Cold Mix Emulsion is a mix design nased tailor made bitumen binder. The main feature of this mix design process is to identify and optimize the binder as per the aggregates available from any source in india i.e dusty aggregates, soil coated aggregates, clean aggregates, damp aggregates, pea gravel aggregates or (lime mix) aggregates.This binder exceeds IS 8887 : 2018 specification of MS and SS-2, technology and can be utilized for following applications as per recently released IRC SP: 100: 2014 Guidelines.
No heating required Cost effcient Easy and unform mixing Low temperature curing Minimum preparation time for surface repair Medium setting time High adhesive properties Stable patch Resistant to stripping by water Environment friendly Bond well with cool, damp surfaces NRRDA recommends that is case of any extra cost of convertibg existing works from Hot Mix to Cold mix technology, the same shall be allowed to be adjusted with ''savingd''. NRRDA endeavor to scale up to Green and enviornment friendly road technology needs to be harnssed by all states in the country. It suggests Zero extra cost to the state Exchequer Harnessed By all.
This work shall consist of the preparation, laying and compaction of an open graded premix surfacing of 20 mm thikness composed of small sized aggregate premixed with a cationic bitumen emulsion on a previously surface, in accordance with the requirements of these specifications to serve as a wearing course.
Materials : Binder - The binder for premix wearing course shall be catonix bitumen emulsion of medium setting graded complying with IS 8887. 2018
Aggregates: coarse aggregate nominal 13.2 mm size & 11.2 mm size
Materials Proportion: The materials shall be proportioned as per quantities given in tables: Quantities of aggreagtes for 10 sq mtr area.
| Aggregates | ||
|---|---|---|
| A) | Coarse aggregate nominal 13.2 mm, passing 22.4 mm sieve and retained on is 11.2 mm sieve | 0.18 Cu.Mtr |
| B) | Coarse aggregates nominal 13.2 mm, passing is 22.4 sieve retained on is 11.2 mm sieve | 0.09 Cu.Mtr |
| Binder (Bitumen Emulsion) | 20to 23 Kg | |
The minimum air temperature for laying shall be 10 °C
Preparation of surface : The Surface should be throughly kept clean by mechanical/hand broom, and the dust removed by compressed air.
Preparation Binder : Before opening, the cationic bitumen emulsion drums shall be rolled at a slow speed, to and fro at least 5 times, for a distance of about 10 meters, to distribute any storage sedimentation.
Tack Coat : Take Coat shall be applied over the surface preparatory to laying of the surfacing.
Preparation of Premix : Premixing of cationic bitumen emulsion and aggregates can be carried out in a suitable mixture such as cold mixing plant as per IS: 5435 (MoRTH revised) or concrete mixture or by pay loaders exceptional cases.
When using concrete mixer for preparing the premix, 0.135 cu mtr (0.09 cu mtr of 13.2 mm size and 0.045 cu mtr of 11.2 mm size) of aggregates per batch shall be used. This quantity will be for 5 sq mtr of road surface with 20 mm average thickness. The coarse aggregate of 13.2 mm size shall be places into the mixer followed by 5 to 6.5 kg of cationic bitumen emulsion and then the 11.2 mm size aggregates shall be added, followed by 5 to 6.5 kg of cationic bitumen emulsion. After the materials have been thoroughly, the mix shall be immediately transported to the laying site in suitable vehicles. Too much mixing shall be avoided.