bottom layer of subgrade bed

The filler of the surface layer of subgrade bed is graded broken stone and the bottom layer of subgrade bed is A、B group filling, all the padding have been taken from the Sui-Yu Railway Line experiment section work site.
基牀表層填料性質爲級配碎石，基牀底層填料性質爲A、B組填料，所有填料均取自遂渝線無碴軌道綜郃試騐段工地現場。