Ferrocement! Why not?

Spraying grout is a common procedure. Check out Spraycrete. There are other similar methods, but it is ferrocement.
Spraycrete USA http://www.spraycreteusa.com/

 

Cement will contract and expand with a 15 degree temp. change, non shrink grout is just that, non shrink. Gonzo is on the money with the grout option , it should already be 7000 psi to 10000 psi or greater if you want to spend the money . The problem with grout can be set time .

 

The shrink that they are talking about is during solidification, not thermal expansion. An exact 15 degree temperature change can only be correct if you know the exact chemistry, temperature of the mix, the thickness, the ambient temperature etc. Exotherm is not a problem under ordinary circumstances, where 15 degrees is probably a reasonable rule of thumb. Large masses of concrete are often cooled with embedded water pipes because the heat cannot escape due to the surface are to volume ratio. I ran into it at Complex 39 at KSC. Decades after the fact, not during constriction. Look up Hoover dam.

10000 psi compressive strength is possible, so is 30,000, but you are looking at specialty products and most likely higher cost and limited availability and large minimum orders. When you start looking for tensile strength, very few claims are ever made. Of course concrete has some tensile strength. I can show you a freshly quenched piece of steel with a tensile strength of 300,000 psi and the impact resistance of glass. Tensile strength in concrete is probably only dependable with fiber reinforcement. It is moot to me. I have one retaining wall to look at and will never consider ferrocement

Gonzo, we may be comparing different products, wall coating and horizontal surface coating. I understand working with chopped fibers, I have used them and used extruded as well as injection molded long fiber thermoplastics. FFiber orientation and flow are a major issue.

 

15 degrees is rule of thumb . We needed to barge concrete 45 min. down a river on a bridge job for a large cap that needed a very slow set time , no cooling pipes . The concrete had to stay plastic from the batch plant to our barge , give us time to pour out 3 trucks once down river , a return trip to pick up 3 more trucks , get them down river , and have no cold joint in our cap. The Fed,s oked the Master Set and we had to come up with a mix with us and the concrete contractor having never used the product before . On the 1st test batch of a 5000 psi mix I left thumb indention,s in the concrete in my test cylinder,s after 3 days , a 7 day break was 11k psi . Different admixtures have reduced the cost of a high strength concrete and give many more options on a concrete mix today .