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Highlights • Overtaking behaviour of motorized vehicles when passing bicycles on urban arterials was analyzed. • A methodology was developed to estimate the number of expected unsafe passing events on a given 4-lane urban arterial. • The methodology enables quantifying the risks imposed to cyclists while sharing the road with motorized vehicles. • Model inputs are bicycle demand, section length, AADT, speed limit, and upstream traffic signal configurations. Abstract In this study interactions between motorized vehicles and bicycles were studied by analyzing the overtaking behavior of motorized vehicles when passing bicycles on urban arterials. A methodology is presented to estimate the number of 'unsafe' passing events on 4-lane urban arterials with no on-street bike lanes. A 'critical passing distance' is defined to classify expected passing maneuvers i.e. when a motorized vehicle overtakes a bicycle, into 'safe' and 'unsafe' passing events. The proposed method enables calculation of the expected number of 'unsafe passing' events based on the expected bicycle demand, road segment's length, AADT, speed limit, and traffic signal timing parameters. The 'critical passing distance' is an input parameter and can be set by the planner. Given the number of expected 'unsafe passing' events, and institutional safety objectives and standards in terms of acceptable risk levels for cyclists, transportation planning departments can use the proposed methodology to decide whether provision of a specific cycling facility is necessary for a given road segment. [ABSTRACT FROM AUTHOR]

Highlights • We ask which bicycle lane types are associated with fewest crashes. • Spatial units of analysis were street segments and intersections. • Lowest crash odds found where there are higher speeds, tram stops, and bus routes. • Exclusive bicycle lanes reduced bicycle crashes in all these settings. • Kerbside bicycle lanes were the least beneficial bicycle lane type. Abstract Bicycle lanes reduce real and perceived risks for bicycle vs. motor vehicle crashes, reducing the burden of traffic injuries and contributing to greater cycling participation. Previous research indicates that the effectiveness of bicycle lanes differs according to roadway characteristics, and that bicycle lane types are differentially associated with reduced crash risks. The aim of this study is to combine these perspectives and identify the types of on-road bicycle lanes that are associated with the greatest reductions in bicycle crashes given the presence of specific roadway characteristics. We compiled a cross sectional spatial dataset consisting of 32,444 intersection polygons and 57,285 street segment polygons representing the roadway network for inner Melbourne, Australia. The dependent measure was a dichotomous indicator for any bicycle crash (2014–2017). Independent measures were bicycle lanes (exclusive bicycle lanes, shared bicycle and parking lanes, marked wide kerbside lanes, and kerbside bicycle lanes) and other roadway characteristics (speed limit, bus routes, tram routes, bridges, one-way flow, traffic lane width). In Bayesian conditional autoregressive logit models, bicycle lanes of all types were associated with decreased crash odds where speeds were greater, bus routes and tram stops were present, and traffic lanes were narrower. Only exclusive bicycle lanes were associated with reduced crash odds (compared to the expected odds given the presence of the bicycle lane and the roadway conditions) in all these setting. The extent to which on-road bicycle lanes reduce crash risks depends on the bicycle lane type, the roadway conditions, and the combination of these two factors. Bicycle lanes that provide greater separation between cyclists and vehicular traffic are most consistently protective. [ABSTRACT FROM AUTHOR]

In 2015, a controversial bicycle lane was installed on Paulista Avenue –a thoroughfare in the heart of the megacity of São Paulo with a high rate of motorised vehicles. For the first time, on-bicycle air pollution concentrations were assessed along this lane using black carbon (BC) as an indicator of fossil fuel combustion. We measured BC concentrations with a hand-held microaethalometer at a high temporal resolution, enabling the capture of fine spatial gradients along the route. Although this new link expanded the city's cycling network, our pioneering study showed that BC concentrations were large (mean 8.5 μg m −3 ) with extreme values reaching 24.0 μg m −3 , comparable to concentrations found in many megacities. In agreement with other studies, we observed that concentrations decreased about 1.6 times on a section of the bicycle lane running through a calmer neighbourhood, which could indicate the potential to safeguard the health of cyclists by installing lanes with greater separation from main roads, such as Paulista Avenue. This pilot work paves the way to more detailed studies aiming to map out the spatial distribution of other traffic-related pollutants across the city's 458-km long bicycle network. [ABSTRACT FROM AUTHOR]

In some circumstances on streets equipped with new bike facilities, cyclists are not interested in using them. Instead, they continue to use shared spaces with pedestrians or motor vehicles. Thus, simply adding a bike facility does not guarantee that cyclists will switch to using it. Owing to the considerable development of bike facilities, the investigation of facility preference, particularly focusing on facility choice forecast, has become increasingly important. This study developed a model for predicting the facility choice of cyclists between on-street facilities (curb, traffic lane, and bike lane (BL)) and off-street facilities (sidewalks). Initially, the optimal model was selected using Bayesian Model Averaging method. Then, it was validated by both internal and external validations. Apart from the aforementioned factors, several other exogenous variables were also found to be significant predictors of bike facility choice, including the width of traffic lanes, existence of real-time stopping vehicle, type of bike, bus stop existence, and in-group cycling. Analysis of the relative importance of predictors indicated that bus stop existence, effective sidewalk width, and type of bike were the potential predictors. A framework for predicting BL usage, if it is present, was also developed. A test for the predictive performance of the application at a real site was carried out. By comparing predicted and actual BL usage figures, the analysis showed good predictive performance. The results of this study can help developers, planners, and designers to adopt reasonable investment decisions as well as better designs in developing new bike facilities. [ABSTRACT FROM AUTHOR]

The primary objective of the study was to identify the factors that influenced the comfort perception of e-bike, e-scooter and bicycle riders in mid-block bicycle lanes on urban streets and to estimate the bicycle level of service (BLOS) of a mid-block bicycle lane with mixed two-wheeled traffic. Data were collected at thirty locations on thirty different streets in Nanjing area in China. Pearson’s Chi-square tests were conducted to make comparisons of the comfort perception among different cyclist groups. The factors that significantly affected the comfort perception of the cyclists included the age of the cyclists, the type of two-wheeled vehicles, the volume of two-wheeled vehicles, the width of mid-block bicycle lanes, the proportions of e-bikes and e-scooters in two-wheeled vehicles, the physical separation between motorized, bicycle and pedestrian lanes, the slope of bicycle lanes, the roadside access points and the roadside land use. Ordered probit models were developed to quantitatively evaluate the impacts of different contributing factors on the comfort perception of the riders of e-bikes, e-scooters and bicycles. The results showed that compared to the riders of bicycles, the riders of e-bikes and e-scooters were more likely to perceive a poor comfort level. The comfort perception of the cyclists increased with an increase in the width of the mid-block bicycle lane, whereas it decreased with an increase in the volume of two-wheeled vehicles. The proportions of e-bikes and e-scooters in two-wheeled vehicles negatively affected the comfort perception of the cyclists. In addition, the presence of physical separation between the motorized, bicycle and pedestrian lanes significantly increased the comfort perception of the cyclists. With the comfort perception models, a procedure was developed and insights were gained to help transportation professionals estimate the BLOS of a mid-block bicycle lane with mixed two-wheeled traffic. [ABSTRACT FROM AUTHOR]

In recent years, many bicycle lanes on urban streets are replaced with vehicle parking places. Spaces for bicycle riding are reduced, resulting in changes in bicycle and vehicle operational features. The objective of this study is to estimate the impacts of on-street parking on heterogeneous traffic operation on urban streets. A cellular automaton (CA) model is developed and calibrated to simulate bicycle lane-changing on streets with on-street parking. Two types of street segments with different bicycle lane width are considered. From the simulation, two types of conflicts between bicycles and vehicles are identified which are frictional conflicts and blocking conflicts. Factors affecting the frequency of conflicts are also identified. Based on the results, vehicle delay is estimated for various traffic situations considering the range of occupancy levels for on-street parking. Later, a numerical network example is analyzed to estimate the network impact of on-street parking on traffic assignment and operation. Findings of the study are helpful to policies and design regarding on-street vehicle parking to improve the efficiency of traffic operations. [ABSTRACT FROM AUTHOR]

The aim of this study was to describe the crash characteristics and patient outcomes of a sample of patients admitted to hospital following bicycle crashes. Injured cyclists were recruited from the two major trauma services for the state of Victoria, Australia. Enrolled cyclists completed a structured interview, and injury details and patient outcomes were extracted from the Victorian State Trauma Registry (VSTR) and the Victorian Orthopaedic Trauma Outcomes Registry (VOTOR). 186 cyclists consented to participate in the study. Crashes commonly occurred during daylight hours and in clear weather conditions. Two-thirds of crashes occurred on-road (69%) and were a combination of single cyclist-only events (56%) and multi-vehicle crashes (44%). Of the multi-vehicle crashes, a motor vehicle was the most common impact partner (72%) and distinct pre-crash directional interactions were observed between the cyclist and motor vehicle. Nearly a quarter of on-road crashes occurred when the cyclist was in a marked bicycle lane. Of the 31% of crashes that were not on-road, 28 (15%) occurred on bicycle paths and 29 (16%) occurred in other locations. Crashes on bicycle paths commonly occurred on shared bicycle and pedestrian paths (83%) and did not involve another person or vehicle. Other crash locations included mountain bike trails (39%), BMX parks (21%) and footpaths (18%). While differences in impact partners and crash characteristics were observed between crashes occurring on-road, on bicycle paths and in other locations, injury patterns and severity were similar. Most cyclists had returned to work at 6 months post-injury, however only a third of participants reported a complete functional recovery. Further research is required to develop targeted countermeasures to address the risk factors identified in this study. [ABSTRACT FROM AUTHOR]

The objectives of this manuscript are (1) to evaluate the effectiveness of on-street bicycle lane in reducing crashes involving bicyclists on urban roads, (2) to quantify and compare risk to bicyclists on road segments with and without on-street bicycle lane, (3) to evaluate the effect of on-street bicycle lane on other road network users (all crashes), and, (4) to assess the role of on-network characteristics (speed limit, the number of lanes, the width of on-street bicycle lane, the width of the right-most travel lane, and, the numbers of driveways, unsignalized approaches and signalized intersections per unit distance) on risk to bicyclists. Data for thirty-six segments with on-street bicycle lane and twenty-six segments without on-street bicycle lane in the city of Charlotte, North Carolina were extracted to compute and compare measures such as the number of bicycle crashes per center-lane mile, the number of bicycle crashes per annual million vehicle miles traveled (MVMT), the number of all crashes per center-lane mile, and the number of all crashes per MVMT. The results obtained from analysis indicate that bicyclists are three to four times at higher risk (based on traffic conditions) on segments without on-street bicycle lane than when compared to segments with on-street bicycle lane. An analysis conducted considering all crashes showed that on-street bicycle lanes do not have a statistically significant negative effect on overall safety. An increase in annual MVMT (exposure) and the number of signalized intersections per mile increases the number of bicycle crashes, while an increase in on-street bicycle lane width or right-most travel lane width (if on-street bicycle lane cannot be provided) decreases the number of bicycle crashes. Installing wider on-street bicycle lanes, limiting driveways to less than 50 per mile and unsignalized approaches to less than 10 per mile, increasing spacing between signalized intersections, and, facilitating wider right-most travel lane if on-street bicycle lane cannot be provided reduces occurrence of bicycle crashes and lowers risk to bicyclists on roads. [ABSTRACT FROM AUTHOR]

Abstract: After many years without any substantial improvement in bicycle infrastructure in Curitiba, a 4-km Leisure Bicycle Lane was implemented in the central area of the city in 2011. The project was one of several that City Hall hurriedly implemented following pressure from bike activists. On the Sunday the project was launched, more than three thousand cyclists are estimated to have used the bicycle lane; of these, 300 cycled alongside the lane, outside it, against it. They made the front pages of newspapers, disrupted the sociotechnical framework of bicycle policy in the city and put bicycles on the political agenda of the municipal elections. This paper discusses why, in a city renowned worldwide for its public transportation system and for having more than a 100km of bicycle lanes, a bicycle project failed after being sabotaged by cyclists and was definitively abandoned in February 2013. Based on interviews with key actors, including public officials, journalists, and bicycle activists, this paper concludes that the failed bicycle lane unveils the profound and urgent social and political dimensions embedded in what had been presented by municipal authorities as a neutral technical solution. [Copyright &y& Elsevier]

Abstract: Maryland (MD) recently became one of fourteen states in the United States to enact a traffic law requiring motor vehicles to pass bicyclists at a distance of greater than three feet. To our knowledge, motorist compliance with the law has never been assessed. This study measured the distance between overtaking motor vehicles and cyclists [e.g. vehicle passing distance (VPD)], to develop baseline metrics for tracking implementation of the three-foot passing law in Baltimore, MD and to assess risk factors for dangerous passes. During September and October 2011, cyclists (n =5) measured VPD using a previously published video technique (). Cyclists logged a total of 10.8h of video footage and 586 vehicle passes on 34 bicycle commuting trips. The average trip lasted 19.5±4.9min and cyclists were passed on average 17.2±11.8 times per trip. VPDs of three feet or less were common when cycling in standard lanes (17%; 78 of 451 passes) and lanes with a shared lane marking (e.g. sharrows) (23%; 11 of 47 passes). No passes of three feet or less occurred in bicycle lanes (0 of 88 passes). A multiple linear regression model was created, which explained 26% of the variability in VPD. Significant model variables were lane width, bicycle infrastructure, cyclist identity, and street identity. Interventions, such as driver education, signage, enforcement, and bicycle infrastructure changes are needed to influence driving behavior in Baltimore to increase motorist compliance with the three-foot law. [Copyright &y& Elsevier]

• Factors for bicycle crash are modeled by applying sGWPR. • LMC is used to assist the variable selection in sGWPR. • The effect of bicycle lane intersection density on bike crash varies across space. While cycling benefits individuals and society, cyclists are vulnerable road users, and their safety concerns arouse more macro-level spatial crash studies. Our study intends to investigate the spatial effects of population, land use, and bicycle lane infrastructures on bicycle crashes. This was done by developing a semi-parametric Geographically Weighted Poisson Regression (sGWPR) model which deals with the issue of spatial correlation and spatial non-stationarity simultaneously. It is a model that combines both constant and geographically varying parameters. To determine which parameter is fixed or non-stationary, previous studies suggest monitoring the Akaike Information Criterion (AICc). Yet, relying only on AICc might bury some spatial associations. So, in this study, we propose a Linear Model of Coregionalization (LMC) to assist the decision. Here, we use bicycle crash data across the metropolitan area of Greater Melbourne to establish sGWPR models suggested by AICc and LMC, respectively. Comparing the two sGWPR models, we found the sGWPR model under LMC results performs as well as sGWPR models suggested by AICc from the AICc perspective, and a 22.5% improvement in the mean squared error (MSE). It also uncovers more details about the spatial relationship between bicycle crashes and bicycle lane intersection density (BLID), an effect not suggested under AICc results. The parameters of BLID, a new measurement of bicycle lane facilities proposed by us, vary over space across analysis zones in Greater Melbourne. [ABSTRACT FROM AUTHOR]

New technologies are changing the sector of infrastructures design and construction. One of the most important is the I-BIM (Infrastructure Building Information Modelling), that is a management information system of digital processes for infrastructures. In this study the I-BIM approach has been used for the upgrade of a section of the SS 245 road, in the north of Italy, in order to show its benefits applied on existing road infrastructure. The project involved the design of a new road segment and its connection with the existing road network and with a railway line. These last were respectively solved by a roundabout and by a jacked tunnel under the railroad with wing walls at each exit side of the structure. The steps carried out in this study were modelling the 3D digital terrain model from point cloud; creating the horizontal alignment, vertical profiles and editing cross-sections; modelling the jacked tunnel; creating the roundabout; generating the 3D parametric model of the complete road and visualizing the infrastructure in the real-world context. The real innovation consists in the creation of a plugin that allows extrapolating directly from the design program to the compute one, all the features need to be calculated. The BIM tools used were "Autodesk AutoCAD Civil 3D" and "Revit Structure", used respectively for road geometrical design and for tunnel structural project. The obtained results have been showed that the I-BIM approach represents not only a powerful tool to optimize and validate the road project according to norms before its construction, but also to see how the infrastructure works with the 3D real environmental context. • The I-BIM approach has been used for the upgrade of a road to show its benefits applied on existing road infrastructure. • The project involved the design of a new road segment a roundabout, and a jacked tunnel. • The results have been showed that I-BIM approach represents a powerful tool to optimize a road project before construction. [ABSTRACT FROM AUTHOR]

• Bicycling rates increased across study sites regardless of the presence of a cycling facility. • A new cycling facility increased the odds of bicycling more on the street. • New facilities were associated with increased commute-related bicycling only for regular cyclists. • Mode-substitution was more likely near a new cycle track vs. a painted bicycle lane. • Urban vs. suburban location was associated with more cycling on street, but not with mode substitution. Cycling facilities have become a widely used sustainable transportation policy tool, but their impacts on reduced car dependence are difficult to isolate. This paper presents the findings from a household survey conducted in 17 neighbourhoods in the Toronto region, Canada, some with a recently built cycling facility and some without. Results indicate higher odds of increased commute-related bicycling on streets with a new cycling facility. People who were already commuting by bicycle at least once a week are likely to bicycle more frequently after new facilities are built. Bicycling uptake is more obvious in neighbourhhods with a new cycle track, while changes relating to bicycle lanes were not statistically different from neighbourhoods without a facility. All else being equal, urban cycling facilities were associated with higher odds of increased commute-related bicycling, compared to suburban locations. Findings offer insights into expected outcomes of bicycle network expansion policy/projects. [ABSTRACT FROM AUTHOR]