What is the device used to prevent vehicles from moving beyond the end of rails at terminals?

The device designed to prevent vehicles from moving beyond the end of rails at terminals is called buffer stops. Buffer stops are placed at the end of a railway track to absorb the impact of rolling stock and ensure that vehicles do not derail or overshoot the end of the track. They act as a safety measure, protecting both the train and the surrounding infrastructure from potential damage caused by a train coming to a halt too late.

Buffer stops come in various forms, including fixed or retractable structures, and are essential in terminal operations where trains are frequently stopped or started. Their design often includes features that can withstand considerable force, ensuring safety in busy rail environments.

The other options, while related to rail operations or concepts, do not serve the same purpose as buffer stops. For instance, turn-tables are used for changing the direction of trains, triangles refer to track layouts for rerouting, and scotch blocks are chocks used to secure stationary vehicles, but none are specifically designed to act as a terminus barrier to prevent movement beyond the end of rails.