Too often the identification of critical road sites is made by “accident-based” methods that cons... more Too often the identification of critical road sites is made by “accident-based” methods that consider the occurred accidents’ number. Nevertheless, such a procedure may encounter some difficulties when an agency does not have reliable and complete crash data at the site level (e.g., accidents contributing factors not clear or approximate accident location) or when crashes are underreported. Furthermore, relying on accident data means waiting for them to occur with the related consequences (possible deaths and injuries). A non-accident-based approach has been proposed by PIARC. This approach involves the application of the Human Factors Evaluation Tool (HFET), which is based on the principles of Human Factors (HF). The HFET can be applied to road segments by on-site inspections and provides a numerical performance measure named Human Factors Scores (HFS). This paper analyses which relationship exists between the results of the standard accident-based methods and those obtainable with...
The PRACT Project (Predicting Road ACcidents a Transferable methodology across Europe) is an ongo... more The PRACT Project (Predicting Road ACcidents a Transferable methodology across Europe) is an ongoing project aimed at developing a European accident prediction model structure that could, with proper calibration, be applied to different European road networks. The core principles behind the PRACT project structure are that: it is unrealistic to think that one unique Accident Prediction Model (APM) model with a unique set of Crash Modification Factors (CMFs) can actually be developed, valid for all Europe and for all the different type of networks; the development of a specific APM model and a set of CMFs based on local data is extremely time consuming and expensive and requires data and experience that most road administrations do not have; the development of “local” CMFs only based on historical local data prevents the possibility of evaluating the effectiveness of new technologies. The PRACT project addresses these issues by developing a practical guideline and a user friend...
A significant percentage of road fatalities and injuries occur in the nonmotorway rural road netw... more A significant percentage of road fatalities and injuries occur in the nonmotorway rural road network. One of the main causes of accidents on these roads is represented by overtaking, as, by its nature, it involves a risk of a head-on collision with oncoming traffic. The paper describes a combined simulation approach (driving simulator and traffic microsimulation) designed to examine the influence of different traffic conditions on passing manoeuvres on two-lane two-way rural roads. The main focus was the evaluation of the end of the passing manoeuvre because it reflects the risk of a head-on collision. In addition, the study aimed to assess the usefulness of the proposed combined approach in the ability to proactively and quickly diagnose traffic safety problems and consequently to evaluate appropriate solutions. The data collected with an interactive driving simulator on a sample of 54 participants have been used to adjust some input data of the traffic microsimulation software. A ...
Journal of Civil Structural Health Monitoring, 2021
One of the criteria adopted by the Word Bank with the aim of defining the economic level of a cou... more One of the criteria adopted by the Word Bank with the aim of defining the economic level of a country is represented by the condition of the road pavements. To ensure adequate road pavement quality, road authorities should be continuously monitoring and repair the detected anomalies. To fast solve problems associated with poor quality of road surface such as comfort or safety, the presence of distress must be detected quickly. The high-performance pavement distress detection, such as those base on the image processing or on the laser scanning, is very expensive and does not allow to the road administration to conduct the appropriate monitoring campaigns. To solve these problems, the paper describes the pave box methodology, an innovative and immediately operational distress detection approach based on the exploitation of data collected by the black boxes located inside the vehicles that routinely pass on the road network. Data processing and the algorithms used in the post-processin...
Every year in Italy, there are about 20,000 road accidents involving pedestrians, with a signific... more Every year in Italy, there are about 20,000 road accidents involving pedestrians, with a significant number of injuries and deaths. Out of these, about 30% occur at pedestrian crossings, where pedestrians should be protected the most. Here, we propose a new accident prediction model to improve pedestrian safety assessments that allows us to accurately identify the sites with the largest potential safety improvements and define the best treatments to be applied. The accident prediction model was developed using the ISTAT dataset, including information about the fatal and injurious crashes that occurred in Italy in a 5-year period. The model allowed us to estimate the risk level of a road section through a machine-learning approach. Gradient Boosting seems to be an appropriate tool to fit classification models for its flexibility that allows us to capture non-linear relationships that would be difficult to detect via a classical approach. The results show the ability of the model to p...
Because of potential differences between national and local conditions, the Mechanistic–Empirical... more Because of potential differences between national and local conditions, the Mechanistic–Empirical Pavement Design Guide (MEPDG) should be calibrated to a local level. Arkansas has invested heavily in efforts to implement the MEPDG. This paper summarizes the initial local calibration of flexible pavement models in the MEPDG for Arkansas. Data from the Long-Term Pavement Performance (LTPP) database and local pavement management system (PMS) were used. The solver function in Microsoft Excel was used to optimize the coefficients for alligator cracking. Iterative runs of the MEPDG by means of discrete calibration coefficients were conducted to optimize rutting models. In general, the alligator cracking and rutting models are improved by calibration. However, a question remains about the suitability of the calibrated models for routine design. Many default values were used in the MEPDG because of a lack of data. It is recommended that additional sites be established and a more robust data collection procedure be implemented for future calibration efforts. The difference in the definitions of transverse cracking between the MEPDG and the LTPP may be critical to data collection and identification. Thermal cracking should be specifically identified in a transverse cracking survey to calibrate the transverse cracking model in MEPDG. The procedure using LTPP and PMS data for local calibration of the MEPDG in Arkansas is established. Additional development of database software for data manipulation, preprocessing, and quality control—under way in Arkansas—will significantly streamline the calibration process.
The PRACT Project (Predicting Road ACcidents-a Transferable methodology across Europe) is an ongo... more The PRACT Project (Predicting Road ACcidents-a Transferable methodology across Europe) is an ongoing project aimed at developing a European accident prediction model structure that could, with proper calibration, be applied to different European road networks. The core principles behind the PRACT project structure are that: it is unrealistic to think that one unique Accident Prediction Model (APM) model with a unique set of Crash Modification Factors (CMFs) can actually be developed, valid for all Europe and for all the different type of networks; the development of a specific APM model and a set of CMFs based on local data is extremely time consuming and expensive and requires data and experience that most road administrations do not have; the development of "local" CMFs only based on historical local data prevents the possibility of evaluating the effectiveness of new technologies. The PRACT project addresses these issues by developing a practical guideline and a user friendly tool that will allow for an easier implementation of APMs and CMFs in different countries and on different road networks.
This is the SAVeRS project deliverable and not an official CEDR Publication. If and when a CEDR p... more This is the SAVeRS project deliverable and not an official CEDR Publication. If and when a CEDR publication will be issued this will be posted on the CEDR website (www.cedr.fr) and it could be an amended document as compared to this project Deliverable.
Sustainability, Eco-efficiency, and Conservation in Transportation Infrastructure Asset Management, 2014
ABSTRACT One of the most used tool for pavement design is the AASHTO Mechanistic-Empirical Paveme... more ABSTRACT One of the most used tool for pavement design is the AASHTO Mechanistic-Empirical Pavement Design Guide (M-E PDG) which is a very powerful pavement design tool but it includes empirical distress models calibrated only for conventional bituminous materials. Nowadays non conventional asphalt concrete materials as porous asphalt concrete for wearing courses, modified asphalt concrete and cement-bitumen treated materials are often used in flexible and semirigid pavements. The implementation of these materials in the M-E PDG tool requires the calibration of the distress models based on experimental data from in-service pavements or laboratory test results. In this paper the calibration of the M-E PDG Asphalt Concrete Fatigue and Asphalt Concrete Rutting models is presented for the three type of non conventional materials mentioned above. The results are presented in terms of calibration procedure, resulting calibration factors, caveats and accuracy of the calibrated functions.
ABSTRACT This paper deals with the evaluation of the interaction between a safety barrier and a v... more ABSTRACT This paper deals with the evaluation of the interaction between a safety barrier and a variable message sign (VMS) that is placed very close to the carriageways in order to reduce the length of the arm above the carriageways. The two issues addressed are the structural response of the VMS, in order to ensure that the structure will not fail under the impact of a heavy goods vehicle (HGV), and the effects of the secondary impact that occurs when the barrier or the vehicle hits the VMS structure. These issues have been analysed both in terms of overall performance of the barrier and of the resulting effects on the HGV itself. As a result, the minimum distance between the front of the barrier and the VMS support structure that will enable to have a performance fully compatible with the requirements of EN1317-2:2010 has been defined for a specific barrier/VMS system.
Too often the identification of critical road sites is made by “accident-based” methods that cons... more Too often the identification of critical road sites is made by “accident-based” methods that consider the occurred accidents’ number. Nevertheless, such a procedure may encounter some difficulties when an agency does not have reliable and complete crash data at the site level (e.g., accidents contributing factors not clear or approximate accident location) or when crashes are underreported. Furthermore, relying on accident data means waiting for them to occur with the related consequences (possible deaths and injuries). A non-accident-based approach has been proposed by PIARC. This approach involves the application of the Human Factors Evaluation Tool (HFET), which is based on the principles of Human Factors (HF). The HFET can be applied to road segments by on-site inspections and provides a numerical performance measure named Human Factors Scores (HFS). This paper analyses which relationship exists between the results of the standard accident-based methods and those obtainable with...
The PRACT Project (Predicting Road ACcidents a Transferable methodology across Europe) is an ongo... more The PRACT Project (Predicting Road ACcidents a Transferable methodology across Europe) is an ongoing project aimed at developing a European accident prediction model structure that could, with proper calibration, be applied to different European road networks. The core principles behind the PRACT project structure are that: it is unrealistic to think that one unique Accident Prediction Model (APM) model with a unique set of Crash Modification Factors (CMFs) can actually be developed, valid for all Europe and for all the different type of networks; the development of a specific APM model and a set of CMFs based on local data is extremely time consuming and expensive and requires data and experience that most road administrations do not have; the development of “local” CMFs only based on historical local data prevents the possibility of evaluating the effectiveness of new technologies. The PRACT project addresses these issues by developing a practical guideline and a user friend...
A significant percentage of road fatalities and injuries occur in the nonmotorway rural road netw... more A significant percentage of road fatalities and injuries occur in the nonmotorway rural road network. One of the main causes of accidents on these roads is represented by overtaking, as, by its nature, it involves a risk of a head-on collision with oncoming traffic. The paper describes a combined simulation approach (driving simulator and traffic microsimulation) designed to examine the influence of different traffic conditions on passing manoeuvres on two-lane two-way rural roads. The main focus was the evaluation of the end of the passing manoeuvre because it reflects the risk of a head-on collision. In addition, the study aimed to assess the usefulness of the proposed combined approach in the ability to proactively and quickly diagnose traffic safety problems and consequently to evaluate appropriate solutions. The data collected with an interactive driving simulator on a sample of 54 participants have been used to adjust some input data of the traffic microsimulation software. A ...
Journal of Civil Structural Health Monitoring, 2021
One of the criteria adopted by the Word Bank with the aim of defining the economic level of a cou... more One of the criteria adopted by the Word Bank with the aim of defining the economic level of a country is represented by the condition of the road pavements. To ensure adequate road pavement quality, road authorities should be continuously monitoring and repair the detected anomalies. To fast solve problems associated with poor quality of road surface such as comfort or safety, the presence of distress must be detected quickly. The high-performance pavement distress detection, such as those base on the image processing or on the laser scanning, is very expensive and does not allow to the road administration to conduct the appropriate monitoring campaigns. To solve these problems, the paper describes the pave box methodology, an innovative and immediately operational distress detection approach based on the exploitation of data collected by the black boxes located inside the vehicles that routinely pass on the road network. Data processing and the algorithms used in the post-processin...
Every year in Italy, there are about 20,000 road accidents involving pedestrians, with a signific... more Every year in Italy, there are about 20,000 road accidents involving pedestrians, with a significant number of injuries and deaths. Out of these, about 30% occur at pedestrian crossings, where pedestrians should be protected the most. Here, we propose a new accident prediction model to improve pedestrian safety assessments that allows us to accurately identify the sites with the largest potential safety improvements and define the best treatments to be applied. The accident prediction model was developed using the ISTAT dataset, including information about the fatal and injurious crashes that occurred in Italy in a 5-year period. The model allowed us to estimate the risk level of a road section through a machine-learning approach. Gradient Boosting seems to be an appropriate tool to fit classification models for its flexibility that allows us to capture non-linear relationships that would be difficult to detect via a classical approach. The results show the ability of the model to p...
Because of potential differences between national and local conditions, the Mechanistic–Empirical... more Because of potential differences between national and local conditions, the Mechanistic–Empirical Pavement Design Guide (MEPDG) should be calibrated to a local level. Arkansas has invested heavily in efforts to implement the MEPDG. This paper summarizes the initial local calibration of flexible pavement models in the MEPDG for Arkansas. Data from the Long-Term Pavement Performance (LTPP) database and local pavement management system (PMS) were used. The solver function in Microsoft Excel was used to optimize the coefficients for alligator cracking. Iterative runs of the MEPDG by means of discrete calibration coefficients were conducted to optimize rutting models. In general, the alligator cracking and rutting models are improved by calibration. However, a question remains about the suitability of the calibrated models for routine design. Many default values were used in the MEPDG because of a lack of data. It is recommended that additional sites be established and a more robust data collection procedure be implemented for future calibration efforts. The difference in the definitions of transverse cracking between the MEPDG and the LTPP may be critical to data collection and identification. Thermal cracking should be specifically identified in a transverse cracking survey to calibrate the transverse cracking model in MEPDG. The procedure using LTPP and PMS data for local calibration of the MEPDG in Arkansas is established. Additional development of database software for data manipulation, preprocessing, and quality control—under way in Arkansas—will significantly streamline the calibration process.
The PRACT Project (Predicting Road ACcidents-a Transferable methodology across Europe) is an ongo... more The PRACT Project (Predicting Road ACcidents-a Transferable methodology across Europe) is an ongoing project aimed at developing a European accident prediction model structure that could, with proper calibration, be applied to different European road networks. The core principles behind the PRACT project structure are that: it is unrealistic to think that one unique Accident Prediction Model (APM) model with a unique set of Crash Modification Factors (CMFs) can actually be developed, valid for all Europe and for all the different type of networks; the development of a specific APM model and a set of CMFs based on local data is extremely time consuming and expensive and requires data and experience that most road administrations do not have; the development of "local" CMFs only based on historical local data prevents the possibility of evaluating the effectiveness of new technologies. The PRACT project addresses these issues by developing a practical guideline and a user friendly tool that will allow for an easier implementation of APMs and CMFs in different countries and on different road networks.
This is the SAVeRS project deliverable and not an official CEDR Publication. If and when a CEDR p... more This is the SAVeRS project deliverable and not an official CEDR Publication. If and when a CEDR publication will be issued this will be posted on the CEDR website (www.cedr.fr) and it could be an amended document as compared to this project Deliverable.
Sustainability, Eco-efficiency, and Conservation in Transportation Infrastructure Asset Management, 2014
ABSTRACT One of the most used tool for pavement design is the AASHTO Mechanistic-Empirical Paveme... more ABSTRACT One of the most used tool for pavement design is the AASHTO Mechanistic-Empirical Pavement Design Guide (M-E PDG) which is a very powerful pavement design tool but it includes empirical distress models calibrated only for conventional bituminous materials. Nowadays non conventional asphalt concrete materials as porous asphalt concrete for wearing courses, modified asphalt concrete and cement-bitumen treated materials are often used in flexible and semirigid pavements. The implementation of these materials in the M-E PDG tool requires the calibration of the distress models based on experimental data from in-service pavements or laboratory test results. In this paper the calibration of the M-E PDG Asphalt Concrete Fatigue and Asphalt Concrete Rutting models is presented for the three type of non conventional materials mentioned above. The results are presented in terms of calibration procedure, resulting calibration factors, caveats and accuracy of the calibrated functions.
ABSTRACT This paper deals with the evaluation of the interaction between a safety barrier and a v... more ABSTRACT This paper deals with the evaluation of the interaction between a safety barrier and a variable message sign (VMS) that is placed very close to the carriageways in order to reduce the length of the arm above the carriageways. The two issues addressed are the structural response of the VMS, in order to ensure that the structure will not fail under the impact of a heavy goods vehicle (HGV), and the effects of the secondary impact that occurs when the barrier or the vehicle hits the VMS structure. These issues have been analysed both in terms of overall performance of the barrier and of the resulting effects on the HGV itself. As a result, the minimum distance between the front of the barrier and the VMS support structure that will enable to have a performance fully compatible with the requirements of EN1317-2:2010 has been defined for a specific barrier/VMS system.
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Papers by Monica Meocci