The "sustainable” Pavement Management System for roads and highways made in Italy
Siteco product line dedicated to the pavement analysis is the natural consequence of the company experience in survey technologies and production of road assets and inventories, a great competence matured in over 10 years and with more than 40,000 km of surveys.
The Mobile Mapping System Road-Scanner has been expressly integrated with new equipment focused on the inspection on the state of repair of the pavement while the PMS-SIT application has been completely reorganized to allow an effective management of the activities on the road asset. The most interesting innovative factor of the solution consists in the integration in the ESRI ArcGIS system, which allows a complete control of all data collection and maintenance activities in their mapping context. Thanks to this, it is possible to have a view of the infrastructure as a whole and consult easily and quickly the state of repair and the interventions planned and carried out. Thanks to special functions for programming the maintenance interventions, the user can efficiently optimize the operating costs and get an objective assessment of the quality of the improvements achievable for the pavement.
The solution proposed by Siteco includes:
- The sophisticated technology of Mobile Mapping System Road-Scanner, which can perform measurements even in low or no light such as in tunnels.
- The PMS-SIT application, fully integrated with the powerful ESRI ArcGIS mapping system, that provides monitoring and decision support features for the analysis of Maintenance Programs related to Status Indicators.
- Supplementary surveys concerning the longitudinal and transversal roughness, friction, load capacity and/or core sampling in case of highways or when requested because of the particular conditions of the infrastructure.
Methodology has been developed with the fundamental contribution of the University of Bologna - DICAM (Department of Civil, Environmental and Materials Engineering). The following are the key phases of the process.
Definition of a complete surface defect catalog
All defects of the road pavement have been previously classified according to the catalog defined by the ASTM D6433/2003 specifications. Each defect is represented with the measurement parameter and the geometric characteristics that determine its severity.
Complete defect mapping by means of the high-performance MMS technique
The dimension parameters and the sensor necessary for the survey and the measurement have been defined for each type of defect. A specific application overlaps the visual data collected with the survey onto the data generated with the other sensors as the laser scanner point clouds. All geometries of the defects are geo-referenced and it is possible to execute measurements of coordinates, lengths and areas on them. All data are stored in a geographic database and can be viewed and tested in a GIS environment and overlapped onto the imageries.
Calculation of indicators of the maintenance status
Besides the IRI index surveyed with the profilometer, other status indicators, in compliance with the main international standards, have been identified. A special attention has been devoted to the Pavement Condition Index that is recognized also at national level. Suitable calculation algorithms process automatically, starting from the defect database, the PCI value for areas of road with constant length, in order to provide a synthetic data on the maintenance status. The index is then used to provide synthesis reports for the whole road asset or the single road.
Rendering of the maintenance status and reports for supporting decisions
The PMS renders the synthetic status indexes within a GIS environment and displays the defects per chainage, organizing them by type. It is possible to insert representations derived from external sources, such as historical data of the interventions carried out, traffic data and also meteorology data.
Definition of a database of maintenance interventions
All interventions that can be carried out on a road asset have been collected in a catalog and split into two main categories:
- General or rehabilitation interventions at different levels of depth, suitable to solve surface, or structural defects (e.g. reinforcement, partial reconstruction, rehabilitation).
- Specific interventions, defined to restore the surface characteristics and the functionality of the road surface in presence of defects such as pothole filling, patches, cracking sealing, thin overlay.
The catalog is customizable, and therefore it is possible to insert the interventions according to the customer's needs and work habits.
Association of the road maintenance interventions with the road asset
Each intervention is associated with the corresponding road section by means of GIS tools or by indicating the chainage. The choice of which intervention must be performed is left to the designer who can run fast simulations on different areas or with different types of interventions, in order to obtain a simulation with an evaluation of costs. Vice versa, if the designer first selects the defects that must be solved with priority, the application processes the optimal interventions from a technical point of view.
Evaluation of maintenance costs and simulations of PCI recalculation
The system processes the calculation of the road surfaces or of the detail of the defects for the selected routes. Since each intervention is associated with a unit cost, the system calculates the cost of the intervention or of a set of interventions, grouped into programs. On the basis of the intervention selected, the system recalculates the value of the status index. Thanks to this simulation, the optimal choice is based both on the economic element and on the technical improvement of the state of maintenance.
Regular monitoring and updating of the defect database
The pavement defects can be monitored also with other types of tools: video systems suitable to standard cars or "mobile" systems for precise checks of delimited areas.
PMS-SIT consists of 3 modules:
- Analysis of Defects: It includes, within the GIS-editor, the features for the visualization and management of the survey data obtained with the MMS Road-Scanner or from external sources.
- Maintenance Management: It allows the definition of intervention catalogs and their organization in maintenance plans; it also calculates the cost of each intervention or the total cost of each plan.
- Decision Support: It is specifically dedicated to the production of statistical synthesis reports using the data collected in the database of defects, to the calculation of the Status Index and the simulation of different maintenance strategies.