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20

The article refers to the northbound Zhuozhou Toll Gate at the G4 motorway just south of the Beijing city boundary. As you can see on the aerial photography from Google Maps, at this location, the G4 motorway has 8 lanes (4 in each direction): https://www.google.de/maps/@39.5485894,116.0341314,675m/data=!3m1!1e3


18

It is true, but in a very unspectacular way. The official traffic laws state: 10. The driver is prohibited to: ... 10.3 participate in road traffic on a vehicle covered with dirt (laminations), limiting the driver's field of vision and also making indiscernible the information on the registration plate at a distance of 40 meters and less So - ...


16

Germany is an interesting case to study this, as they have stretches of highway with and without speed limits. In a study done in the state of Brandenburg, the effect of putting a speed limit on stretches of highway has been studied by comparing the accident statistics before and after the new limit. On two stretches the speed limit was changed from no ...


14

There are several separate concepts to be addressed: fuel-efficiency, accident rate, fatality rate and experience in other countries. Does vehicle speed affect the fuel-efficiency? Fuel efficiency is measured in mpg or Litres/100 km - i.e. factoring out the speed travelled, and just looking at the distance you can get per volume of fuel. I am assuming that ...


12

This is a near-miss answer: it addresses only 60 km/h roads, not highways. Nonetheless, it addresses some of the attitudes to driving described in the question, so it may shed some light on the answer: For 60 km/h speed-limits: Driving faster than the speed limit is associated with a huge increase in the chance of being involved in an accident involving a ...


10

There is some evidence to suggest that increasing yellow light timing creates fewer accidents. Here (PDF) is a study on yellow light timing. They measured the number of red light violations at six intersections in Philadelphia, Pennsylvania over the course of a year, before and after increasing the yellow light duration by one second. Here are a couple ...


7

Safety I am going to answer with basic physics here: K = ½ m × v2 A 1200 Kg car moving at 30 m/s (~70 mph), has a kinetic energy of K = ½ 1200 Kg × (30 m/s)2 ≅ 500 KJ A 1200 Kg car moving at 35 m/s (~80 mph), has a kinetic energy of K = ½ 1200 Kg × (35 m/s)2 ≅ 750 KJ Therefore, increasing the limit from ...


7

I know this is long since solved, but I was looking into it a bit. If you consider an overhead image of the area that was jammed: http://a.abcnews.com/images/International/RT_beijing_traffic_1_jt_151008_4x3_992.jpg You can see that there is far more than 1 car per lane in the plaza. In fact I'm counting 50 cars across which may be where that number came ...


5

The two quotes say subtly different things. The second quote is much harder to examine, because talking about changes in speed limits without any information on compliance levels is useless. So I'll tackle the first quote, that risk of fatality halves when vehicle speed is 11.2 m/s (25mph, 40km/h) instead of 13.4 m/s (30mph, 48km/h). And that's true, at ...


4

Yes, faster speeds will increase accidents, but not by much if they are restricted to motorways A BMJ editorial has now joined this debate with arguments similar to those described in the first two answers given above. It concludes: Any potential economic benefit is likely to be outweighed by the adverse effects on health The key evidence it uses is ...


3

It may be difficult to answer this question using statistics. For example, the abstract to the article which rob cites in his answer says, The most frequent accident type among collisions between cyclists and cars at bicycle crossings was a driver turning right and a bicycle coming from the driver's right along a cycle track. This type of accident may be ...


3

The numbers are, broadly speaking, consistent. The lower number of pedestrian deaths reported for 2013, were from Jan and Feb 2014: that's when you'd expect that number to be provisional, and to under-estimate the total. As 2014 progressed, better data and late returns would have been compiled, leading to a rise in the numbers. So the 183 is probably about ...


2

Having taken a bicycle safety course, I can attest to part of the syllabus in which they explain why bicycle lanes are less safe than operating as another road user / vehicle operator. As a proponent of these courses, I operated in that manner and have personal experience for both methods. Bicycle lanes are unsafe compared to conventional road operations. ...


2

Not much research has been done into this topic, although the statistics published in the State of Idaho Highway Safety Plan, Fiscal Years 1981-1984 where used in an open letter by Jason N. Meggs to argue the following point: There is no evidence of any long-term change in injury or fatality rates as a result of the adoption of the original Idaho Law in ...


1

Here is a study made on the effectiveness of HOV Lanes. Essentially, the study says that: 1. Speed of traffic in a pool lane is reduced by 20% compared to off peak hours. 2. It increases congestion in other lanes, and reduces the speed in those lanes. 3. People who have long term pooling arrangements are not influenced by the time saving factor


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