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Of utmost importance, so, is the quality of crash barriers. There are three types of barriers: Rigid, Flexible and Semi-rigid. ?In the rigid type, if the vehicle hits the barrier, there will be extensive damage to the vehicle but nothing will happen to the barrier,? says Subramaniam. ?They prove dangerous to people though they minimise maintenance.? In the flexible ones, the vehicle hits, turns but does not go to the other side as it is turned back by the barrier. Such barriers are too flexible and you need more working width. Then, there is the throwback effect here ? when the vehicle hits the barrier, it is thrown back onto the carriageway and could cause multiple collisions. Both are two extremes ? one, very rigid and the other, very flexible. ?So, the best option is the semi-rigid crash tested barriers ? they are neither very rigid, nor very flexible. The performance of these barriers is judged by their adherence to three major factors in addition to the major duty of restraining the vehicle from vaulting over to the other side:
? The ASI (Accident Severity Index) ? the impact on the occupants of the vehicle upon collision of the vehicle with the barriers.
? The Exit Box ? The exit position of the vehicle after the collision. This is crucial as the vehicle should not impede the traffic moving on the same side of the carriageway. No driver would want the vehicle to return to the centre after an impact, so the exit position of the vehicle should be as close to the barriers as possible after impact.
? The Working Width ? The area the barriers need to work on impact. This is location defined and is completely dependent on the area available behind the barriers for the barrier to perform. In practice, Rigid barriers need no or minimum working width, Flexible barriers maximum working width and semi-rigid barriers optimum working width.
These aspects are all very well defined in the barriers that conform to European standards EN 1317. Our barriers are tested as per these standards and we have been suggesting for these on the Mumbai-Pune Expressway. The present untested barriers must be replaced as much for their quality as for their type?.
Adds Subramaniam, ?India does not have any norms on crash testing or performance of barriers, only drawings on paper are followed for the conventional barriers. So there is no performance parameter involved here. Maharashtra State Road Development Corporation (MSRDC) is using semi-rigid barriers on Mumbai-Pune Expressway but not performance barriers unlike in Europe and advanced countries where they have completely crash tested barriers. The crash barrier is basically supposed to prevent the vehicle from vaulting over the barrier but the barriers on the Mumbai-Pune Expressway fail to do so.?
Drunken driving is one challenge facing MSRDC in the face as is callous driving at night. The rate of accidents on the expressway is rather high and recently, owing to a huge public outcry over high fatalities due to cross over accidents, MSRDC decided to take some quick action. As a result, The Brifen Wire Rope Barrier of Hill & Smith Infrastructure Products India Pvt Ltd was installed and commissioned on the Expressway on April 8, 2013. These fences, installed on road Chainage (73 to 75.612) and covering a distance of 2.612km, promise to bring some relief on Mumbai-Pune Expressway. The patented Brifen Wire Rope Safety Fences are high tension cable barriers approved to NCHRP 350 TL3 and TL 4 standards. The Brifen system is the first four rope system, crash worthy end anchor, and the first system to be tested and approved by US Federal Highway. These barriers are used on dual carriageways, medians and verges. According to the company, the system comprises ?wire ropes and steel posts deployed in an arrangement that enables impacting vehicles to smoothly decelerate and be redirected with minimal damage?.
Brifen Wire Rope Barrier is a flexible barrier and has a proven track record in over 30 countries where the system has been installed and used. It has a very good track record of performing and saves human life. The injury to the occupants and the vehicle is minimised. It is fully crash tested to EN 1317 and NCHRP 350 test standards and is a CE certified product. Brifen Wire Rope Barrier is accredited by Indian Roads Congress (IRC), the standards making body of Ministry of Road Transport and Highways, Government of India. The IRC is currently working on the CODE of the wire rope barrier and should notify the same shortly. This would then help road developers and contractors to widely use the wire rope barrier in their projects to improve the road safety.
?Since there were no barriers installed at many places and since the installed metal crash barriers did not perform as the vehicles would go through the barriers and impact the vehicles coming from the opposite direction, a need was felt to install the Brifen Rope Barriers,? says V Eshwaran, Director, Hill & Smith Infrastructure Products India Pvt Ltd (HS IPI).
The Brifen system ?protects vehicles from crossing one carriageway to other (where vehicles ply from the opposite side) when their drivers veer off track and lose control of the vehicle, either due to rash driving or dozing. Since the installation of the Brifen barriers, many accidents have been reported and one major accident was reported at the same site where a high speed SUV had hit the fence. The fence prevented it from crossing over to the opposite side and there was no damage to the occupant of the vehicle,? claims Eshwaran.
Datar is of the opinion that the situation on Mumbai-Pune Expressway is entirely different from Mumbai-Goa highway. ?It has high and uneven traffic and with buses, trucks, tempos and cars, it cannot be said to be homogeneous traffic. Since there is no balance in the type of traffic, the speed of various vehicles differs. Drivers do not follow lane discipline, and speed control is not enforced. Bad driving habits contribute too and at night, alcohol, sleepiness and over speeding are the culprits?. Emphasising strongly on speed limit, he adds, ?It is extremely important for drivers to follow lane discipline even if there are fewer vehicles on the Expressway. Gimmicks and gadgets will not do much here, controlled and careful driving will. The road is good and well maintained though.?
The problem on Mumbai-Pune Expressway is that autos, two wheelers and jaywalkers can compete for speed with heavy trucks, slow containers, speeding cars and crawling tempos. Quite often, cars are parked on its side and families can be seen sharing snacks and some people can be seen relieving themselves on the road edges. The Expressway, which is supposed to be access-controlled, seems to be losing its place of pride as the country?s infrastructure marvel in transport. It was, in fact, supposed to be India?s answer to Europe?s highways but its fall from pride has been a continuous process. Anybody can walk on to the Expressway ?to take a stroll?, and there have been incidents of people stopping vehicles and looting the passengers, even assaulting them.
