Provision Of Cycling Facilities

chapter three

road sections
3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 3.1 0 Design tools Segregation or integration Possible cycle facilities along road sections Physical segregation Different means of physical segregation Contra-flow cycle tracks On-road cycle tracks Contra-flow on-road cycle tracks Carriageway width for mixed traffic use Cyclists and pedestrians only

Provision of CyclingFacilities | National Manual for Urban Areas

Segrated Cycle Facility and Exit Construction (Holland)

3.1 Design tools
3.1 .1 Space required for a cyclist - The width of the track surface is based on a deviation of 0.25m. This is standard for cycling speeds up to 11 km/hour. - The deviation path of a cyclist is at a minimum when the cycling speed is near to 20 km/hour. - When the cyclingspeed is less then 11km/hour more space for deviating must be provided. For example when cyclists are approaching

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traffic lights. - The length of a bicycle is 2.00m. - The width of a stopped cyclist is 0.75m. The minimum amount of space needed by cyclists in different situations is shown in figures 3.1 and 3.2.

Height restriction Figure 3.2 shows that the minimum headroomrequired for cyclists in subways, or under road signs, is 2.50m.

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Provision of Cycling Facilities | National Manual for Urban Areas

FIGURE 3.1 | PROFILE OF A CYCLIST

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Provision of Cycling Facilities | National Manual for Urban Areas

FIGURE 3.2 | THE MINIMUM AMOUNT OF SPACE NEEDED BY CYCLISTS IN DIFFERENT SITUATIONS

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Provision of CyclingFacilities | National Manual for Urban Areas

3.1 .2

Gradients (fig 3.3)

Descending: - roads should be designed so the descent speed of cyclists can be controlled, unless the gradient ends with a long level stretch. Areas of a level track should be used to assist cyclists to reduce their speed on a descent; - at the base of a gradient greater than 2% it is desirable to have a horizontalsection of at least 5m in advance of traffic lights or a junction. - sharp bends on, or at the base of a gradient, should be avoided; - necessary control devices should be placed on the gradient of slopes, to prevent cyclists building up high speeds. For example, the provision of 5m sections of level track at intervals is effective.

Ascending: - for short rises (height difference up to 10m) thelowest section can be designed with a steeper gradient after which the higher section should be designed with a flatter gradient. (see vertical alignment situation A). This helps the cyclist climb the gradient at a more constant speed; - for long gradients (height differences of more than 10m) after every climb of 5m height

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difference, a horizontal section of approximately 25mwill help to make the climb easier for cycle traffic (see vertical alignment situation B); - take into consideration the influence of the wind, and cover from vegetation.

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Provision of Cycling Facilities | National Manual for Urban Areas

FIGURE 3.3 | VERTICAL ALIGNMENT SITUATION A AND SITUATION B

Vertical alignment situation A

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Vertical alignment situation B

25Provision of Cycling Facilities | National Manual for Urban Areas

3.2 Segregation or integration?
The decision to segregate cycle traffic from motorised traffic depends on the speed and volume of the motor vehicles. The volume of cycle traffic determines the dimensions and the type of facilities. Figure 3.4 shows the result of an investigation conducted by SWOV (the Dutch Institute for RoadSafety Research). This figure can be used to obtain a rough estimation of the type of segregation needed in relation to different combinations of speed and volume. The lines in

- Area 3 In this area, mixed use of the road or on-road cycle tracks is acceptable. However, depending on other road and traffic features the provision of specific cycle facilities might still be preferable. - Area 4 A...