By Strata Geosystems (India) – Several days of torrential rain in March 2016 completely destroyed a stretch of National Highway 44 (NH-44) in India. The roadway is the main throughway for commercial traffic to the State of Tripura. The failed road zone was located on the Assam side of the Assam-Tripura border. A geocell-supported road solution was specified to repair the damage quickly.
The region needed fast response. NH-44’s essential transit role meant that any impassability meant spikes in fuel and food prices.
The gecell-supported solution was able to be applied in just 15 days from beginning of the construction works to reopening of the roadway.
GEOCELL-SUPPORTED ROADWAY WORKS
The Assam Public Works Building and NH Department sought a geosynthetic solution. Strata Geosystems was able to provide expert insight into the use of geogrids and geocells in roadway rebuilds.
The subgrade of the highway section to be repaired was characterized by highly plastic, weak, clayey soils. The stretch traverses forested and undulating terrain where drainage issues and a low permeability subgrade complicated matters. Since the two major challenges were pavement drainage and subgrade strength, Strata proposed StrataWeb® geocell-supported pavement section.
The construction was direct:
- Remnants of the old, damaged road were scraped off
- The subgrade was dressed, levelled, and compacted
- A nonwoven was placed above the compacted surface to prevent intermingling of the engineered section with the weak plastic subgrade
Of note, the highway was able to be opened to traffic for all types of vehicles just after the granular base was installed. Later, bituminous concrete and dense bituminous macadam layers were placed.
The geosynthetic approach enabled the project team to use of locally available infill material, and the work was able to be completed in 15 days from the receipt of the geosynthetics on site.
Construction activities and costs were also minimized because the geocell-supported design was able to be executed without heavy equipment. The minimal equipment required were dumpers, front loaders, and compacters.
Not only did the use of the geocellular confinement panels reinforce the roadway, the perforated, high-strength walls of the geocells relieved pore water pressure in the subgrade, thus providing effective drainage from the system.
“The NH-44 at Churaibari once became infamous for mud and slush is now transforming into heaven of beauty,” noted a representative from the Assam PW (Buildings and NH) Department. “All this has been made possible by the use of geocell in road construction.”
For more information about Strata Geosystems’ geosynthetics and engineering services, from India visit www.strataindia.com.
For global Strata Systems information, visit www.geogrid.com.2