Maybe temporary foundations for something?Three pictures from Huddersfield today. First one showing longitudinal timber baulks between platforms 1 &4.
Second shows yellow spray painted line from end of platform 6 to beginning of platform 1. Line actually extends beyond platform 8 to boundary road ght across all tracks. It looks like where the existing platforms etc will eventually be cut off to remodel Leeds end throat.
A decade (or so) ago there were major on-platform works at Stockport. During the week an area was filled with stacked expanded polystyrene blocks about 1m x 1.5m x 2 m. I think they were laid across the tracks during weekend posessions so that plant could drive from platfrm to platform...