|
There is a theory that it is only the tree roots that are holding together the embankments and cutting sides, especially in clay soils.
It's all to with the rate that the water drains through clay. It takes about 150 years for the water locked deep inside the clay to fully drain out. The dry soil is weaker than the damp soil. And when were many railway embankments and cuttings dug?.........About 1850 ish.
|