Bharuch, Gujarat, India | Western Railways
Bharuch Junction is a railway station on the Western Railway network, located in Bharuch, Gujarat, India. It is part of western line between Vadodara and Mumbai. It is one of the busiest railway lines of the Indian Railways and is fully electrified. The Western line of the Mumbai Suburban Railway operates on the southern part of this route. And Chavaj is nearby location from Bharuch.
During site visit along the line, it was observed there was development of cracks on the top of formation during summer months. Minor shrinkage cracks were formed in highly shrinkable soil. If not attended on time, these enlarge which may progress to ballast layer, resulting in the settlement of the track. The situation may worsen in the rainy season when water will enter into the formation through these cracks and may cause swelling, resulting in frequent cross level variations. Formation failure comprises most of the unstable project stretches. Increase in axle load & GMT also have a significant effect on adequacy of bearing capacity of formation. Therefore, strengthening of formation against bearing capacity failure is an important rehabilitation work.
Based on the site observations and soil testing, the relevant remedial measure was formulated. Western railway authority suggested formation treatment using GeoGrid & Geotextile for 6.00 Kms project stretch.
Generally, the preferred method for strengthening/rehabilitation of weak/unstable formations is provision of a Blanket layer of suitable thickness. Due to increasing scarcity of good quality fill material, it was not feasible to adopt this method, and only shallow depth of formation is considered to be affected/weak. Alternatively, laying a separator layer of non-woven geotextile and a reinforcement layer of geogrid over it, just below the ballast in proposed typical cross section shall prevent the differential settlements if any caused by underneath weaker formations and minimize the track maintenance.
Client was satisfied with the quality of product and timely supply of material as per schedule. The technical support provided by TFI team during installation was appreciated.
Cracks were observed on the formation surface during summer months due to highly shrinkable soils. If untreated, these cracks could extend into the ballast layer, causing track settlement and cross-level variations, especially during monsoon when water infiltration leads to swelling.
The blanket layer requires large quantities of good quality fill material, which was scarce. Transporting such material would have been costly and time-consuming. Moreover, only shallow depths of formation were affected, making full blanket replacement unnecessary.
Western Railways opted for a geosynthetic-based formation treatment:
This combination was applied over a 6 km project stretch.
