Evaluation of the C-roundabout


Book Description

The C-roundabout (cyclist roundabout) is a new multi-lane roundabout design (developed as part of a 2006 Land Transport NZ research project Improved multi-lane roundabout designs for cyclists) that aims to improve the safety of cyclists at multi-lane roundabouts and make multi-lane roundabouts more cyclist-friendly. A C-roundabout was installed at the Palomino Dr/Sturges Rd intersection in Auckland and was evaluated between 2008 and 2011 in terms of its safety, capacity, and the opinions of cyclists, pedestrians and car drivers. The C-roundabout successfully reduced vehicle speeds to 30km/hr, which is close to the speed of cyclists. This made the roundabout safer for cyclists, as well as for other road users. The installation of the C-roundabout at this uncongested site had little impact on capacity. It drew positive feedback from cyclists and pedestrians, but about half of the car drivers were not in favour of it. This could be expected as they may prefer a wider roundabout than the narrow C-roundabout. Another site (Margan Ave/Hutchinson Ave) was also reviewed and involved changing two approaches from wide single lanes to two narrow lanes, without altering the kerbs and with no reduction in design speed. The evaluation showed the capacity of a single-lane roundabout can be improved (almost doubled) at very low cost. However, the safety of the roundabout had decreased and a reduction in design speed was recommended to address this.




Improved Multi-lane Roundabout Designs for Urban Areas


Book Description

This research, undertaken 2008 to 2010, investigated the comparative safety of multi lane roundabouts versus signalized intersections, pedestrian facilities, vertical deflection devices and visibility to the right. Guidance for practical application of the relevant measures to enhance roundabout safety has been developed and is included in this document. The Dutch turbo roundabout was reviewed and considered to be feasible for application in New Zealand. For intersections with four arms or more, a well designed multi lane roundabout should be significantly safer for vehicle users than traffic signals. Several means of adequately catering for pedestrians and cyclists at multi lane roundabouts are feasible to implement in many cases. In the interest of road safety, a Roundabouts First policy is recommended for adoption by the NZTA. The legal use of flashing signal displays and part time signal operation are also recommended for consideration, which would potentially allow for Pelican type pedestrian crossing installations, and also for signalized roundabouts to operate with less vehicle delay during off peak periods.




Alternative Types of Roundabouts


Book Description

This book presents a history of roundabouts, an introduction to their design, calculations of their capacity and traffic-safety features. It describes the key features of standard roundabouts and their limitations. Alternative types of roundabouts are a fairly recent development and have only been implemented in a few countries to date. The book illustrates a broad variety of these recent alternative types of roundabouts, as well as proposed types still in the development phase, explaining for each the specific needs it meets, its advantages and drawbacks. In closing, the book offers an outlook on the role of roundabouts in future street traffic.




Roundabouts


Book Description

TRB's National Cooperative Highway Research Program (NCHRP) Report 672: Roundabouts: An Informational Guide - Second Edition explores the planning, design, construction, maintenance, and operation of roundabouts. The report also addresses issues that may be useful in helping to explain the trade-offs associated with roundabouts. This report updates the U.S. Federal Highway Administration's Roundabouts: An Informational Guide, based on experience gained in the United States since that guide was published in 2000.




Roundabout Geometric Design Guidance


Book Description

This research report is intended to examine the geometric standards, guidelines, and practices used nationally and by other states to develop recommendations on roundabout design guidance for California. This research serves as a guidance tool in support of Caltrans policy and standards within the Highway Design Manual and other statewide documents. Recommendations made from this research will guide Caltrans and other agencies in California in designing and operating roundabouts. Several major areas were examined through this project, including assessing the operational performance of California roundabouts and developing calibrated capacity models consistent with recent national research (NCHRP 3-65); developing a calibrated intersection sight distance model; examining pedestrian and bicycle behavior at existing California roundabouts and comparing their performance to national observations; and developing a range of recommendations on geometric design parameters, including vehicle speeds, design vehicle, inscribed circle diameter, and issues related to roundabouts with more than four legs, roundabouts at freeway interchange terminals, and roundabouts in high-speed environments. The research resulted in a number of recommendations regarding the fundamental principles behind these elements, illustrated by tables and figures.




Urban Bikeway Design Guide, Second Edition


Book Description

NACTO's Urban Bikeway Design Guide quickly emerged as the preeminent resource for designing safe, protected bikeways in cities across the United States. It has been completely re-designed with an even more accessible layout. The Guide offers updated graphic profiles for all of its bicycle facilities, a subsection on bicycle boulevard planning and design, and a survey of materials used for green color in bikeways. The Guide continues to build upon the fast-changing state of the practice at the local level. It responds to and accelerates innovative street design and practice around the nation.







Recent Roadway Geometric Design Research for Improved Safety and Operations


Book Description

RB’s National Cooperative Highway Research Program (NCHRP) Synthesis 432: Recent Roadway Geometric Design Research for Improved Safety and Operations reviews and summarizes roadway geometric design literature completed and published from 2001 through early 2011, particularly research that identified impacts on safety and operations.




Cyclecraft


Book Description

Cyclecraft provides a guide to safe cycling both for adults and children. It contains practical advice on how to ride a bike confidently and safely in modern traffic conditions; The following areas are covered, including: how to get started; choosing a bike; basic skills; sharing the road with other traffic; advanced techniques for cycling safety on busier roads and faster traffic; advice on carrying children and goods and riding with others.