IPK was designed as a cover to put 45 cms of earth on top in an emergency. It is still taught and I haven't heard of it being withdrawn will put some feeders out to try and find out.
As for use in the Gulf wars, there is an earth hardness test with a cone penetration device, depending on the result lets you know what shelters can be built, or just use the heel of a boot. If the ground is too soft then above ground shelters, like sandbag bunkers would be used. If it was firmer then trenches okay, too hard then errrr . To prevent collapse in use or under bombardment the basic trench is reinforced. The trench sides can be shored with sheets of corrugated iron which are held in place with iron pickets that are held in place with wire pegged out. The roof is then made using more sheets of corrugated iron held on more iron pickets. Alternatively corrugated sheets with a curve at one end can be used and a roof made with that.
If you have these stores and better still the plant operators to put it in bonus, IPK not necessary. If none of the above and you expected someone to start shelling you in a bit then entrenching tool and magic nylon to the rescue. But the idea is that in modern war you are either mobile or Hesco bastion, sand filled cubes would be made into above ground shelters.
Will check up on IPK though.
