// they haven´t got a hard shoulder //
not all "smart motorways" fall into that category. there are 3 types - Controlled Motorway, Dynamic Hard Shoulder and All Lane Running. All Lane Running does what it says on the tin and is what many understand to be "smart motorways". Dynamic Hard Shoulder was the prototype model for managed motorway where the shoulder could be used in times of congestion, the technology used to make it work was intensive and expensive to install and monitor, so it has seen little use. Controlled motorways have the gantries and cameras as for All Lane Running, but in areas where the road has been widened under narrow bridges, leading to non-continuous shoulders and therefore no chance for shoulder running.