Tell us what kind of machine you want to put on there. Maybe we are using a sledgehammer to crack a nut here. Is there no detailed drawing of the machine that describes the necessary mounting?
Are you concerned about theft protection or storm protection?
Primarily, I want to prevent any hooligans from knocking over the machine. Someone who wants to steal the device will manage it even with the best security. However, such devices are more likely to be broken into than completely taken away.
Primarily, it's about preventing some punks from knocking over the machine. Anyone who wants to steal the device will manage to do so even with the best security. However, such devices are more likely to be broken open than completely stolen.
Then why don't you simply use screw-in ground anchors and secure the machine to them? That way, it can't be knocked over either. Just lay gravel under the machine as the base, and done.