El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In traffic engineering, the assessment of capacity in basic segment of freeway is a critical factor for planning, design and operational analysis of the freeway facilities. Thereby, the Highway Capacity Manual - HCM is the main guide used in many countries of the world including Perú that contain the methodology to estimate freeway capacity in traffic studies. Nevertheless, the information of vehicular traffic used for the construction of the models proposed by the HCM, reflect the characteristics of North American features. Therefore, its application in other traffic conditions, must be backed by studies of the local conditions and calibrations of the models proposed, hereby, adjusting to each city. The objetive of this research, is calibrate and compare of the HCM 2010 and HCM 2016 models, starting off the traffic engineering study in Panamericana Sur freeway located in Lima, Perú. The report will recommended the application of a calibrated model that best represents the local Peruvian conditions. The results of this study suggest that the model of calibrated capacity HCM2016, is the best representation, with a reliability of 97%, the local behavior of the basic freeway segments in function of the speed and the flow intensity. After applying the calibrated model into basic freeway segments concessioned by Rutas de Lima SAC, it was reflected that the use of the HCM2000, employed by this Company, show flow intensities within a level of service - LOS D, while, the calibrated HCM2016 shows us that those values are found, in reality, within a level of service - LOS E.

The research presented in this thesis attempts to investigate the impact of detector failure frequency and failure duration on the accuracy of loop detector speed, flow, and density measurements using a Monte Carlo simulation approach. The inputs to the model are the frequency of failures and failure duration. Several regression models were developed to relate loop detector accuracy to detector failure data. The results showed that the models were consistent and similar for the same location with an R square that ranged between 86% and 94% for all models and in comparing two locations, the differences between the regression models were minor except for the flow model errors, the location had the same trend but the magnitude of the flow RMSE increased by 7.5 to 15%. The second part of the research effort attempts to quantify the impact of inclement weather (precipitation and visibility) on traffic stream free-flow speeds along freeway sections. The analysis is conducted using weather (precipitation and visibility) and loop detector data (speed) obtained from Baltimore, Minneapolis/St. Paul, and Seattle, US. The results demonstrate that visibility alone has a minimum impact on free-flow speed with reductions in the range of 1 to 3%. These reductions only appear as the visibility level falls below 1.2 km. The study demonstrates that the impact of snow is more significant than that of rain for similar intensity levels. Reductions caused by rain are in the neighborhood of 2 to 5% depending on the precipitation intensity while reductions caused by snow are in the neighborhood of 6 to 20%. With regards to freezing rain, higher reductions in free-flow speed were observed when compared to rain and snow. Specifically, the free-flow speed was reduced by 14% at the onset of freezing rain precipitation with a maximum decrease of 27% at freezing rain intensity of about 0.53 cm/h for Baltimore and as the case of Seattle the reduction was found to be constant with 31%. Finally, the paper derives free-flow speed reduction factors that vary as a function of the precipitation type and intensity level. These reduction factors can be incorporated within the Highway Capacity Manual's procedures. / Master of Science

Probe speed data are widely used to calculate performance measures for quantifying state-wide traffic conditions. Estimation of the accurate performance measures requires adequate speed data observations. However, probe vehicles reporting the speed data may not be available all the time on each road segment. Agencies need to develop a good understanding of the adequacy of these reported data before using them in different transportation applications. This study attempts to systematically assess the quality of the probe data by proposing a method, which determines the minimum sample rate for checking data adequacy. The minimum sample rate is defined as the minimum required speed data for a segment ensuring the speed estimates within a defined error range. The proposed method adopts a bootstrapping approach to determine the minimum sample rate within a pre-defined acceptance level. After applying the method to the speed data, the results from the analysis show a minimum sample rate of 10% for Kentucky’s roads. This cut-off value for Kentucky’s roads helps to identify the segments where the availability is greater than the minimum sample rate. This study also shows two applications of the minimum sample rates resulted from the bootstrapping. Firstly, the results are utilized to identify the geometric and operational factors that contribute to the minimum sample rate of a facility. Using random forests regression model as a tool, functional class, section length, and speed limit are found to be the significant variables for uninterrupted facility. Contrarily, for interrupted facility, signal density, section length, speed limit, and intersection density are the significant variables. Lastly, the speed data associated with the segments are applied to improve Free Flow Speed estimation by the traditional model.

Since the introduction of motor vehicles, the number of fatalities and accidents has been a concern for society.The number of fatalities on roads is amongst the most common causes of mortality worldwide (WHO, 2015).Even in industrialized countries the number of fatalities remains unacceptable. Therefore, in the last decades, anumber of approaches have emerged to support and boost traffic safety towards a system free from fatalities andserious impairment outcomes. ‘Sustainable Safety’ and ‘Vision Zero’ are well-known examples aiming to avoidfatalities within the traffic system and reduce injury severity when a traffic accident is inevitable. However, thenumber of fatalities and seriously injured accidents are still relatively high. More specifically, vulnerable roadusers remain involved in fatal and serious accidents even in industrialized countries. Therefore, further advancesin traffic safety studies are needed. This thesis aims at evaluating the impact of road characteristics, traffic rulesand information provision towards a safer traffic system. The thesis is composed of five scientific papers whichsummarizes the main contributions of this work. / <p>QC 20161109</p>

En el área de la ingeniería del tráfico vehicular, referente a la planificación, diseño, y operación de la infraestructura vial de transporte, la mayoría de los países tienen como principal referencia la norma International Highway Capacity Manual-HCM dentro de sus políticas de operación de proyectos de transporte. Sin embargo, este manual refleja las características de tráfico estadounidense. Debido a esto, no es directamente aplicable para las distintas realidades de tráfico de los países. Por lo que, su aplicación debe estar respaldado por estudios de las condiciones locales y calibraciones de los modelos que se ajusten a cada región. Al identificar esta brecha de conocimiento, se realizó un estudio de operación de la autopista Panamericana Sur en la región de Lima-Perú. A partir de los datos de campo, se desarrollaron curvas de ajuste para calibrar los modelos de capacidad del HCM a las condiciones locales de tráfico limeñas. Como resultado de la investigación el modelo de capacidad calibrado HCM 2016, es el que mejor representa el comportamiento local de los segmentos básicos en función de la velocidad y la intensidad, con una confiabilidad del 97,41%. Finalmente, al aplicar el modelo calibrado en un tramo básico de la autopista panamericana sur concesionado por Rutas de Lima SAC, se vio reflejado que el uso del HCM 2000, empleado por esta empresa, muestran intensidades dentro de un nivel de servicio D, mientras que, el HCM 2016 calibrado nos indica que esos valores se encontrarían, en realidad, dentro de un nivel de servicio E. / In the traffic engineering, relating to the planning, design, and operation of transport infrastructure, the majority of countries have as main reference the International Standard Highway Capacity Manual-HCM within their policies of operation of transport projects. However, this manual reflects United States traffic characteristics. Because of this, it is not directly applicable for the different traffic realities of the countries. So, your application must be supported by studies of local conditions and of calibrations of the proposed models of traffic, in such a way that fits each región. Due to this knowledge gap, was made a study of the operation of the Panamericana Sur freeway located in Lima City. From this study, made it possible to develop adjustment curves to obtain capacity models calibrated to the analysis of limeñas freeway operation. The results of the research, indicates that the model calibrated HCM2016, is the best that represents the local behavior of the basic segments freeway as a function of speed and intensity, with a reliability of 97.41%. In applying the model calibrated on basic freeway segments of the Panamericana Sur concessioned by Rutas de Lima SAC, reflected that the use of the HCM2000, employed by this company, show intensities within a service level D, while, the calibrated HCM2016 indicates that these values ​​would be actually within a service level E. / Tesis

Die vorliegende Dissertationsschrift widmet sich der Beschreibung des Geschwindigkeits-verhaltens von Kraftfahrern auf innerörtlichen Straßen sowie dessen Auswirkungen auf die Verkehrssicherheit. Grundlage bilden manuelle und automatische Querschnittsmessungen von Einzelgeschwindigkeiten in Hauptverkehrs- und Erschließungs¬straßen mit zulässigen Höchstgeschwindigkeiten von 50 bzw. 30 km/h. Die Beschreibung von Wunschgeschwindigkeiten über unterschiedliche Abgrenzungen freifahrender Fahrzeuge, deren Geschwindigkeiten die Grundlage für die folgenden Modelle bilden, sowie die Überprüfung der Übertragbarkeit von Querschnittsmessungen auf die Strecke und die Analyse von Geschwindigkeitsganglinien dienen der Einordnung der in dieser Untersuchung vorgelegten Ergebnisse. Ziel des ersten Teils der Arbeit ist die Beschreibung möglicher Einflussfaktoren aus der Gestaltung, dem Betrieb sowie der Lage im Netz und dem Umfeld einer Straße auf die Wahl der Geschwindigkeit von Pkw-Fahrern. Erste Ansätze werden aus dem Vergleich von fahrtrichtungsbezogenen Geschwindigkeiten an einem Querschnitt mit asymmetrischer Gestaltung abgeleitet. Auf Basis querschnittsbezogener mittlerer und v85-Geschwindigkeiten werden verschiedene multiple Regressionsmodelle aufgestellt und miteinander verglichen. Die Modelle basieren auf Messungen im Straßennetz Dresdens und werden anhand von Messungen aus anderen deutschen Städten validiert. Signifikante Einflussgrößen ergeben sich aus den Bereichen Verkehrsbedeutung, Querschnittsgestaltung, Umfeldnutzung und Fahrbahnoberfläche eines Straßenquerschnitts. Die Einflussgrößen sowie deren Abhängigkeiten untereinander werden diskutiert und Potenziale für Maßnahmen zur Geschwindigkeitsreduzierung aufgezeigt. Im zweiten Teil der Arbeit werden für Tempo-50-Straßen verallgemeinerte lineare Modelle zur Beschreibung des Einflusses der Geschwindigkeit auf die Verkehrssicherheit abgeleitet. Für unterschiedliche Unfallkollektive bezüglich räumlicher Abgrenzung, Unfallschwere und Verkehrsbeteiligung wird der Geschwindigkeitseinfluss auf die Unfallzahl anhand einer Potenzfunktion (Power-Modell) unter Kontrolle der Randbedingungen Verkehrsaufkommen des motorisierten Individual-verkehrs und Umfeldnutzung beschrieben. Die Zahl der Unfälle mit Personenschaden steigt progressiv mit der mittleren Geschwindigkeit und degressiv mit dem DTV an. / Driving speeds of personal vehicles on urban roads are analyzed and their influence on traffic safety is modeled. The speed data is measured at cross sections on major and minor roads with speed limits of 50 and 30 km/h. Different kinds of classification of free-flow-vehicles were analyzed for the description of the desired speed of a driver. Also local speeds along road sections as well as time variation curves of driving speeds are documented in order to interpret and classify the provided findings. The first part of this work deals with the prediction of local driving speeds based on parameters of the roadway environment determining road design as well as the land-use next to the road. One first simple approach is to compare both driving directions at non-symmetric cross sections. Then several multiple regression models for mean speeds and 85-percentiles of the speed distribution are estimated and compared with each other. The models are based on the road network of the city of Dresden and are validated with speed measurements in other German cities. Road classification, cross section characteristics, land-use and the road surface condition are found to be significant parameters that correlate with driving speed. The possible influences on the choice of speed and their interdependencies as well as their practical relevance are discussed. In the second part of this work the influence of speeds on the occurrence of traffic accidents is estimated using Generalized Linear Models. This is done for different accident groups under consideration of the annual daily traffic and a parameter that describes the length and type of land-use of the adjacent buildings next to the road section. The relationship between speed and accident counts can be described using a power function. Accident numbers rise progressively with increasing speeds and rise in a declining manner with increasing amount of traffic.

Die vorliegende Dissertationsschrift widmet sich der Beschreibung des Geschwindigkeits-verhaltens von Kraftfahrern auf innerörtlichen Straßen sowie dessen Auswirkungen auf die Verkehrssicherheit. Grundlage bilden manuelle und automatische Querschnittsmessungen von Einzelgeschwindigkeiten in Hauptverkehrs- und Erschließungs¬straßen mit zulässigen Höchstgeschwindigkeiten von 50 bzw. 30 km/h. Die Beschreibung von Wunschgeschwindigkeiten über unterschiedliche Abgrenzungen freifahrender Fahrzeuge, deren Geschwindigkeiten die Grundlage für die folgenden Modelle bilden, sowie die Überprüfung der Übertragbarkeit von Querschnittsmessungen auf die Strecke und die Analyse von Geschwindigkeitsganglinien dienen der Einordnung der in dieser Untersuchung vorgelegten Ergebnisse. Ziel des ersten Teils der Arbeit ist die Beschreibung möglicher Einflussfaktoren aus der Gestaltung, dem Betrieb sowie der Lage im Netz und dem Umfeld einer Straße auf die Wahl der Geschwindigkeit von Pkw-Fahrern. Erste Ansätze werden aus dem Vergleich von fahrtrichtungsbezogenen Geschwindigkeiten an einem Querschnitt mit asymmetrischer Gestaltung abgeleitet. Auf Basis querschnittsbezogener mittlerer und v85-Geschwindigkeiten werden verschiedene multiple Regressionsmodelle aufgestellt und miteinander verglichen. Die Modelle basieren auf Messungen im Straßennetz Dresdens und werden anhand von Messungen aus anderen deutschen Städten validiert. Signifikante Einflussgrößen ergeben sich aus den Bereichen Verkehrsbedeutung, Querschnittsgestaltung, Umfeldnutzung und Fahrbahnoberfläche eines Straßenquerschnitts. Die Einflussgrößen sowie deren Abhängigkeiten untereinander werden diskutiert und Potenziale für Maßnahmen zur Geschwindigkeitsreduzierung aufgezeigt. Im zweiten Teil der Arbeit werden für Tempo-50-Straßen verallgemeinerte lineare Modelle zur Beschreibung des Einflusses der Geschwindigkeit auf die Verkehrssicherheit abgeleitet. Für unterschiedliche Unfallkollektive bezüglich räumlicher Abgrenzung, Unfallschwere und Verkehrsbeteiligung wird der Geschwindigkeitseinfluss auf die Unfallzahl anhand einer Potenzfunktion (Power-Modell) unter Kontrolle der Randbedingungen Verkehrsaufkommen des motorisierten Individual-verkehrs und Umfeldnutzung beschrieben. Die Zahl der Unfälle mit Personenschaden steigt progressiv mit der mittleren Geschwindigkeit und degressiv mit dem DTV an. / Driving speeds of personal vehicles on urban roads are analyzed and their influence on traffic safety is modeled. The speed data is measured at cross sections on major and minor roads with speed limits of 50 and 30 km/h. Different kinds of classification of free-flow-vehicles were analyzed for the description of the desired speed of a driver. Also local speeds along road sections as well as time variation curves of driving speeds are documented in order to interpret and classify the provided findings. The first part of this work deals with the prediction of local driving speeds based on parameters of the roadway environment determining road design as well as the land-use next to the road. One first simple approach is to compare both driving directions at non-symmetric cross sections. Then several multiple regression models for mean speeds and 85-percentiles of the speed distribution are estimated and compared with each other. The models are based on the road network of the city of Dresden and are validated with speed measurements in other German cities. Road classification, cross section characteristics, land-use and the road surface condition are found to be significant parameters that correlate with driving speed. The possible influences on the choice of speed and their interdependencies as well as their practical relevance are discussed. In the second part of this work the influence of speeds on the occurrence of traffic accidents is estimated using Generalized Linear Models. This is done for different accident groups under consideration of the annual daily traffic and a parameter that describes the length and type of land-use of the adjacent buildings next to the road section. The relationship between speed and accident counts can be described using a power function. Accident numbers rise progressively with increasing speeds and rise in a declining manner with increasing amount of traffic.