Download or read book Accident Countermeasures at High speed Signalized Intersections written by Ronald W. Eck and published by . This book was released on 1984 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advance warning including flashing signs and strobe lights. Survey of traffic engineers at state and local agencies.

Download or read book Synthesis of Practice on Accident Countermeasures at High speed Signalized Intersections written by Ronald W. Eck and published by . This book was released on 1984 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Low cost Safety Enhancements for Stop controlled and Signalized Intersections written by and published by . This book was released on 2009 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The purpose of this document is to present information on suggested effective, low-cost intersection countermeasures developed using intersection safety research results and input from an intersection safety expert panel. These low-cost countermeasures can be applied to a large number of intersections with a high frequency of crashes using a systematic approach. The net impact of such an approach can produce significant reductions in statewide intersection crashes, fatalities, and serious injuries. Low-cost countermeasures are defined as those ranging from $1,000 to $50,000 per intersection"--Page 4

Download or read book Evaluation of High speed Isolated Signalized Intersections in California written by Simon Washington and published by . This book was released on 1991 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: High-speed isolated signalized intersections (HSISI's) are generally encountered after long uninterrupted and uncongested flow conditions, thereby catching some motorists by surprise. For this reason alone, approaches to HSISI's need to have safe and effective warning, control, and intersection geometric treatments. This research identified characteristics at California HSISI's that relate to accident rates. A data base consisting of approximately 100 intersection and approach variables was established and used to investigate advance warning, signal timing and phasing, channelization, signal equipment configurations, shoulder widths and types, median widths and types, and approach speeds.

Download or read book Making Intersections Safer written by Hugh W. McGee and published by . This book was released on 2003 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Roadway Safety written by Brian E. Chandler and published by Momentum Press. This book was released on 2016-03-02 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces the basics of safety needs identification, countermeasure selection, and implementation of treatments designed to reduce the number of roadway crashes and resulting injuries and fatalities. It describes the current state of the practice and research regarding finding roadway safety issues, choosing treatments, and implementing their installation. The book also focuses on crashes occurring at intersections, work zones, and as the result of a lane departure.

Download or read book Safety Effectiveness of High speed Expressway Signals written by Reginald R. Souleyrette and published by . This book was released on 2005 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The safety benefit of signalizing intersections of high-speed divided expressways is considered. Analyses were conducted on 50 and 55 mph and on 55 mph only intersections, comparing unsignalized and signalized intersections. Results of the 55 mph analysis are included in this report. Matched-pair analysis indicates that generally, signalized intersections have higher crash rate but lower costs per crash. On the other hand, before-and-after analysis (intersections signalized between 1994 and 2001) indicates lower crash rates (~30 percent) and total costs (~10 percent) after signalization. Empirical Bayes (EB) adjusted before-and-after analysis reduces estimates of safety benefit (crash rate) to about 20 percent. The study shows how commonly used analyses can differ in their results, and that there is great variability in the safety performance of individual signalized locations. This variability and the effect of EB adjustment are demonstrated through the use of innovative graphics.

Download or read book Examination of Signalized Intersection Straight Crossing Path Crashes and Potential IVHS Countermeasures written by and published by . This book was released on 1994 with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advance Detection on High speed Signalized Intersection Approaches written by Patrick T. McCoy and published by . This book was released on 2002 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Symposium on Effective Highway Accident Countermeasures written by and published by . This book was released on 1990 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Symposium on Effective Highway Accident Countermeasures was held in Washington, D.C., on June 12-14, 1990. The Symposium was hosted by the Federal Highway Administration in cooperation with the National Highway Traffic Safety Administration. The Symposium's objectives were to identify the most effective and practical short-term (within 2 years) countermeasures to highway accidents and to develop strategies for their implementation. The Symposium focused on five areas of highway safety: improving pedestrian safety, reducing accident severity, improving driver performance and control, improving commercial motor vehicle safety, and identifying and improving highway corridors. This publication summarizes the presentations and workshop reports.

Download or read book Developing Safety Performance Functions for Wyoming Urban and Suburban Four leg Signalized Intersections written by Sadia Sharmin and published by . This book was released on 2018 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: The complexity of traffic movements at signalized intersections is of a significant interest to transportation professionals due to a disproportional high amount of conflicts and crashes involving turning vehicles followed by through vehicles. Moreover, the wide variability in geometric and operational characteristics at signalized intersections may exacerbate this complexity. Intersection-related fatalities in Wyoming exhibited a sharp increase after 2012. Fatality rate in Wyoming exceeded the national rate by 12 percent in 2014 and 2015. In 2015, Wyoming’s urban intersections crashes constituted 50% of total urban crashes while that the proportion at the national level in the US was 32%. These issues could be addressed through successful engineering approaches which necessitate reliable methods to estimate intersection safety. Currently, Safety Performance Functions (SPFs) are used as the main tool to estimate traffic safety of different roadway elements including intersections. The Highway Safety Manual (HSM), published by the American Association of State Highway and Transportation Officials (AASHTO) in 2010 provides SPFs for intersections. The unique nature and distinct attributes of Wyoming also necessitates developing its own jurisdiction-specific SPFs. SPFs are needed to identify potential candidate locations for safety improvements and for implementation of various safety countermeasures. Therefore, the research in this thesis focuses on calibrating SPFs for four-leg signalized intersections in Wyoming. The thesis also utilizes advanced statistical techniques to address various issues in crash data at intersections. Crash data at four-leg signalized intersections were structured as pooled data averaged across time and panel data with respect to time. The key issues addressed in this study include: i) addressing overdispersion characteristics of crash data, ii) considering unobserved random effects of the intersections due to their heterogeneity, and iii) allowing the effects of the confounding factors on intersection crash trends over time. This study examined the effects of geometry, weather, traffic and driver characteristics on crash frequencies incorporating time trends and taking longer time frames into consideration. Standard crash models using longer time frames and aggregated data do not consider time-varying effects on crash frequency, and can introduce error due to unobserved heterogeneity. This study analyzed the findings among traditional Negative Binomial (NB) model (using pooled and panel data) which account for the overdispersion of data, Random Effect Negative Binomial (RENB) model using panel data that consider unobserved random effects of the sites due to their heterogeneity and Generalized Estimating Equation (GEE) with Negative Binomial (NB) distribution. RENB model outperformed NB models by comparing the Akaike Information Criterion (AIC) values and hence, RENB models were chosen to explain the effects of the confounding factors on the crash counts. A marginal model approach which is different from the random effect approach was attempted through applying GEE to the panel data. “Time” was included as an explanatory variable with linear and quadratic effects to investigate the crash trends across time. The interactions of variables with “time” were considered to determine the effect of fixed variables over time. GEE was also fitted using variables without incorporating “time”, however, GEE accounting for “time” performed better. Model assessment was performed using the quasi-likelihood information criterion (QIC). This method also showed that the GEE model with autoregression structure had the best model performance. Installing left-turn lanes at signalized intersections physically separates left-turning vehicles, hence can reduce the number of conflicts by removing slow or decelerating vehicles from through traffic resulting in safer operations. The safety effectiveness of left-turn lanes at four-leg signalized intersections was estimated with these approaches along with predicting and describing the confounding factors. The aforementioned objectives were attained by developing SPFs using 174 four-leg signalized intersections crash data of Wyoming from the years 2005 through 2014. Wyoming specific data, including traffic, weather and driver characteristics, were incorporated into the models along with site-specific geometric characteristics. The results of this study highlighted the advantages of predicting crash frequencies by crash type and severity. To examine the impact of weather on intersections crashes, three sets of SPFs were calibrated; winter, summer, and all year. The cross-sectional panel data analysis for evaluating the safety effectiveness of adding left-turn lanes at four-leg signalized intersections indicated a reduction of Fatal+Injury (F+I) and angle crashes by 21.6% and 30.8%, respectively. The calibrated models for the winter indicated a reduction of 19.4% and 38.8% for the aforementioned crashes, respectively for adding left-turn lanes. For the summer, crash reduction for these crashes for the same treatment were found 71% and 69%, respectively.

Download or read book Effective Highway Accident Countermeasures written by United States. Federal Highway Administration and published by . This book was released on 1991 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: This action plan addresses the short-term countermeasures and recommendations developed by safety professionals and practitioners from Federal, State, local and private sector organizations attending the Symposium on Effective Highway Accident Countermeasures, June 1990, Washington, D.C. It focuses on 11 priority short-term countermeasures deemed to have high payoff within the next two years. These are grouped under five categories: Pedestrian Safety Improvements; Driver Behavior and Performance; Roadway and Roadside Safety; Commercial Motor Vehicle Safety; and Corridor Safety Improvement Programs.

Download or read book The Relation Between Accidents and Traffic Volumes at Signalized Intersections written by George M. Webb and published by . This book was released on 1955 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Driver Response in Active Advanced Warning Signs at High speed Signalized Intersections Final Report written by Z. A. Sabra and published by . This book was released on 1985 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Our Nation s Highways written by and published by . This book was released on 1995 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Speed Management written by European Conference of Ministers of Transport and published by OECD Publishing. This book was released on 2006-10-13 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: Speeding is the number one road safety problem in a large number of OECD/ECMT countries. It is responsible for around one third of the current, unacceptably high levels of road fatalities. Speeding has an impact not only on accidents but also on the ...

Download or read book A Comparative Analysis of Different Dilemma Zone Countermeasures at Signalized Intersections Based on Cellular Automaton Model written by Yina Wu and published by . This book was released on 2014 with total page 167 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the United States, intersections are among the most frequent locations for crashes. One of the major problems at signalized intersection is the dilemma zone, which is caused by false driver behavior during the yellow interval. This research evaluated driver behavior during the yellow interval at signalized intersections and compared different dilemma zone countermeasures. The study was conducted through four stages. First, the driver behavior during the yellow interval were collected and analyzed. Eight variables, which are related to risky situations, are considered. The impact factors of drivers' stop/go decisions and the presence of the red-light running (RLR) violations were also analyzed. Second, based on the field data, a logistic model, which is a function of speed, distance to the stop line and the lead/follow position of the vehicle, was developed to predict drivers' stop/go decisions. Meanwhile, Cellular Automata (CA) models for the movement at the signalized intersection were developed. In this study, four different simulation scenarios were established, including the typical intersection signal, signal with flashing green phases, the intersection with pavement marking upstream of the approach, and the intersection with a new countermeasure: adding an auxiliary flashing indication next to the pavement marking. When vehicles are approaching the intersection with a speed lower than the speed limit of the intersection approach, the auxiliary flashing yellow indication will begin flashing before the yellow phase. If the vehicle that has not passed the pavement marking before the onset of the auxiliary flashing yellow indication and can see the flashing indication, the driver should choose to stop during the yellow interval.