There has been various design methods for roller compacted concrete (RCC) pavement during a sever... more There has been various design methods for roller compacted concrete (RCC) pavement during a several decades. These design procedure are developed gradually. In this paper a 3D finite element (FE) model of RCC pavement has been developed. . In the validation step, the results of 3D modelling are compared with those obtained by theoretical approach. The comparison shows good correspondences. Due to the fact the theoretical approach uses 2D model in the formula, the 3D FE model results were slightly lower than the theoretical model. Using finite element software ABAQUS software, the paper investigated effects of changes speed in vertical displacement. In order to find the effect of speed in typical RCC pavement with the assumed properties in section 3, five partition for the applying load has created on the surface of slab. Vertical displacement at the bottom of the surface layer has been achieved for six different speed. Considering the obtained results of vertical displacement of the...
Transportation Research Record: Journal of the Transportation Research Board, 2021
Periodic measurement and identification of the presence and severity of pavement rutting are cruc... more Periodic measurement and identification of the presence and severity of pavement rutting are crucial for pavement management programs conducted by state transportation agencies. This paper proposes a novel analytical method for identifying pavement rutting locations using data collected by mobile terrestrial LiDAR scanning (MTLS). Four vendor MTLS systems were evaluated based on their ability to accurately reproduce a roadway’s transverse profile. To establish ground-truth measurements, 2 in. interval pavement transverse profiles, which included rutting sections, were collected using traditional surveying techniques. MTLS transverse profiles were evaluated using partial curve mapping, Fréchet distance, area, curve length, and dynamic time warping techniques. Resultant pavement transverse profiles were compared between vendors and a profile created from traditional surveying. Results indicate that calibrated MTLS systems can provide accurate transverse profiles for potential identifi...
Transportation Research Record: Journal of the Transportation Research Board, 2020
Over the past several years, traffic fatality rates in South Carolina have been consistently rank... more Over the past several years, traffic fatality rates in South Carolina have been consistently ranked among the highest in the country. Furthermore, South Carolina incurs an annual economic loss of over two billion dollars because of roadway traffic crashes. The South Carolina Department of Transportation, in collaboration with the South Carolina Department of Public Safety, has undertaken a series of initiatives to reduce the number of vehicle crashes, with a particular emphasis on injury and fatal crashes. One of these initiatives is the deployment of a map-based geocoded crash reporting system that has greatly improved the quality of crash location data. This paper provides an assessment of improvements in crash geocoding accuracy in South Carolina and how improved accuracy is beneficial to systematic statewide safety analysis. A case study approach is used to demonstrate practical applications and analysis techniques based on spatially accurate crash data. A survey of U.S. state h...
Transportation Research Record: Journal of the Transportation Research Board, 2019
The AASHTO Highway Safety Manual (HSM) presents a variety of methods for quantitatively estimatin... more The AASHTO Highway Safety Manual (HSM) presents a variety of methods for quantitatively estimating crash frequency or severity at a variety of locations. The HSM predictive methods require the roadway network to be divided into homogeneous segments and intersections, or sites populated with a series of attributes. It recommends a minimum segment length of 0.1 mi. This research focuses on segment lengths of less than 0.1 mi for statewide screening of midblock crash locations to identify site specific locations with high crash incidence. The paper makes an argument that many midblock crashes can be concentrated along a very short segment because of an undesirable characteristic of a specific site. The use of longer segments may “hide” the severity of a single location if the rest of the segment has few or no additional crashes. In actuality, this research does not divide sections of roads into short segments. Instead, a short-window approach is used. The underlying road network is use...
Transportation Research Record: Journal of the Transportation Research Board, 2018
Ensuring adequate pavement cross-slope on highways can improve driver safety by reducing the pote... more Ensuring adequate pavement cross-slope on highways can improve driver safety by reducing the potential for ponding to occur or vehicles to hydroplane. Mobile laser scanning (MLS) systems provide a rapid, continuous, and cost-effective means of collecting accurate 3D coordinate data along a corridor in the form of a point cloud. This study provides an evaluation of MLS systems in terms of the accuracy and precision of collected cross-slope data and documentation of procedures needed to calibrate, collect, and process this data. Mobile light detection and ranging (LiDAR) data were collected by five different vendors on three roadway sections. The results indicate the difference between ground control adjusted and unadjusted LiDAR derived cross-slopes, and field surveying measurements less than 0.19% at a 95% confidence level. The unadjusted LiDAR data incorporated corrections from an integrated inertial measurement unit and high-accuracy real-time kinematic GPS, however it was not pos...
According to the historical crash data, there is a growing concern about motor vehicle collisions... more According to the historical crash data, there is a growing concern about motor vehicle collisions involving pedestrians in Iran. Using pedestrian traffic accident records (2012-2013) from Mashhad department of Transportation as a case study, this paper applied spatial analysis of traffic accidents using geographic information system (GIS) tool. The paper aimed to identify clusters of injured pedestrians using network Kernel Density Estimation (KDE) method and ordinary Kriging analysis. The resulting geostatistical model, discovered critical threshold zones for higher injury pedestrian crash prone urban area in the case study. Considering the fact that the output are limited to the case study, the results identified by the two methods were found to be moderately similar in identifying hotspots. In addition, the study have shown that Kriging technique could be used for road safety as a promising tool. The developed criteria will assist the system managers not only in Mashhad, but also nationally, in better understanding the cause of the crashes and identifying appropriate operating strategies to improve pedestrian safety.
There has been various design methods for roller compacted concrete (RCC) pavement during a sever... more There has been various design methods for roller compacted concrete (RCC) pavement during a several decades. These design procedure are developed gradually. In this paper a 3D finite element (FE) model of RCC pavement has been developed. . In the validation step, the results of 3D modelling are compared with those obtained by theoretical approach. The comparison shows good correspondences. Due to the fact the theoretical approach uses 2D model in the formula, the 3D FE model results were slightly lower than the theoretical model. Using finite element software ABAQUS software, the paper investigated effects of changes speed in vertical displacement. In order to find the effect of speed in typical RCC pavement with the assumed properties in section 3, five partition for the applying load has created on the surface of slab. Vertical displacement at the bottom of the surface layer has been achieved for six different speed. Considering the obtained results of vertical displacement of the...
Transportation Research Record: Journal of the Transportation Research Board, 2021
Periodic measurement and identification of the presence and severity of pavement rutting are cruc... more Periodic measurement and identification of the presence and severity of pavement rutting are crucial for pavement management programs conducted by state transportation agencies. This paper proposes a novel analytical method for identifying pavement rutting locations using data collected by mobile terrestrial LiDAR scanning (MTLS). Four vendor MTLS systems were evaluated based on their ability to accurately reproduce a roadway’s transverse profile. To establish ground-truth measurements, 2 in. interval pavement transverse profiles, which included rutting sections, were collected using traditional surveying techniques. MTLS transverse profiles were evaluated using partial curve mapping, Fréchet distance, area, curve length, and dynamic time warping techniques. Resultant pavement transverse profiles were compared between vendors and a profile created from traditional surveying. Results indicate that calibrated MTLS systems can provide accurate transverse profiles for potential identifi...
Transportation Research Record: Journal of the Transportation Research Board, 2020
Over the past several years, traffic fatality rates in South Carolina have been consistently rank... more Over the past several years, traffic fatality rates in South Carolina have been consistently ranked among the highest in the country. Furthermore, South Carolina incurs an annual economic loss of over two billion dollars because of roadway traffic crashes. The South Carolina Department of Transportation, in collaboration with the South Carolina Department of Public Safety, has undertaken a series of initiatives to reduce the number of vehicle crashes, with a particular emphasis on injury and fatal crashes. One of these initiatives is the deployment of a map-based geocoded crash reporting system that has greatly improved the quality of crash location data. This paper provides an assessment of improvements in crash geocoding accuracy in South Carolina and how improved accuracy is beneficial to systematic statewide safety analysis. A case study approach is used to demonstrate practical applications and analysis techniques based on spatially accurate crash data. A survey of U.S. state h...
Transportation Research Record: Journal of the Transportation Research Board, 2019
The AASHTO Highway Safety Manual (HSM) presents a variety of methods for quantitatively estimatin... more The AASHTO Highway Safety Manual (HSM) presents a variety of methods for quantitatively estimating crash frequency or severity at a variety of locations. The HSM predictive methods require the roadway network to be divided into homogeneous segments and intersections, or sites populated with a series of attributes. It recommends a minimum segment length of 0.1 mi. This research focuses on segment lengths of less than 0.1 mi for statewide screening of midblock crash locations to identify site specific locations with high crash incidence. The paper makes an argument that many midblock crashes can be concentrated along a very short segment because of an undesirable characteristic of a specific site. The use of longer segments may “hide” the severity of a single location if the rest of the segment has few or no additional crashes. In actuality, this research does not divide sections of roads into short segments. Instead, a short-window approach is used. The underlying road network is use...
Transportation Research Record: Journal of the Transportation Research Board, 2018
Ensuring adequate pavement cross-slope on highways can improve driver safety by reducing the pote... more Ensuring adequate pavement cross-slope on highways can improve driver safety by reducing the potential for ponding to occur or vehicles to hydroplane. Mobile laser scanning (MLS) systems provide a rapid, continuous, and cost-effective means of collecting accurate 3D coordinate data along a corridor in the form of a point cloud. This study provides an evaluation of MLS systems in terms of the accuracy and precision of collected cross-slope data and documentation of procedures needed to calibrate, collect, and process this data. Mobile light detection and ranging (LiDAR) data were collected by five different vendors on three roadway sections. The results indicate the difference between ground control adjusted and unadjusted LiDAR derived cross-slopes, and field surveying measurements less than 0.19% at a 95% confidence level. The unadjusted LiDAR data incorporated corrections from an integrated inertial measurement unit and high-accuracy real-time kinematic GPS, however it was not pos...
According to the historical crash data, there is a growing concern about motor vehicle collisions... more According to the historical crash data, there is a growing concern about motor vehicle collisions involving pedestrians in Iran. Using pedestrian traffic accident records (2012-2013) from Mashhad department of Transportation as a case study, this paper applied spatial analysis of traffic accidents using geographic information system (GIS) tool. The paper aimed to identify clusters of injured pedestrians using network Kernel Density Estimation (KDE) method and ordinary Kriging analysis. The resulting geostatistical model, discovered critical threshold zones for higher injury pedestrian crash prone urban area in the case study. Considering the fact that the output are limited to the case study, the results identified by the two methods were found to be moderately similar in identifying hotspots. In addition, the study have shown that Kriging technique could be used for road safety as a promising tool. The developed criteria will assist the system managers not only in Mashhad, but also nationally, in better understanding the cause of the crashes and identifying appropriate operating strategies to improve pedestrian safety.
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Papers by Afshin Famili