Pavement technology for rural, city roads and highways

In our country the mindset of the people, even the scientific community needs to be changed.

In earlier days because of economically cheaper to concrete ,easy to built bituminous roads were popular in our country. But we now realise that though it is cheaper to make bituminous roads it is very costly to maintain them. The escalating cost of bitumen the bituminous road cost is increasing every year. It is observed that because of development of the admixtures it became possible to make concrete road which can open to traffic in three days. We have developed concrete technology for rural. city roads and highways

1)Rural roads

Thane unit of PMGSY (PRIME MINISTER GRAM SADAK YOGNA)   laid in Murbad, Thane District first concrete road to connect  Bhangarwadi 7KM away from main Bombay- Malcej highway

The technical details are as follows. The concrete is made using conventional equipments like 10/7 concrete mixer ,screed vibrator ,channel ,cutting machine etc.

The mix design is given below.

                             KG

Cement	250-300
Flyash	150-200
Crush sand	850
Metal  1	450
Metal 2	550
Admixture	3
water	140

The concrete cost is RS 4000/M3) The 150mm thick above concrete is laid over 150mm well  compacted GSB layer. The last three years though the vehicular traffic is only bicycle,  bikes. cars and bullock cards it is in good condition

The rural roads today the bituminous wearing course is  worn out and the surface every were is of metalled one.It can be immediately surfaced by concrete roads.

2 City roads

Thane city is the excellent example of  UTWT overlay.100-150mm thick  concrete overlay over damaged bituminous roads .The city has laid 25km of roads in city

Thane municipal corporation has laid 25km of roads  in city .They have ambitious plan of further 50km of UTWT  roads in next two three yes

The mix design  is given below

                                      KG

Cement	380-400
Flyash	150
Crush sand	850
Metal1	450
Metal2	550
Admixture	4
Water	130-140

                                 

Economic

The cost of installing TWT overlay is compared with the Polymer modified bitumen mix( PMB) or crumb rubber bitumen (CRMB) mixes considering the five year bituminous mixes renewal period.

	UTWT	PMB / CRMB	Concrete
Rate, Rs. Per square meter	2200	1575	6000
Yearly repair cost	nil	100	0
	Nil	100	0
	Nil	100	0
	Nil	100	0
Renewal layer	nil	1575	0
Total after five years	2200	3550	6000

3)High ways

Reinforced UTWT of 200mm thickness is used. The reinforcement is of steel mesh of 6mm diameter  fixed at the bottom of the road.

                      

The mix design is given below

                             KG

cement	400-420
flyash	150
Crush stone	850
Metal1	450
Metal 2	550
admixture	4
water	130

The crore  of rupees spent on maintenance of the bituminous roads can be saved by concrete roads.