Tripura, India | National Highways & Infrastructure Development Corporation Limited (NHIDCL)
Special Accelerated Road Development Program for North East (SARDP-NE) for North Eastern Region and Sikkim is a specially designed high way development program for the North Eastern region. Ministry of Road Transport and Highways has formulated SARDP – NE for enhancing road facilities in the North-East region.
Objectives of the scheme are up-gradation of National Highways connecting State Capitals with 2 lane or 4 lane roads. Under this project NH 44 was planned to be improved to a two lane road from km 6.800 to 55.000.
There were some major challenges to achieve the objectives as the availability of aggregate for construction of pavement structure was scarce and even the available resources were of marginal quality.
The state of Agartala is one of the high rainfall area and performance of pavement majorly depends on the effective drainage of infiltered subsurface water out of the pavement layers. The detrimental effects of water in the pavement system are significant. Most of the water in a pavement section infiltrates through the pavement surface during rain events. The incorporation of open-graded, free draining base/sub base layers into the pavement section as shown provides excellent drainage. For this the requirement of good quality graded aggregate is a must, whereas the project site conditions contradict the requirements. The available aggregate was of marginal quality which needed to be stabilized to achieve desired modulus values. In the process of stabilization, it was of utmost importance to ensure proper drainage requirements.
After a careful evaluation of the project requirements and site conditions, Central Road Research Institute (CRRI) has carried out detailed analysis and approved the usage of Techdrain Drainage Composite TDC 55130 which is in accordance with the requirements of MoRTH specifications section 704. The pavement designs submitted to CRRI were reviewed using IIT Pave software and permissible strains were computed using IRC 37:2012 and the layer thicknesses were recommended as tabulated below:
As per IRC 37 Clause 7.2.2, it is required that the stabilized soil layer should retain the permeability when water is likely to enter into pavement from shoulder, median or through cracks. It was therefore recommended that Techdrain Drainage Composite which possess required permeability and facilitates the subsurface drainage shall be laid between base and sub base layers.
It was ensured that the drainage composite layer is running upto the end of the toe for sub base layer including shoulders.
Techfab India has supplied the entire quantity of TechDrain Drainage Composite within the stipulated time and meeting all the quality requirements. The road construction has been completed by KMC Constructions Ltd. and is open to traffic. The project met the desired objectives and road is functioning well
