hintcad road safety analysis system
brief introduction
the actual operating speed of vehicle is one of the main basis criteria of hintcad safety analysis system of highway alignment design. the system can effectively check and analyze the collocation between the design speed and the main design parameters of horizontal, profile and cross section of the route as well as related elements such as sight distance, super elevation and so on, to obtain a continuous, consistent and balanced design.
1. concept and characteristics of the operating speed
means the speed at which 85% of drivers drive lower than on the specific road section under clean, damp conditions, referred to as the v85. the operating speed synthetically considers the following factors:
overall consideration of driver behavior, psychological and visual demand, vehicle performance and characteristics, alignment geometric design factors.
checking calculation model of operating speed is generalized after observing the actual running speed of vehicles on a typical highway, after gathering statistics and analyzing data distribution. the actual operating speed of vehicle is one of main basis of alignment design, which can effectively ensure the reasonable match between the design speed and main design parameters of horizontal, profile and cross section as well as related elements such as sight distance, super elevation, in order to obtain continuous, consistent and balanced design.
2. research and application of operating speed in china
in 2000, highway bureau of ministry of transportation hold a special research on design method and standard of operating speed on highway during the study of the standard and specification projects. the research carried out a large variety of actual investigation on actual running speed on many representative highways and first grade highway, after statistical analysis of observational data of the actual operating speed, established predicting model of speed under horizontal and longitudinal alignment index, suitable for the characteristics of drivers, vehicle dynamic and highway.
in nov.2004, ministry of transportation issued safety evaluation guide for highway engineering, the calculation method and evaluation standard, the research results of design method and standard of operating speed on highway, was entered to be the recommended standard of highway industry and was recommended to be adopted in the whole industry.
the promotion of operating speed application to be the main index of highway safety design, which will guide our highway design work to pay more attention to the “human-oriented, focus on safety” and other new concepts, in order to eliminate some hidden dangers in the design phase, reflect dynamic design and consider driving behavior. so, based on the design data of horizontal, profile and cross section, analyzing the checking calculation of operating speed, the analysis results will guide the route design and optimization, which will gradually become an indispensable part of our highway design work(process).
3. development basis and application of hintcad checking calculation analysis system of operating speed
based on the insufficient design speed and inadaptability of the running speed, existing technical standards of highway engineering recommends that we should use operating speed v85 to check the design speed change sections, climbing lane, super elevation and other restricted road sections in highway design , to ensure that the highway geometric alignment design can meet the requirement of the actual vehicle, the coordination and balance and so on between design elements .meanwhile, in 2006, the formally promulgated design specifications of highway route also requires the designers to implement analysis and calculation of operating speed, so as to select the concrete roadbed super elevation by combining with the characteristics of different projects.
however, many designers just begin to understand the concept of operating speed, so they rarely know the process of specific checking calculation and analysis, moreover, the specific calculation model is complex, the route segmentation process is cumbersome, which leads to the consequence that they only did a simplified manual calculation for individual section of the project(such as only consider the influence of horizontal curve, or carry out calculation only considering the influence of longitudinal slope) in their actual design work and safety evaluation work, instead of according to the requirements of the guide to carry through a comprehensive checking calculation analysis on two driving directions of the entire route, on the premise of considering the combined influence factors of horizontal , profile and cross section at the same time.
the development of hintcad checking calculation and analysis system of operating speed is just based on the research results of design method and standard of operating speed on highway, combined with the requirements of safety evaluation guide of highway projects, meanwhile, refers to the method and standard of establishment of operating speed in australia, the united states and so on. the system is getting more sophisticated and mature after nearly more than one year of research, development and practical application by many mountainous highway projects. at present, the system has passed the software evaluation and identification from relevant authorities.
4. brief description of main function of hintcad analysis system of operating speed
directly reads basic data of route design of hintcad 3d road cad system; based on checking calculation model of operating speed, automatically achieves combination and segmentation of route alignment unit; (meanwhile supports user’s continuous segmentation adjustment); checks and calculates the unit node speed under full route forward and backward driving conditions in accordance with the revised checking calculation model of operating speed; based on the data of node operating speed after checking calculation ,automatically drafts and outputs node speed change chart of full route forward and backward operating speed, operating speed gradient map and so on ,automatically outputs forward and backward node speed change table etc; provides cautionary identity for the road section with hidden danger automatically based on standards, norms and guides; combined with hintcad road 3d roaming system platform, applies spatial inter-visibility model between two points , utilizes pavement point-by-point scanning method, achieves the comparison and analysis on design sight distance, operating sight distance and spatial sight distance, and outputs comparative analysis drawing; combining with hintcad road 3d roaming system platform, automatically detects analysis results of driving stability of vehicle and super elevation set under operating speed conditions.
5. characteristics and technological innovation of hintcad analysis system of operating speed
(1). provides a systematic, scientific, rational and specific method to evaluate the highway alignment design from aspect of driving safety.
the system uses checking calculation model，deep researches the relation between highway geometric index and operating speed combined with traffic accidents, meanwhile, by reference to the establishment method and standard of operating speed in europe, america and so on, the analysis and evaluation of the system is established on the basis of statistical analysis of actual running speed data on a large number of representative highway and the first class highway in china, and ultimately achieves a reliable checking calculation model and analysis method of operating speed , which is suitable for driving characteristics. completely changes the status that designers carry out highway design only based on design specifications or some design experience.
(2). the characteristics of the system are friendly interface, easy operation, and high intelligence, strong professional, combined closely with actual engineering design, in accordance with industrial standard, flexible application and so on. and providing a comprehensive, informative, scientific and reliable drawing and document achievement. the chart is intuitive and of high automation.
(3). highly integrated with the most popular hintcad 3d road cad system, which is highly integrated with hintcad route design system, directly reading design result data to carry out checking calculation of operating speed and analysis , outputting results are common formats such as *.dwg, *.xls.
(4). the system is integrating with hintcad road roaming system, achieving composite analysis and evaluation matching system and technology.
6. suitability and application of the system
hintcad checking calculation and analysis system of operating speed is the first professional software on the operating speed analysis in china, based on the basis of many years of engineering experience, test and research data, the system is researched and developed after absorbing foreign advanced experience and combining with actual highway situation of china, the system fills the gap of research analysis of operating speed software and application of computer analysis, and has reached the leading level in china.
the checking calculation model , analysis and evaluation method taken by the system is scientific and reasonable, the establishment of analysis model of operating speed is based on the statistical analysis of actual running speed data on a large number of representative highway and the first class highway , combining with traffic accidents, deeply researches on the relation between highway geometric index and operating speed, meanwhile, by reference to the establishment method and standard of operating speed in europe, america and so on, ultimately achieves a reliable checking calculation model and analysis method of operating speed , which is suitable for driving characteristics.
the system is the result of advanced engineering design concepts and computer software technology, which has friendly interface, easy operation, high intelligence, strong professional, combining closely with actual engineering design, in accordance with industrial standard, flexible application and so on. and can provide a comprehensive, informative, scientific and reliable drawing and document results.
the actual operating speed of vehicle is one of the main basis criteria of hintcad safety analysis system of highway alignment design. the system can effectively check and analyze the collocation between the design speed and the main design parameters of horizontal, profile and cross section of the route as well as related elements such as sight distance, super elevation and so on, to obtain a continuous, consistent and balanced design.
1. concept and characteristics of the operating speed
means the speed at which 85% of drivers drive lower than on the specific road section under clean, damp conditions, referred to as the v85. the operating speed synthetically considers the following factors:
overall consideration of driver behavior, psychological and visual demand, vehicle performance and characteristics, alignment geometric design factors.
checking calculation model of operating speed is generalized after observing the actual running speed of vehicles on a typical highway, after gathering statistics and analyzing data distribution. the actual operating speed of vehicle is one of main basis of alignment design, which can effectively ensure the reasonable match between the design speed and main design parameters of horizontal, profile and cross section as well as related elements such as sight distance, super elevation, in order to obtain continuous, consistent and balanced design.
2. research and application of operating speed in china
in 2000, highway bureau of ministry of transportation hold a special research on design method and standard of operating speed on highway during the study of the standard and specification projects. the research carried out a large variety of actual investigation on actual running speed on many representative highways and first grade highway, after statistical analysis of observational data of the actual operating speed, established predicting model of speed under horizontal and longitudinal alignment index, suitable for the characteristics of drivers, vehicle dynamic and highway.
in nov.2004, ministry of transportation issued safety evaluation guide for highway engineering, the calculation method and evaluation standard, the research results of design method and standard of operating speed on highway, was entered to be the recommended standard of highway industry and was recommended to be adopted in the whole industry.
the promotion of operating speed application to be the main index of highway safety design, which will guide our highway design work to pay more attention to the “human-oriented, focus on safety” and other new concepts, in order to eliminate some hidden dangers in the design phase, reflect dynamic design and consider driving behavior. so, based on the design data of horizontal, profile and cross section, analyzing the checking calculation of operating speed, the analysis results will guide the route design and optimization, which will gradually become an indispensable part of our highway design work(process).
3. development basis and application of hintcad checking calculation analysis system of operating speed
based on the insufficient design speed and inadaptability of the running speed, existing technical standards of highway engineering recommends that we should use operating speed v85 to check the design speed change sections, climbing lane, super elevation and other restricted road sections in highway design , to ensure that the highway geometric alignment design can meet the requirement of the actual vehicle, the coordination and balance and so on between design elements .meanwhile, in 2006, the formally promulgated design specifications of highway route also requires the designers to implement analysis and calculation of operating speed, so as to select the concrete roadbed super elevation by combining with the characteristics of different projects.
however, many designers just begin to understand the concept of operating speed, so they rarely know the process of specific checking calculation and analysis, moreover, the specific calculation model is complex, the route segmentation process is cumbersome, which leads to the consequence that they only did a simplified manual calculation for individual section of the project(such as only consider the influence of horizontal curve, or carry out calculation only considering the influence of longitudinal slope) in their actual design work and safety evaluation work, instead of according to the requirements of the guide to carry through a comprehensive checking calculation analysis on two driving directions of the entire route, on the premise of considering the combined influence factors of horizontal , profile and cross section at the same time.
the development of hintcad checking calculation and analysis system of operating speed is just based on the research results of design method and standard of operating speed on highway, combined with the requirements of safety evaluation guide of highway projects, meanwhile, refers to the method and standard of establishment of operating speed in australia, the united states and so on. the system is getting more sophisticated and mature after nearly more than one year of research, development and practical application by many mountainous highway projects. at present, the system has passed the software evaluation and identification from relevant authorities.
4. brief description of main function of hintcad analysis system of operating speed
directly reads basic data of route design of hintcad 3d road cad system; based on checking calculation model of operating speed, automatically achieves combination and segmentation of route alignment unit; (meanwhile supports user’s continuous segmentation adjustment); checks and calculates the unit node speed under full route forward and backward driving conditions in accordance with the revised checking calculation model of operating speed; based on the data of node operating speed after checking calculation ,automatically drafts and outputs node speed change chart of full route forward and backward operating speed, operating speed gradient map and so on ,automatically outputs forward and backward node speed change table etc; provides cautionary identity for the road section with hidden danger automatically based on standards, norms and guides; combined with hintcad road 3d roaming system platform, applies spatial inter-visibility model between two points , utilizes pavement point-by-point scanning method, achieves the comparison and analysis on design sight distance, operating sight distance and spatial sight distance, and outputs comparative analysis drawing; combining with hintcad road 3d roaming system platform, automatically detects analysis results of driving stability of vehicle and super elevation set under operating speed conditions.
(1). provides a systematic, scientific, rational and specific method to evaluate the highway alignment design from aspect of driving safety.
the system uses checking calculation model，deep researches the relation between highway geometric index and operating speed combined with traffic accidents, meanwhile, by reference to the establishment method and standard of operating speed in europe, america and so on, the analysis and evaluation of the system is established on the basis of statistical analysis of actual running speed data on a large number of representative highway and the first class highway in china, and ultimately achieves a reliable checking calculation model and analysis method of operating speed , which is suitable for driving characteristics. completely changes the status that designers carry out highway design only based on design specifications or some design experience.
(2). the characteristics of the system are friendly interface, easy operation, and high intelligence, strong professional, combined closely with actual engineering design, in accordance with industrial standard, flexible application and so on. and providing a comprehensive, informative, scientific and reliable drawing and document achievement. the chart is intuitive and of high automation.
(3). highly integrated with the most popular hintcad 3d road cad system, which is highly integrated with hintcad route design system, directly reading design result data to carry out checking calculation of operating speed and analysis , outputting results are common formats such as *.dwg, *.xls.
(4). the system is integrating with hintcad road roaming system, achieving composite analysis and evaluation matching system and technology.
hintcad checking calculation and analysis system of operating speed is the first professional software on the operating speed analysis in china, based on the basis of many years of engineering experience, test and research data, the system is researched and developed after absorbing foreign advanced experience and combining with actual highway situation of china, the system fills the gap of research analysis of operating speed software and application of computer analysis, and has reached the leading level in china.
the checking calculation model , analysis and evaluation method taken by the system is scientific and reasonable, the establishment of analysis model of operating speed is based on the statistical analysis of actual running speed data on a large number of representative highway and the first class highway , combining with traffic accidents, deeply researches on the relation between highway geometric index and operating speed, meanwhile, by reference to the establishment method and standard of operating speed in europe, america and so on, ultimately achieves a reliable checking calculation model and analysis method of operating speed , which is suitable for driving characteristics.
the system is the result of advanced engineering design concepts and computer software technology, which has friendly interface, easy operation, high intelligence, strong professional, combining closely with actual engineering design, in accordance with industrial standard, flexible application and so on. and can provide a comprehensive, informative, scientific and reliable drawing and document results.
hintcad analysis system of operating speed has a very practical basis, because at present, there are a large amount of highway projects being built and having been built (especially mountainous highway) in need of traffic safety analysis and evaluation. the system provides a whole set of method to evaluate consistency, coordination and security issues of highway alignment design, and also provides basis for taking operating speed as alignment design index selection, determines technical targets of the horizontal, profile and cross section, verifies super elevation, widening, sight distance and so on. with the further application of operating speed in the highway industry, with the further close connection between the system and the project design, the system will greatly improve design level and design concepts of highway, and enhance the overall technological level of road traffic design in china.
