Highway Research Record

VI. RESEARCH WORK DONE IN ACADEMIC INSTITUTIONS RELATED TO THESIS WORK
A. HIGHWAY PLANNING, MANAGEMENT, PERFORMANCE EVALUATION AND INSTRUMENTATION
Life-Cycle Cost Analysis for Road Infrastructure Management

Date of Start:August 2004
Indian Institute of Technology Madras (R, C)

Methodology
The steps to be followed to achieve the objectives are:
(i) Collection of data:
(a). Traffic data
(b). Benkelman Beam Deflection survey data
(c). Roughness survey data
(d). Pavement condition data

(ii) Analyse the above pavement responsive measures and identify homogeneous sections.
(iii) Rank the study stretch based on the traffic, functional and structural condition data.
(iv) Consider various overlay strategies depending on the structural and functional condition data.
(v) Predict the performance of the each alternative for the design period of 20 years by using appropriate deterioration      models.
(vi) Calculate the vehicle operating cost for the each alternative for the design period of 20 years.
(vii) Compute the life cycle cost for each alternative and chose the optimal maintenance strategy.

Findings and Conclusions
(i) AASHTO’s cumulative difference approach gives the graphical representation of homogeneous sections for the project road,     based on the pavement responsive measures like deflection, unevenness and skid resistance etc.
(ii) The PCI value of the project stretch varies 20 to 40 except km 82 to 93. Pavement sections with low PCI values require      strengthening (overlay thickness>75mm) and pavement sections with higher PCI values require resurfacing.
(iii) The structural and functional performances of various alternatives are evaluated for critical deflection values of 1.25, 1.50       and 1.75 mm using deterioration models. It is observed that every section is required one or two rehabilitation measures       during the design period of 20 years.
(iv) It is observed that the capacity of existing road is exceeds during second quarter of the design period and it warrants      augmentation by an additional lane. So, new lane design is carried out according to IRC:37-2001.
(v) Life-Cycle cost analysis was carried out by considering the construction cost, routine maintenance cost, rehabilitation cost,      vehicle operating cost and salvage value in the design period. All costs are discounted to present year while comparing      various alternatives for each section.
(vi) The vehicle operating cost may not be considered in the selection of best alternative by the road construction agency.