TRL cycle safety trials examine new junction and lane designs

Low-level signals: on test

Low-level signals: on test

Transport for London and TRL are trialling a range of cycle safety features on the test track at TRL’s Berkshire headquarters.

Volunteers are testing the features, which, if deemed successful, could be trialled on London’s roads next year. Measures include new ways of segregating cycle lanes; changes to traffic signals; revisions to junctions and roundabouts; and bus stop ‘bypasses’. A summary of each trial is given below.

Future trials will test different road markings used across Europe to see if they could have benefits for the UK’s roads.

Segregated cycle lanes: TRL says these can provide a safe route for cyclists without taking space from pedestrians. But physically segregated lanes can present problems for vehicles turning in and out of side roads and can also make it more difficult for cyclists to turn right.

The trials are investigating issues including:

• how far before a junction should physical segregation within a carriageway end?

• what road markings should be used to continue cycle lanes past a side-road turning?

• different methods for separating cycle lanes from other traffic, including continuous segregation by kerbs and hard margins, intermittent separation with bollards and reflective markers, or lines only

Dutch-style roundabout: Large roundabouts can be intimidating to cyclists, TRL points out. “Typical Dutch-style roundabouts have a tighter geometry that reduces vehicles’ speeds and improves visibility. Some also have an outer cycle lane that allows cyclists to travel around the roundabout separately to other traffic.”

TRL has constructed a purpose-built “Dutch-style” roundabout and is recording data on matters such as driver compliance with Give Way markings and traffic capacity, as well as people’s comprehension of layouts and markings. TRL will also compare this layout with that of signalised junctions (see below).

Low-level cycle signals: These provide signals closer to a cyclist’s eye level. They could display separate signal phases for cyclists.

High-level cycle signals:  Current UK regulations allow the use of a bicycle logo for green and amber signals but the logo cannot be used on the red lamp. TfL believes this creates confusion for road users if separate signal phases are given to cyclists and general traffic. “If you had a cyclist logo on a red light you could completely differentiate it [the signal] for cyclists,” a spokesman told LTT.

Ways of turning right at signalised junctions: Cyclists can face difficulty undertaking right turns because they have to cross traffic lanes and sometimes get caught between opposing streams of traffic. The trials will test:

•  A fully segregated signalised junction – Cyclists would turn right from a segregated cycle track. The movement could be undertaken in either a single movement or in two stages.

• Two-stage right turn – Where cyclists are mixed with traffic, the right turn could be carried out in two stages with a dedicated area provided for cyclists to wait after the first stage.

The performance of these junctions will be compared with the Dutch-style roundabout.

Bus stop islands: TfL plans to build cycle lanes round the back of bus stops, enabling cyclists to pass stationary buses without having to enter traffic lanes (LTT 21 Dec 12). The trials will test the best configuration to minimise conflict between cyclists and pedestrians crossing between the main footway and the bus stop island. Different layouts will be tested under different levels of pedestrian and cyclist flows “taking particular account of pedestrians with impaired vision or mobility”.

RFID tags: A large proportion of goods vehicles involved in fatal accidents with cyclists on London’s roads were turning left. Vehicle drivers are unable to see cyclists in the blind spot down the side of the vehicle and immediately in front.

TRL is therefore reviewing the possibility of an RFID (radio frequency identification) solution whereby bicycles would be fitted with an RFID tag. Goods vehicles would be fitted with a detection system that provides the driver with a warning if cyclists are in blind spot areas. TRL will ascertain whether suitable products exist or are near market, and may trial potential products.