Gravel road management system and data collection

The gravel road network forms a part of the road assets managed by the Finnish Road Administration. Its management consists of data collection and storage, analysis of budget needs and selection of maintenance sections. All road assets should be able to be handled and analysed using common methods and principles, while taking into account the special features and requirements of different assets. Gravel road management has been developed from this basis by specifying the standardised classification of gravel roads, by developing key figures for management by objectives, by defining methods for funding needs assessment and selection of maintenance sections and by describing the data needs. These uses of information have then created the needs and definitions for surveys. The following key figures have been defined for gravel road management: (a) the spring thaw weakening index (KRI) is calculated as a function of the length of the weakened section, the severity of and the maintenance need caused by spring thaw weakening. (b) by using the drainage defect index (KPI) the defects of the functionality of drainage system can be described. KPI is calculated as function of defects in side ditches, culverts (including culverts in junctions) and outlet ditches,(c) the standardised classification for gravel road assets (YKL) is calculated based on the spring thaw weakening index, drainage defect index and the significance of the road. In the absence of standardised significance ranking, traffic volume weighted by the heavy traffic volume is used,and (d) the gravel road defect index (SVS) describes the condition and functionality of the gravel roads. It is calculated by weighing the spring thaw weakening index and the drainage defect index so that a sustainable maintenance policy is reached. These key figures are utilised in the funding needs assessments and also in the selection of maintenance sections. In the funding needs assessment, the proper level of maintenance budgets is defined, and the effects of various budget scenarios on condition are analysed. For funding needs assessments, a method based on the costs and the effects on condition of maintenance works has been developed, where the road network condition is depicted using the standardised condition classification. A method has been described for prioritising maintenance works for repairing defects due to spring thaw weakening and inadequate drainage. The data collection can mainly be carried on as before. The guidelines for spring thaw weakening survey should be revised so that the weakened sections are found even more effectively than currently is the case. Greater needs for change are with the survey of drainage defects. A national survey should be carried out and the current guidelines be revised. It is recommended that, instead of registering single defects, a drainage improvement plan is made for each road section and this data is utilised in the calculation of indices and selection of sections. The centralised data systems of the Finnish Road Administration are recommended for the data management: Road Register and the PMSPro. These are to be further developed so as to accommodate the management of data on section properties, maintenance works and condition (road register) and the selection of sections (PMSPro). For the funding needs assessments, a calculation methodology has to be defined. Alternatively, the analyses can be outsourced as a data service. This report may be found at http://alk.tiehallinto.fi/julkaisut/pdf/3201033-v-voh_sorateiden_yllapito.pdf