A Review of Highway Agencies in the South Asia Region

A Review of Highway Agencies in the South Asia Region
Table A6: Computation of NQI
in millimeter (mm) per km of road. The following steps can be used to compute the NQI of
the network.
Step 1: The roughness levels may be measured all along the CRN once a year; divide the
network into the following categories:
(a) Length where roughness is up to 3,000 mm/km
(b) Length where roughness is between 3,000 and 4,000 mm/km
(c) Length where roughness is more than 4,000 mm/km
Step 2: Tabulate the results and compute the NQI considering the extent of roughness on
the network as indicated in Table A6.
Roughness Level Percent Length of CRN Relative Score Weighted Score
Up to 3,000 mm/km x 1 100 x 1 = WS 1
Between 3,000 and 4,000 mm/km x 2 80 0.80 x 2 = WS 2
More than 4,000 mm/km x 3 50 0.50 x 3 = WS 3
Network Quality Index WS 1 + WS 2 + WS 3
Table A7: Result of analysis in Step 1
Higher the value of NQI, better the performance of the highway agency.
An example to illustrate the computation of NQI follows.
(i) Let us assume that, as a result of the analysis carried out in Step 1, the following picture
emerges (Table A7):
Roughness Length Percent Length
Length where roughness is up to 3,000 mm/km 4,000 km (33.33%)
Length where roughness is between 3,000 and 4,000 mm/km 6,000 km (50.00%)
Length where roughness is more than 4,000 mm/km 2,000 km (16.67%)
Total 12,000 km 100.00
Table A8: Computation of NQI
(ii) Computation of NQI
Roughness Level Percent Length of CRN Relative Score Weighted Score
Length where roughness 33.33 100 33.33
is up to 3,000 mm/km
Length where roughness 50.00 80 0.80 x 50.00 = 40.00
is between 3,000 and
4,000 mm/km
Length where roughness is
more than 4,000 mm/km 16.67 50 0.50 x 16.67 = 8.33
Network Quality Index 81.66, say 82
84