Ahmedabad, Gujarat, India | National Highway Authority of India (NHAI)
The Ahmedabad Dholera Expressway (NH 751) is a transformative infrastructure project designed to improve connectivity between Ahmedabad and Dholera Special Investment Region (SIR) in Gujarat. The expressway spans 109 km and is part of a major development initiative to enhance road infrastructure in the region. It consists of a four-lane access-controlled road, connecting key locations like the Sardar Patel Ring Road near Sarkhej to the Dholera International Airport at Navagam.
Pavement stabilization plays a crucial role in the successful construction of this expressway due to the dynamic loading conditions and environmental factors that affect the road structure’s performance. With increasing traffic loads and variations in environmental conditions, traditional road pavement systems may face durability and stability issues, leading to high maintenance costs. The conventional design approaches necessitate the use of large quantities of aggregates and cementitious materials, making the pavement construction both expensive and environmentally unsustainable.
To optimize the pavement crust and address environmental and cost concerns, the incorporation of TechFab’s Techgrid Biaxial Geogrid (TGB 80) offers a sustainable and efficient solution. By reinforcing the granular layers – namely the GSB and WMM – with high-strength biaxial geogrids, the design eliminates the need for the carbon-intensive CTSB layer. This not only reduces the carbon footprint but also results in significant cost savings.
The TGB 80 geogrid, with an ultimate tensile strength of 80 kN/m in both directions, ensures enhanced lateral restraint, improved bearing capacity, and the tensioned membrane effect. These mechanisms optimize the modulus of the granular layers, improving stress distribution and reducing subgrade strain. The adoption of this geogrid reinforcement aligns with IRC SP 59:2019 and IRC 37:2018, which recommend the Layered Coefficient Reduction (LCR) method to enhance resilient modulus for GSB and WMM.
The proposed solution includes two layers of geogrid reinforcement for HS 2 and HS 3 stretches, and a single layer for HS 1 stretch. This configuration ensures optimal pavement performance while minimizing material usage. By integrating this innovative approach, the pavement design meets project requirements with enhanced durability, reduced material consumption, and a smaller environmental footprint, exemplifying a forward-thinking approach to sustainable infrastructure.
The project was successfully completed, achieving its intended purpose with innovative geosynthetic solutions. It ensured stability, reduced maintenance, and earned full satisfaction from the client and contractor. The incorporation of TechGrid Biaxial Geogrid significantly enhanced pavement performance, minimized material usage, and contributed to a sustainable, cost-effective infrastructure solution.
