redrover

Aloha,
Have a pier on a bank that is falling away I need to add support to.
Home is above ground with ¾ on rocky soil bank. The remaining 1/3rd (behind me taking photo) the bank was cut out and remainder foundation is cement slab bottom floor, open basement you might call it I guess.
This is not a water problem, water never in there, no cold in the tropics. I think the general ground is stable, the entire lot is on a bank and there was no damage in the last severe earthquake. (Ever seen your main ceiling beam moving 2' from center side to side like Godzilla was straddling the roof and slapping the house?)

This pier is directly in front of the only access to under the house and via the lower floor, I'm taking the photo lying on the floor from the doorway. House is 25+ old and the bank is sliding down from scrambling up it to access under the house. (It was me doing the scrambling J in the last 10 years or so.)

The photo makes the problem look worse than it was and there is no upper floor sag. It was only a corner hanging in the open before. I've begun to dig out to make to ground in front more level and stopped when the bank crumbled as it is now. The big rocks you see in front I dug out. The rock pile behind it is what I've been tossing up there for years (from the scrambling.) I've been planning to do something to support the bank for this pier for some time.

Now I'm going to I find I really don't know what would be a good way. What or how should I go about that exactly. I've got ideas and done some searching but not finding this sort of situation anywhere.
Could I dig a bit deeper and wider, lay down concrete block and fill w/cement and rebar? Should I build a form like steps sort of? Can I gather the largest rocks I can carry and put them in the bottom?
Is there a better way I can do it? Is there a resource book for this you know of that I just can't find? I've exhausted my local supply and not finding a dang thing.
Mahalo for your time.

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