Cover for rigiduct in driveway

[WWilts]

100mm black rigiduct being installed across driveway (occasional lorries). Rainwater drainage.

How to reduce risk of crushing?

 

Current plan: dig trench 200mm deep, cover with 100mm backfill of type 1.

For bed, would pea shingle or lean mix help?

For cover would concrete help?
 

 

[Conor]

I'd encase the whole thing in lean mix concrete. 100mm type 1 on top isn't near enough.