brief report of the problems of Heavy Loaded Vehicles on

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A brief Report on the
problems of heavy loaded mining vehicles
on the roads constructed under PMGSY.
1.
It has been brought to the notice of Ministry of Rural Development (MoRD)/ NRRDA that
roads constructed under PMGSY are undergoing premature failures due to the incidence of
traffic with heavy loaded vehicles, particularly in the areas where mining activity is prevalent.
Such failures are reported from the states of Chattisgarh, Orissa and Jharkhand to a larger
scale and in some stray cases from other states.
2.
In the light of the above, a brief background note indicating the reasons for the heavily
loaded vehicles to come on to PMGSY roads and the influence of such vehicles on the
extent of damage on the roads was prepared to facilitate discussions at the meeting with
state representatives. The report is summarized in points 3-6 below.
3.
PMGSY aims at providing rural connectivity by a single all weather basic access. The
objective here is bringing rural habitants on to the main stream with access to socio economic services, such as health, education and marketing facilities. It may be indicated
here that the mandate in providing rural connectivity is not to cater for heavy traffic,
particularly the vehicles using for mining purposes.
4.
The rural roads constructed under PMGSY, being of higher quality with standards
specifications for rural traffic are likely to attract traffic with heavy loads in the following
circumstances.
5.
(i)
After the road is constructed, the land use in the hinterland might have been
altered, resulting in the generation of higher levels of traffic, which is likely to use
the facility created for rural connectivity.
(ii)
When the alternative routes available expected to carry heavy traffic, might have
not been kept in good condition with appropriate strengthening and
maintenance. This situation will result in diverted traffic from the normal route to
the newly constructed PMGSY roads, which otherwise are not meant for it. This
unexpected diversion with heavily loaded vehicles when allowed to ply on the
rural road definitely causes premature damage of the rural roads not designed
for carrying heavy loads.
Regarding the likely impact of such diversion, it is to be indicated here that the equivalent
damaging effect of normal vehicles will be far less compared to the heavily loaded vehicles
on the pavement. It is in order to indicate here that the damaging effect of an axle load on
the road will be in the order of the fourth power of the ratio of the axle load coming from
any vehicle to that of the standard axle weight, which is normally considered as 8 Tones.
For example the equivalent damaging effect for a vehicle with 3 tone load axle is 0.02, while
the same for a 6 tone axle is 0.29, for a 10 tone axle is 2.25 and for a 14 tone axle it
would be 8.66. This can clearly indicate the relative damage likely to occur on the pavement
due to different axle loads. The impact of over loaded vehicles on the damage of the road
can be seen clearly through the above illustration.
6.
The rural roads under PMGSY are normally designed for the rural traffic, duly considering
the normal rural traffic such as tractors, mini buses and occasional normal buses and trucks,
whose cumulative damaging effect in terms of Vehicle Damage Factor (VDF) will be in the
order of a little more than 1. However, when the heavy loaded mining trucks use the rural
roads, the Vehicle Damaging Factor may go upto of 4-6, which itself speaks about the extent
of damage it can cause and that is what is happening in the cases referred to.
7.
In order to get more details and the conditions under which failure of roads is noticed, the
representatives of the states of Chattisgarh, Jharkhand and Orissa were called for a meeting
under the Chairmanship of DG, NRRDA on 1st February, 2008. The state representatives
provided the supporting data on the failure of the roads including the assumptions made on
the expected traffic at the time of design of the roads and the current scenario of the
composition of traffic
8.
While Chattisgarh has given a list of 68 roads, Orissa has submitted the data in respect of 6
roads. The factual data from Jharkhand is awaited.
9.
During the meeting the connected issues such as the type of vehicles plying on the newly
constructed rural roads, the reasons for it such as opening new mines / quarries after the
construction of rural roads, the diversion that is taking place from alternative routes, which
were not in good condition and the shorter linkage provided by the newly constructed
PMGSY road. It has come out that irrespective of the reasons, the final outcome noticed is
the failure of the roads construed under PMGSY, calling for urgent restoration / rehabilitation/
reconstruction of the roads constructed earlier.
10.
During the deliberations, it came to light that when new mines are opened certain states
have a provision to meet the restoration costs from the revenue generated in the form of
royalties to the states on mining. The other point of view expressed was that the alternative
routes normally of higher order should be maintained and kept in good condition, in order to
avoid large scale diversion of the mining traffic on to the rural roads which are neither meant
for such traffic nor designed for. Further, it was felt that the mining industry or similar high
traffic generating units be taken as partners in the rehabilitation of PMGSY roads, since the
roads otherwise meant for rural connectivity are now catering to dedicated mining / industry
related traffic.
11.
After the deliberations, it was decided to take further action as follows:
(i)
SRRDA may prepare a detailed plan of action in respect of each road coming
under this category supported by all necessary investigations, including Axle
Load Spectrum Studies, reasons for diversion, the extent of diverted traffic and
the modified designs for restoration / reconstruction of the roads based on the
present and expected future traffic demand on the road. The three states, who
attended the meeting, have been advised to seek expert opinion for the above
purpose, if needed, and come out with the detailed action plans in respect of
each of the roads.
(ii)
Based on the analysis of the details submitted by the states, MoRD / NRRDA
and the states concerned jointly decide on the modalities and sources of
financing the rehabilitation costs of the identified roads.
(iii)
The states have been further advised to take note of such roads in progress
where there is a likelihood of incidence of diverted traffic or generation of heavy
traffic with expected change in the land use in near future. If evidence is
available, they are advised to redesign these roads under construction and
complete them with due permission from MoRD. This is required to prevent the
failure of roads soon after the construction.
(iv)
The states also have to take proactive role in sensitizing the PIUs to prepare
DPRs with more elaborate studies and precision in traffic forecasting in the
areas, where the traffic is likely to go beyond the normal expectations. Such
steps will not only prevent the premature failures, but also the inconvenience to
the rural people due to dislocation of the facility created.
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