Best way to concrete large rock in place

[MrTint]

I was hoping I could get advise on how to concrete my rocks on my waterfall. They are large enough that I will be using a excavator to set the rocks. Some are super round and huge. I did see a huge fall done this way (I’ll post some pics of that) and I was told they put concrete in the gaps then put a colored mortar over the concrete to match the surrounding colors
Has anyone done this? How? I would like to do this to make it stable. Live in California so we get a occasional earthquake and would rather not have the boulders come rolling down the bank. Or if soul settles I guess that would cause it too.
First 2 pictures are from the waterfall I saw with concrete
The last 3 are pictures of my build. Sump, rock and excavation

 

[sissy]

Why do you feel you need to concrete them .Nice house looks almost like a Colorado house .

 

[MrTint]

Why do you feel you need to concrete them .Nice house looks almost like a Colorado house .

That’s acually a good friends house. He had his fall professionally done and they cemented all the rock in that fall

I thought it would make the rock stable and keep it from tumbling if ground shifted in any way. Also thought it would help redirect water over the spill ways along with foam

 

[mgmine]

I would use grout. Not the type you put in tile, the type that is used for heavy loads

 

[MrTint]

I would use grout. Not the type you put in tile, the type that is used for heavy loads

I didn’t know they had different types. I will check into that
I am pretty sure on my friends they did cement then colored grout or mortar to hide concrete and blend in with stone. Not sure if it was done that way to save on cost or easier. I’m sure mixing color into cement can be a challenge to match over multiple batches

 

[sissy]

you can get dye for cement also .I know grout they use to motor brinks in comes in lots of colors .Have you asked Erik the ponddigger or even the pondhuunter on youtube .You can google it my cousin and her family own a cement company in Indiana

 

[MrTint]

you can get dye for cement also .I know grout they use to motor brinks in comes in lots of colors .Have you asked Erik the ponddigger or even the pondhuunter on youtube .You can google it my cousin and her family own a cement company in Indiana

Thanks sissy. I have googled and YouTube the heck out of it. Nothing really shows that part of the build other than saying is was done. Tons of videos on how to mix the cement and consistency. Watched a ton of pond guy videos and pond digger but never thought to ask a question thru you tube. Duh thank you

 

[MrTint]

Going to start a new thread showing waterfall build but have one more question in regards to mortar.
Dose mortar act the same way as black foam? I found someone to mortar all my rock in place but not sure if I should have him do back of spillways. I know mortar is not waterproof but will it forces water over the top of the falls?

 

[GBBUDD]

Going to start a new thread showing waterfall build but have one more question in regards to mortar.
Dose mortar act the same way as black foam? I found someone to mortar all my rock in place but not sure if I should have him do back of spillways. I know mortar is not waterproof but will it forces water over the top of the falls?

I know mortar is not waterproof but will it forces water over the top of the falls??? will filling in the gaps change the flow rate to where it could over flow the liner? Sure it would depend how much flow is stopped and how much flow your channels can hold.

Grout is expensive It's a great choice for placing under large boulders as that is what grout is designed for to fill gaps between heavy objects such as under steel girders. An other alternative is to add Portland cement to your Mortar this will make the mortar much stickier and trying to do large boulders your probably going to have to do what's called a dry set. Google it. as far as the die Theres a couple ways to do it one is with a powder that turns the concrete a uniform color black brown redish orange gray etc and then there is acid washing pond digger acid wash >