Not all rock needs to be larger than 75mm x 75mm mesh size
30% of most railway ballast specifications is between 50mm and 80mm rock size
The remaining 70% is between 30mm and 50mm size
The rocks in this image are all from the same pile of ballast, the lighter outer rocks are dry, hence the different colour
Railway ballast as delivered
The larger rocks need to be hand stacked at the face of the gabion, and the smaller rocks placed in the inside,
When using railway ballast as a landscape gabion fill, it may take longer to fill the gabions
Machine filling gabions with railway ballast is unlikely to be an option, as you need to sort the rocks for size.
Completed 450mm cube gabion filled with railway ballast.
The quarry silt has been washed from the rocks
Railway ballast is readily available, and often a lower cost option than standard gabion fill.
Making it suitable for filling landscape gabions, retaining walls should still be filled with the correct gabion rock specification, to ensure that the drainage and stability aspects are not compromised.
Gabion fill shall be hard, heavy, free draining and durable. A non frost susceptible (rock or stone type)
Gabion rock fill weighs approx 1700kgs per m3.
Before ordering railway ballast as a gabion fill check the size specification of the ballast. To ensure that 30% of the ballast rocks are greater than 50mm in size.