6 th PAN-HELLENIC ROAD SAFETY CONFERENCE ATHENS 12 th -13 th March 2015

Transcription

1 6 th PAN-HELLENIC ROAD SAFETY CONFERENCE ATHENS 12 th -13 th March 2015 PAVEMENT EVALUATION AND ROAD ASSET MANAGEMENT FOR IMPROVING THE ROAD SAFETY Author: Gianfranco Battiato* 1. ABSTRACT 2. INTRODUCTION 3. PAVEMENT EVALUATION AND MANAGEMENT Keywords: - Pavement Evaluation - Pavement Management - Road Asset Evaluation - Laser Profilometer - Pavement Condition Index - Skid Resistance 4. ROAD ASSET EVALUATION AND MANAGEMENT 5. CONCLUSIONS 6. REFERENCES *Dr. Gianfranco Battiato, President RODECO Group

2 1. ABSTRACT The Road Pavement and Asset Evaluation is an essential step to know and consequently to eliminate the poor road pavement conditions, mainly associated to photoles, univeness, skid resistance, as well the inadequate road signalization and other parameters, which have been proved to be an important cause of road accidents. To this purpose the Pavement Management System (PMS) and the Road Asset Management System (RAM) developed by RODECO Group are descripted in the paper. 2. INTRODUCTION The knowledge of the functional and structural parameters of the road pavements (Pavement Evaluation) is necessary to plan the maintenance and rehabilitation activities (Pavement Management) and to eliminate some important causes of road accidents, which are connected to some pavement parameters as skid resistance and unevenness. Some recent statistics in Italy attribute a high percentage culpability of road accidents to the poor road maintenance and inadequate road signalizations (1). The Road Asset Evaluation and Management is the key process to know the exact inventory and quality of the Road Asset and to eliminate the critical events and situations that may reduce the road safety. RODECO Group has developed a Pavement Management System (PMS) and a Road Asset Management (RAM) which have been continuously improved in the last years and are described in the paper. The purpose of PMS and RAM is to increase the quality of the Road Infrastructures in the short, medium and long term, for improving durability and safety, within the available financial resources, not always adequate to the requirements. 3. PAVEMENT EVALUATION AND MANAGEMENT The evaluation of pavement surface and structural characteristics of a road network is necessary in order to know the quality of the road infrastructure and to plan the optimal Page 2 of 16

3 maintenance and rehabilitation measures within a Pavement Management System, maximizing available resources, that are not always adequate to the needs. The survey of functional and structural characteristics of the pavements, done by the use of high-performance systems, is the basis of PMS. RO.MA. (Road Management) is the PMS developed by RODECO Group (2). The most important parameters used by RO.MA. are the bearing capacity (measured with FWD), roughness IRI (International Roughness Index), pavement planimetry, surface distress (PCI-Pavement Condition Index) and skid resistance. RODECO Group has developed new technologies for automatic measurement of the PCI, IRI and grip, in particular the system ADE (Automated Distress Evaluation), which allow more extensive and widespread use of high-performance systems for surveying and quality control of road infrastructures. The application of RO.MA. PMS has specifically highlighted as an efficient system of PMS can optimize the maintenance on a multiannual basis, substantially reducing the overall cost of management of road infrastructure and eliminating the critical conditions of the pavement that may affect the road safety. Particular attention was dedicated in software development, simplification and flexibility of data entry procedures, in order to reduce the amount of information necessary to obtain the results of the PMS. The main results of RO.MA. are as follows: - provide a methodology to assess the pavement conditions (surface and structural parameters) using the definition of the Pavement Quality Index (PQI); - provide a device to define an optimum plan of maintenance (scheduled maintenance) of a road, with a priority list of interventions; - estimate the optimal time to proceed to maintenance using appropriate models and predict paving future conditions and structural surface; - propose planned maintenance based on optimizing the cost / benefit ratio, with any budget constraints introduced by the user; - identify and eliminate the critical points on the road network that may reduce the road safety. RO.MA. PMS software was designed to process data coming from the analysis of the results of the Pavement Evaluation phases (field tests). For the evaluation of structural and surface characteristics of a road pavement network, there are different types of highperformance systems, which allow to quickly record all the parameters required for a proper evaluation of the PMS. The typical pavement surveys are the following: - definition of the pavement bearing capacity with FWD (Falling Weight Deflectometer); - survey of longitudinal and transverse profiles using Laser Profilometer; - measurement of pavement surface conditions and evaluation of PCI (Pavement Condition Index); - investigations with GPR (Ground Penetrating Radar) to define the pavement stratigraphy; - survey of the skid resistance. 3.1 FWD (Falling Weight Deflectometer) The structural characteristics of a road pavement network are analyzed using the Falling Weight deflectometer (FWD), which can adequately simulate the load conditions of a heavy vehicle (3). For each HWD measuring point, through the software RO.ME. (Road Moduli Evaluation, developed by RODECO), are estimated: Page 3 of 16

4 - the values of the E1, E2, E3 moduli (asphalt layers, subbase and subgrade) under test conditions; - the value of the E1 modulus (asphalt layer), referred to 20 C; - residual fatigue life of the pavement in years; - the critical layer; - the calculated theoretical reinforcement necessary to support the project traffic, in mm. 3.2 Laser Profilometer The Laser Profilometer is used for the survey of the pavement roughness, longitudinal and transverse profiles and the definition of the index IRI (International Roughness Index), measured in mm/m. The IRI is a standardized index that contains the information required to establish the regularity of a pavement surface, as defined by the World Bank Technical Paper No. 45. The irregularities of a pavement are the result of an infinite number of wavelengths, that make up the longitudinal profile of a pavement. The profilometer can detect the actual profile of the pavement in the XY coordinates (relative), where X is the distance measured by the odometer and Y represents the planimetric and elevation profile of the runway. Generally, the system is capable of storing the actual average profile every 100/200 mm of each section. The knowledge of the amplitude to short-waves (1-3.3 m), medium (3.3 m - 13 m) and long (13 m - 60 m) is very important to identify the cause of the irregularities. Where the irregularity is related to the short wave, the problem can be found in the surface layers of the pavement (surface distresses), while the irregularities related to the long and medium wave may be due to problems of subsidence in the bottom layers. The software allows, through simulation, to analyze the filtered results to obtain the values of irregularities at the wavelengths desired. Starting from the current profile, the following parameters are estimated for sections of 25 m: - IRI (International Roughness Index) averaged in mm/m on 25 m sections; - irregularities filtered to short waves from 1 to 3.3 m, in mm/m, on sections of 25 m; - irregularities filtered to medium waves from 3.3 to 13 m, in mm/m, on sections of 25 m; - irregularities filtered to long waves from 13 to 60 m, in mm/m, on sections of 25 m; - simulation of a 3 m straightedge for calculating the maximum deflection; - cross slope (%). The equipment of RODECO Laser Equipment includes: various lasers, for a width of about 3 meters, with a sampling frequency each 5 mm; - n. 3 accelerometers and n. 2 high-precision gyroscopes; - software for raw data processing, to calculate cross-slope, rutting, longitudinal profiles (IRI) and irregularities for short, medium and long waves. 3.3 Survey Distress: PCI (Pavement Condition Index) analysis The survey of the surface distress for road pavements is necessary to: - control of surface degradations and their evolution over time; - identify degraded areas to plan emergency actions; - eliminate local points of risk (as potholes) for the road safety; - provide preventive maintenance and rehabilitation to reduce or halt the process of degradation and prolong the service life of the pavements. Page 4 of 16

5 RODECO Group has developed advanced technologies for the automatic detection of surface distress as the ADE (Automated Distress Evaluation). Digital images, using VIDEOCAR system, are acquired each 4 meters, on all road pavements and simultaneously 6 different types of surface distress (classification using 3 level of severity) are detected each 25 m section (ASTM-D ). The main surface distresses that ADE system can process are the following: - longitudinal cracks; - transverse cracks; - alligator cracking; - potholes; - raveling; - depressions. Each type of surface distress should be evaluated by using 2 indices: - quantity index: % of the area needing repair; - quality index: L (low) = low severity - M (medium) = Moderate severity - H (high) = high severity. The images of the pavement, as detected by the ADE system, are post-processed with a specific software called "Automated Distress Evaluation", through it s possible to recognize and codify, on a database, the different types of distresses, in a completely automatic way. The system has a license that represents a technological innovation: Patent n. MI2008A (26/02/2008). From ADE surveys, PCI (Pavement Condition Index) are calculated for each sample unit, in accordance with the ASTM-D Starting from Videocar survey, global quantity of possible preventive maintenance/rehabilitation is defined, together with needs and priorities of maintenance, like crack sealing or other type of preventive treatments. The PCI is a numerical index, ranging from 0 for a failed pavement to 100 for a pavement in perfect condition. PCI is divided into three classes: - 70 PCI < 100 good; - 55 < PCI < 70 fair; - PCI 55 poor. Using this classification, a detailed map of all road pavements is realized, that permits to identify promptly the critical sample unit. 3.4 Ground Penetrating Radar (GPR) Surveys Through the use of GPR technology, it is possible to continuously detect the pavement stratigraphy and estimate the thickness of the different layers. The output of this survey consists of numerical tables and/or graphics that provide the thickness of the different layers of the existing road pavements. The data obtained from the GPR surveys are used to process the HWD data, to estimate the elastic moduli of different layers, and for the PMS drawing. RODECO Group has a radar system, that may mount up to 3 antennas operating between 200 MHz and 2 GHz, and that can investigate the road structure up to 3 m of depth. The antennas are installed on a vehicle properly equipped with the control unit, a computer process, a high-resolution color video and an encoder. The collected data can be displayed on screen in real time and then processed to produce tables and graphs. Page 5 of 16

6 GPR is designed to make measurements of the thickness of the pavement in accordance with the ASTM Standard D Skid resistance The skid data collection is very important to assess the adequacy of the traffic safety level and to improve the road safety. In addition to the traditional static methods to evaluate the friction coefficient, such as the british pendulum friction tester, there are high-performance systems that can measure the friction by a moving vehicle properly equipped. With these measurement systems, skid resistance can be detected almost continuously, every 1, 5, 10 meter of pavement length. The GripTester, widely used on Airports, which can be used also on road pavements, is a very simple device, consisting of a trailer towed to a vehicle; the trailer has two side wheels and a central wheel, braked during movement, used to measure the friction coefficient. Micro GripTester GripTester Scrim The braked wheel is constantly sprinkled with water by a distributor during the tests; water comes from a tank installed on the driving vehicle. The water flow is regulated with an electronic pump to ensure the desired thickness (eg. 1 mm of water) between the tire and pavement; this water thickness don t depend of the speed measurement. During the trailer movement, two longitudinal strain gauges measure the strain "Fo" (which is opposed to the travel) and the vertical load "Fv", given by the weight of the trailer; "Fv/Fo" ratio is the Grip Number (GN). The strain gauges are connected to an electronic system that records data value of the friction coefficient on a onboard computer. Measurements can be performed at different speeds. SCRIM equipment is widely used on motorways for a fast detection of skid resistance at a speed of 60 KM/h. 3.6 Definition and evaluation of homogeneous sections One of the most important step in the interpretation and processing data is related to choice road sections with similar characteristics; an homogeneous section is characterized by having virtually constant parameters throughout its considered length. The procedure to Page 6 of 16

7 calculate the homogeneous section permits to define the pavement section having similar features: once identified, they cannot be further divided into subsections having significantly different behavior. The subdivision of a road network into homogeneous sections may be based on various parameters, whose considered are the following: - IRI; - PCI; - deflection basis parameters (D0, SCI Surface Curvature Index and BCI Base Curvature Index ); - traffic; - number of layers used for backanalysis. 3.7 Description of the RO.MA. PMS software The RO.MA. PMS software (4) (5), is a tool that can provide, in the road pavement management, the optimal maintenance and rehabilitation strategies, identified through clear and simple procedures. The software, starting from a database relating to the pavement conditions and its further division into homogeneous sections, evaluates alternative strategies in a reference period of 10 years, considering the one with the highest effectiveness/cost ratio, for each homogeneous section. The software flow chart starts from the survey data (residual life, IRI and PCI), then proceeds to the definition of homogeneous sections, with the method following described, for all considered parameters. As database was created, and enriched over the time by surveys described in the chapters before, the software works following four main steps, which will subsequently be detailed separately: - database of pavement parameters referred to the current condition of the pavement, definition of the homogenous sections and priority levels set for the road network elements; - prediction models of the IRI, PCI, and RL (Residual Life) over the time and parameter range for specific maintenance treatments; - maintenance measures and their characteristics; - calculation of the optimal strategy for each homogeneous section, considering budget constraints or free budget. 3.8 Prediction models of pavement parameters (IRI, PCI and RL) and selection of maintenance level Prediction models for IRI, PCI and RL parameters have been provided inside the software as a function of the possible traffic class of the road network. For each parameter, basing on technical experience, a decay curve was calculated for each traffic class. These models depends on time, so the value of a particular parameter can be calculated at any time during the service life of the pavement. It should be noted that these models have to be calibrated starting from the results of the high performance survey that must be repeated over the time, to create an historical pavement database. For each parameter it is necessary to identify different ranges, when a type of maintenance treatment can be used, according to the three maintenance classes: a) Preventive maintenance: required treatments that restore only the PCI parameters; b) Partial reconstruction maintenance: required measures that restore PCI, IRI and RL parameters not in a complete way; c) Rehabilitation maintenance: required treatments that restore PCI, IRI and RL parameters to the project conditions. Page 7 of 16

8 IRI IRI values High Traffic Medium Traffic Low Traffic Pavement Age (years) Prediction model for IRI parameter, depending on the traffic level Consequently, three ranges have been defined for the parameters IRI and PCI; for the RL, 4 levels of maintenance are been considered (the Do Nothing condition was added). 3.9 Types of maintenance treatment and their characteristics Within the RO.MA. PMS software, it was decided to use a set of 9 maintenance treatments, divided into the three maintenance classes (see classification above). For each treatment it was necessary to define: - the maintenance class which it is part of (preventive, partial reconstruction or rehabilitation); - what parameters are repaired and how it restores (the recovery of each parameter is expressed as a percentage of the existing value); - the unit cost (depending of the type of treatment); - the expected life for each maintenance treatment (the required time of pavement to decay in the condition before applied maintenance). Once established treatments list and their activation range, it is possible to define the treatment selection tree, the heart of the software: this tree represents the pavement situation, both before and after any maintenance, based on the calculation of PQI parameter Definition of the optimum strategy for each homogeneous section considering budget constraints or free budget Once defined maintenance treatment and their application range, the last step of the software is to identify the best possible strategy for each homogeneous section during the PMS time. Strategy refers to a plan of action that includes one or more specific maintenance operations designed to restore and improve the performance characteristics of the pavements. Starting from the current value of PQI, the software calculates the best possible maintenance strategy, by combining the various types of treatments. This calculation is performed considering the possibility that the strategies are not applied to the first year of analysis, but they are deferred over the time, allowing the decay of all parameters, following their prediction model. This approach is used because some interventions have a useful life less than the period of analysis on which the strategy is evaluated, then calculating strategies that involve the application of multiple treatments it s possible to cover the entire period analysis. The strategies are established from the decision tree starting from the set of maintenance treatments listed in the previous chapter: a strategy will therefore consist of one or more branches of the tree, depending on the duration of the proposed maintenance period. At the end of the analysis, the results, for each strategy, will be a vector having the following features: - ID code, related to the homogeneous section; Page 8 of 16

9 - maintenance treatments types included and year of application. Each section will have different maintenance strategies, because it depends when the Road Authority decide, to take action on the section. Definition of different strategies for an homogeneous section The next step is to define the effectiveness of each strategy, its cost and the effectiveness/cost ratio, in order to choose the optimal strategy for each section. In this case it s necessary to consider two possible cases: the case where there is a free budget, and if there are economic constraints 3.11 Free budget Analysis For each strategy it s necessary to identify: - his effectiveness, calculated on the PQI parameter; - total costs of maintenance treatments considered. About the calculation of the effectiveness of single-strategy (E), it will be identified graphically by the included area between the curve that represents the strategy after his application and the PQI curve before. By computing, for all possible strategies of each homogeneous section, the ratio between the effectiveness of single strategy and total cost (E/CCA), the strategy, that will have the higher value of the previous ratio, will be chosen. At the end of this process, which will be repeated for each homogeneous section, it will be possible to estimate the total budget to be invested for the implementation of the best strategies identified Limited budget Analysis The method used to identify the best strategies, when a preset budget in the time of analysis (10 years) is used, allows in addition to the definition of the best strategies to be applied to all homogeneous sections, to perform an analysis at different budget levels: inserting a different value for the estimated budget, strategies choice will change, in accordance with the most appropriate capital to invest. 4. ROAD ASSET EVALUATION AND MANAGEMENT FOR IMPROVING THE ROAD SAFETY In order to create a dynamic Road Asset Evaluation and Management process, a Mobile Mapping System and a GIS Software is necessary. The VideoCar Laser Survey designed and developed by RODECO Group, is a mobile mapping system to make a precise high resolution survey in very fast time. Page 9 of 16

10 The vehicle is equipped with many different sensors, able to perform a very high detailed survey along its trajectory. By this technology it is possible to create a geographic database to manage with the GIS software RAMSIT (Road Asset Management) developed by RODECO. The VideoCar Laser Survey system is designed for a complete road inventory and Asset Management, in order to acquire in real time and by a post processing method, several sets of data like: - vehicle route; - road size, signs, posters, lamps, pavements, sidewalks, guard-rails, tunnels, retaining walls, etc; - geo-referenced and high resolution images acquired in JPEG or AVI format. The road images are very useful for the public administration because they allow a quick and easy check of the status of the road network; - longitudinal profile and road pavement roughness (IRI International Roughness Index), cross slope; - PCI (Pavement Index Condition) automatically evaluated by ADE (Automatic Distress Evaluation) system for each pavement section taking into account the distress type (alligator cracks, logitudinal and transversal cracks, ravelling, photoles, settlements, etc.) and its severity. 4.1 Road Asset Management by GIS RAMSIT RODECO has developed a GIS software RAMSIT (Road Asset Management) to create an easy way to access and manage all roads and infrastructure maps and asset information directly from any desktop. RAMSIT is a tool that can assist with the planning and decision making process and can be used by any discipline (structural and functional pavement management, signals inventory, pipelanes maps, etc.). This application will include all aspects of road network operations and management, including asset and infrastructure data maintenance with special design assistants, query and analysis, thematic mapping, customized reports, interaction with CAD data, and imagery file information. Asset Management, Facilities Management and the GIS system contain all informations about field and facility assets including their physical location and network relationships to the road infrastructure. 4.2 Plan of Work for a Road Asset Management The work plan for the establishment of a Road Asset Management provides in general the following steps: 1) acquisition of existing digital mapping of the entire road network directly by the customer; 2) definition of the technical specifications related to the characteristics of the individual features to be detected; 3) placement of the markers, additional surveys on the ground for the definition of the milestones of beginning and end of the each road and the detection of punctual events that cannot be detected with high-performance systems; 4) relief of the road axis through Videocar (with GPS and Inerzial Measurement Unit), validation of traffic routes and Plano-altimetric analysis ; 5) pavement distress survey with "Videocar Laser System" 6) survey the features of interest involves the identification, location and geo-referencing of the element, by the relief of the progressive road chainage (automatic) and geographic WGS84 position; Page 10 of 16

11 7) upload data in the Information System RAMSIT with the road information detected and definition of the level of quality and functionality of the pavement, plan of preventive maintenance and emergency measures and planning of maintenance in the short and medium term. Videocar Laser survey System RamSit GIS for Road Asset Management 4.3 Road survey with high performing equipment (VIDEOCAR) The cartographic laboratory mobile equipment (high-performance system) used for the survey of multimedia information related to road asset is the VIDEOCAR (assembled by RODECO Group with software developed within the Group). The main advantages of using the system VIDEOCAR are: - speed of execution, the surveys will be carried out with no need to stop the traffic ; - reduction of costs; - high accuracy and reliability of the information through the level of automation; - ability to provide users, even in later times, information relating to the road layout; - return of all data on standard media ; - ability to integrate data related to cartography by CAD -GIS - collection and storage of both analog and digital images on various media; - simultaneous acquisition of position data and attribute/qualitative data; - storage in the database the Road Information System, which allows you to update and consult with specific functions. Page 11 of 16

12 Composition of the high performing survey system The new high-performance system is equipped with the following subsystems: - Integrated positioning: odometer high accuracy (tolerance less than 0.5 ); GPS with DGPS differential correction and Inertial Measurement Unit; - Platform Video capture: no. 4 digital cameras; computer calculation with professional acquisition cards; software for survey and georeferencing of images. 4.4 Specific attributes to be detected with high performance systems for a Road Asset Management The work to be done in order to proceed to the identification and cataloging of items of interest for the production of the road inventory includes the following steps: - preparing, with the assistance of the Road Department, data sheets containing all the informations that must be reported; - data adjournment retrieval and technical documentation is maintained by the customer for the items to be collected; - census (identification and classification) of the elements of interest; - positioning on the cartography of the points and connect to the database of the road cadastre; - display the images that match your queries; Example of some entities of interest that could be included in the road inventory a) ROAD PLATFORM - coordinate metric start / end, measured respect to the origin of the road; - track width for homogeneous sections; - distress: type and severity of surface distress holes settlements longitudinal and transverse cracks crocodile cracks raveling etc. - notes; - survey data. b) ROAD JUNCTIONS,ACCES ROADS - co-ordinates of the road junction, as measured by the vehicle with respect to the origin of the road; - geographic position in WGS84 coordinates; - typology; - digital image of the junction; - notes; - survey data. c) ROAD SIGNS AND MARKINGS - coordinate metrics, as measured by the vehicle relative to the origin of the road - Geographic position in WGS84 coordinates - figure - article - condition; Page 12 of 16

13 - position; - digital Image; - notes. 4.5 Software GIS RAMSIT (Road Asset Management) The software RAMSIT intends to help users in roads management, proposing an integrated platform in which the procedures of acquisition, consultation, production and maintenance of the data are carried out under the supervision of a computerized management system. In the G.I.S. " RAMSIT " are integrated Esri data - ArcView (Shape), Microstation (DGN), Autocad (DWG - DXF) and raster ( tif, jpg, gif, etc.). Designed for Windows XP/7 operating systems with architecture Stand alone or client/server in the local network, RAMSIT has a very simple user interface to permit the analysis of graphical data and / or alphanumeric even by less expert users. The software is interfaced to the most popular databases like MS Access, SQL Server. The program allows user to use an area like the graphics window in which to manage the mapping format Raster and/or Vector, photographs, images, video, and on infinite levels, all elements of interest for a complete road management. The software, through simple and immediate tools, offers the functionality to: - import and manage alphanumeric and geographic data through friendly interfaces; - view the movies of roads connected to the progressive reference and their geographical location; - generate and print graphs based on queries on the database ; - interface with mobile devices as smartphone or tablet PC; - see maps with thematic data; - perform spatial analysis; - view attributes, photographs and digital movies of the elements located on the cartography; - import files from other sources (office, CAD, etc.). Survey in PESCARA City Page 13 of 16

14 The system also allows you: Survey in REGGIO CALABRIA Provincial Roads - the management of the road network with reference to the progressive milestones or the civic number; - the management of the elements related to the road including pipeline works, road maintenance and signals; - the automatic positioning with reference to the progressive milestones or geographic position from GPS data; - the overlap of raster and vector maps ; - the management of images associated with items (photos, video, etc.); - the location and viewing movies referenced on the roads streets by continual reference to the progressive chainage. For each type of attribute a management of historical data is implemented in order to monitor the evolution over time and the effectiveness of interventions performed. 4.6 Surveillance of the road network by the platform "Mobile" RAM-PHONE for improving the road safety and updating the cadastre of the roads In the field of road safety, timeliness and quality of information plays a crucial role. The RAM-Phone solution has been created as a tool for the collection of data during the surveys or maintenance works, through the use of last generation SmartPhones. The introduction of this management tool, allows to considerably simplify and streamline all activities that require a site visit in order to analyze, verify or collect information directly on field. The application, integrated with the information system RAMSIT, allows, for each user to: - send and receive multimedia georeferenced information which can be displayed in real time in RAMSIT GIS environment; - collect new features or informations on the road network or update those already present in the database according to the standards in use by the Road Department; - continuous monitoring of the state of efficiency and security of the network and immediate transmission of information with photographic documentation; - a continuous link between office and the operators on the road. Page 14 of 16

15 Asset Management System - GIS Implementation The ROAD ASSET MANAGEMENT RAM developed by RODECO Page 15 of 16

16 5. CONCLUSIONS The quality of the road pavement and the condition of the whole asset of the road infrastructure may have a strong influence on the road safety. For example, an insufficient pavement skid resistance, associated to incorrect planimetry, as well the conditions of road marking, may contribute to increase the risk of road accidents. The surface pavement distress (potholes, unevenness, etc) is another important cause of road accidents. According to the conclusions of a research carried out by the ANEIS (the Italian Association of Experts in Road Safety ) and Italian Society of Road Infrastructures (SIIV), more than 50% of accidents in the Italian Road Network ( Kms) are linked to a poor road maintenance and inadequate road signalizations. Moreover the 50% of the road signs (12*10 6 all over the Italian road network) are out of standards and their replacement would require an investment of more than 2*10 9 Euros. In most cases the different Road Authorities even don t know the condition and the consistency of their pavements and road asset. To this purpose the development of a Pavement Management System (PMS) associated to an Asset Road Management System (RMS) can considerably improve the quality of the road infrastructure eliminating the events that may reduce the road safety. 6. REFERENCIES (1) ANEIS (Italian Association of Experts in Road Safety). - Fabio Cavagnera on 9 th December (2) Battiato, G.; Amé E.; Wagner T., Description and Implementation of RO.MA. for Urban Road and Highway Network Maintenance. In Proceedings I for Third International Conference on Managing Pavements, S.Antonio, Texas, USA, May , (3) Battiato, G.; Larsen B.K.; Ullidtz P.,1987. Verification of the analytical empirical method of Pavement Evaluation based on FWD testing. In Proceedings for 6th International Conference on Structural Design of Asphalt Pavements Ann Arbor, Michigan, USA, (4) Battiato, G.; Larsen B.K., Description and Application of RO.MA. (Road Evaluation and Pavement Management System). In Proceedings for III International Conference on Bearing Capacity of roads and airfield, Trondheim, Norway, 3-5 July (5) Battiato, G.; Al Emadi K.M.I.; Liberati P, Description and application of the Pavement Management System (PMS) developed for the State of Qatar. Proceedings for XXII Word Road Conference Durban, South Africa, October Page 16 of 16