Eight lanes on Dwarka Expressway’s Basai-Delhi stretch to be on a single pillar

GURUGRAM: Package 3 of the Dwarka Expressway project, including the elevated highway on single pillar support, has started catching steam on the dividing road of Sector 109 and 110. The four laning of 400 metres and 275 metres has been completed at two separate locations — between Basai railway overbridge and Gurugram-Delhi border. And, the eight-laning of the main carriageway has been done at pillar 74 towards Delhi side.
“There are 14 segments between two pillars about 40 meters apart. The work on the middle portion is being done and the launching of the wings is also being done simultaneously. Normally, there’s a week-long cycle for the eight-laning of one span,” claimed an NHAI official.
The project contractor claimed that by month end, another set of eight-laning will be completed. Both NHAI and project contractor have asserted that due diligence is being paid on the work and minutest details are being looked into. The reason, they claim, is the fact that this is the first-of-a-kind project. While there have been few six-lane elevated roads like one in Mumbai, this is for the first time that eight-lanes are being erected on a single pillar. Thus, the project assumes more importance. The technique is said to be effective both in terms of financial investment and land resources. Also, it leaves the option of future expansion, depending on the increase in population density and load on the carriageway. “We are using only one pillar instead of two or more. So, essentially we are using half the land space. In future if more lanes are to be added it can be easily done. Moreover, it’s very cost-effective and less time-consuming. The strength factor is more or less the same. It’s just newer technologies are used in such structures. And because it’s new and different, it becomes a marvel for people, making it a cherished asset for them,” said RK Mishra, project director for package 3 (Basai to Delhi border) and 4 (Kherki Daula to Basai).
What will the eight-lane carriageway be like? The 8.5 km stretch from Basai to Delhi border will be elevated. The eight-lane carriageway will have elevated service roads as well. The entire stretch will be signal-free along with new innovative technologies like Intelligent Transportation System (ITS) that will have reflective screen displaying crucial traffic information like vehicular pressure and CCTV cameras.
In a major relief to the residents of the new sectors, the project also envisages to avoid traffic conflict point, a major issue in NH-8 and arterial roads leading to road safety hazards. For this, at few junctions there will be elevated service roads. Underpasses at key junctions like Basai, Bajghera, Gurugram-Delhi border, among others will also be created for smooth passage of vehicles.
The entire package is over 40% complete and is expected to be completed by March 2021, an official said.
Why is it unique? Innovations are being used, like elastomeric bearings imported from Malaysia. These are placed between the superstructure (carriageway) and the substructure (the pillar). “The bearings absorb load and ensure that the structure is not entirely rigid. We have many options in the market, but elastomeric bearings have proved to be most effective both financially and in terms of performance,” Mishra added.
Similarly, about 14 segments between two pillars will be held by cables using pre-stressing to provide strength to the structure. “We have used pre-stressing method for the casting of the wings. This means pre-testing of strength based on load analysis has been done. Once structure is ready post-testing will also be done to ensure it has maximum strength and the longevity it needs. Also, the segments will be held together via duct cables passing through the holes in these segments. Similar technique is used for wings too,” said Sarfaraz Hussain, L&T project manager.