNPT) is India’s 2nd largest container port after Mundra Port. JNPT is located at Uran taluka in the Raigad district of Maharashtra, a few miles from Navi Mumbai.

The National Highways Authority of India has undertaken the upgrading and improvement of multiple bridge and flyover projects connecting JNPT with the rest of India’s road network.

Because of damaged bridges and flyovers falling under the JNPT-NHAI project, logistics involving merchandise exports or imports suffered very much. Merchants have no choice but to use alternate modes of transport, leading to higher expenditures.

The upgradation of bridges and flyovers under the JNPT-NHAI project will decrease the travel time and the cost of vehicle operation. It will strengthen the economic development of the region owing to the growth of exports and improved connectivity with JNPT.

The bridges and flyovers under the JNPT-NHAI project, situated in Nhava-Sheva, Navi Mumbai, presented unique challenges to project engineers.

The need for structures to withstand environmental stressors, including heavy rainfall, high humidity, and extreme heat, required innovative solutions.

Contractors sought the assistance of Sunanda Global, a leading provider of construction chemicals, to supply acrylic exterior anti-carbonation coatings designed to protect against carbonation and similar environmental attacks.

Surface Preparation & Cleaning:

The success of any exterior coating application hinges on meticulous surface preparation.

In line with industry best practices, the contractors undertook a thorough cleaning process to remove dirt, loose particles, and flaking paint from the surfaces.

The inspection revealed any cracks or openings, which were duly filled with a polymer-modified mortar. On steel surfaces, the removal of scales, rust, and grease ensured a pristine foundation for the application of the aliphatic acrylic coatings.

Application Process:

Sunanda Global’s acrylic exterior coatings proved to be a versatile solution, easily applied by brush, roller, or spray.

Sunanda’s liquid coatings demonstrated excellent adhesion properties, ensuring a durable and long-lasting finish.

Contractors followed a two or three-coat application process, with a minimum interval of 4-6 hours between successive coats.

Throughout the application and curing period, precautions were taken to protect the coating from dust, dirt, and grease, ensuring the optimal performance of the exterior coating.

Advantages of Sunanda’s Anti-carbonation Coatings for Bridges and Flyovers under JNPT-NHAI project:

The application of acrylic exterior anti-carbonation coatings delivered a myriad of advantages to the bridges and flyovers under JNPT-NHAI project:

Waterproofing and Dampness Prevention:

The coatings effectively protected structures from water leakages and dampness, contributing to the overall integrity of the infrastructure.

Heat Insulation:

By preventing the rise in internal temperature, the aliphatic acrylic coatings played a crucial role in maintaining a comfortable and controlled environment within the structures.

Longevity and Durability:

The coatings exhibited remarkable resistance to peeling and cracking, ensuring a prolonged service life for the infrastructure. This not only reduces maintenance costs but also enhances the overall sustainability of the project.

Anti-Carbonation Properties:

The coatings acted as a barrier against the carbonation of concrete, mitigating potential structural damage and extending the total service life of the project.

UV Stability:

With excellent UV stability, the coatings retained their aesthetic appeal over time, even in the face of prolonged sun exposure.

Resistance to Fungi and Algae:

The coatings’ formulation prevented the formation of fungi and algae, maintaining a fresh and visually appealing exterior for years.

Abrasion Resistance:

The coatings demonstrated a good resistance to abrasion, ensuring longevity and durability even in high-traffic areas.


The application of Sunanda Global’s anti-carbonation coatings for the bridges and flyovers under the JNPT-NHAI project in Nhava-Sheva, Navi Mumbai, has redefined the standards for infrastructure resilience.

Sunanda Global’s advanced coatings have proven instrumental in protecting bridges and flyovers against environmental challenges, ensuring a robust and sustainable foundation for the future.

As the industry continues to embrace innovative solutions, the success of this project stands as a beacon, highlighting the transformative impact of cutting-edge exterior coatings in civil engineering.