{"id":6298,"date":"2023-09-01T13:51:28","date_gmt":"2023-09-01T12:51:28","guid":{"rendered":"https:\/\/trlsoftware.com\/?p=6298"},"modified":"2023-09-01T13:51:28","modified_gmt":"2023-09-01T12:51:28","slug":"rfc-output-in-lane-simulation-mode-junctions-10","status":"publish","type":"post","link":"https:\/\/trlsoftware.com\/2023\/09\/01\/rfc-output-in-lane-simulation-mode-junctions-10\/","title":{"rendered":"RFC output in Lane Simulation Mode \u2013 Junctions 10"},"content":{"rendered":"
Can anyone guess what the following documents have in common \u2013 \u201cTA 23\/81 \u2013 Junctions and Accesses: Determination of Size of Roundabouts and Major \/ Minor Junctions (1981)\u201d\u00a0\u00a0 ; TD16\/93 \u2013 Geometric design of roundabouts (1993)\u201d; \u00a0\u201cAG74 \u2013 Junctions 10 User Guide (2023)\u201d<\/em> – apart from all being related to UK unsignalled junction design?\u00a0 The answer is that somewhere within their text they all refer to the ratio of flow to capacity (RFC) and a specific threshold value related to assessing the acceptability (or not) of a UK junction design.<\/p>\n From the age, and also the age range<\/u> of these documents, you can see how long the ratio of flow to capacity has been used to evaluate junction performance and acceptability in the UK.\u00a0 It is an established method to check the model outputs to see if RFC is at or below 0.85, or 85% if you prefer.\u00a0 This is known across all of the UK, and well beyond to boot. \u00a0I won\u2019t try to defend its use here, nor will I try today to persuade you to use other traffic model parameters instead \u2013 these do<\/u> exist – but I also know how very attractive a \u2018black and white\u2019 answer is in a modelling world where such kinds of answers are rare indeed.<\/p>\n