Investigating effective maintenance policies for urban networks of residential cities by using optimum and sensitivity analyses

Abstract

Rural and urban networks have been rapidly expanding over time, so there is a rising demand for more optimum maintenance policies (MPs). The low traffic weights on the urban network of a residential city makes the appearance and density of load-associated distresses rare. This encourages the city’s transportation agency to depend on limited treatment choices and the subjective judgement of the agency’s engineers in managing maintenance and rehabilitation (M&R) activities. The engineers’ judgement reflects their extensive field experience and is usually used in this type of city rather than generating optimal computerized solutions. The present study proposes two alternative MPs that are more objective than the policy that depends on engineers’ judgement. One of the proposed alternative policies allows one M&R action along the planning horizon and the other allows multiple M&R actions. The optimum analysis showed that the preventive treatment is the optimal action for more than 50% of the network segments, which means that it plays a vital and nonnegligible role in improving the effectiveness of the M&R activities. Moreover, the sensitivity of the generated M&R plans to the initial performance of the pavement, traffic volume, and the objectives weights is investigated to determine the optimal time, suitable action, maintenance need, and optimal objective weights. The sensitivity analysis showed that varying objective weights leads to different optimal and rational solutions and the most cost-effective solution is not achieved at equal weights for objectives.