Subgrade peat stabilisation system for railway

A ground stabilisation system for a railway having rails supported across rail ties on a ballast layer over a subgrade region which includes a peat layer, the system comprising:

• a plurality of pipe assemblies inserted in an upright orientation within the peat layer of the subgrade region, each pipe assembly comprising:
• a pipe member formed of semi-rigid material and having a hollow interior;
• aggregate fill occupying the hollow interior of the pipe member;
• a tensile reinforcing member extending about the pipe member providing tensile reinforcement at least in a circumferential direction about the pipe member;
• and
• a plurality of openings in the pipe member which are arranged to allow communication of fluid from the peat layer surrounding the pipe member into the hollow interior of the pipe member so as to be arranged to reduce fluid pressure in the peat layer when the peat layer undergoes dynamic loading from a passing train;
• each pipe assembly having a stiffness in an axial direction which is greater than a dynamic stiffness of the peat layer so as to be arranged to reduce loading on the peat layer when the peat layer undergoes dynamic loading from a passing train.