I doubt this is going to solve your problem, because:
- the government could react by banning the IP address as soon as they have identified your site
- even if you are the only one using that IP address right now, and your activities do not directly penalize other clients that share the same IP address, the webhost could ask you to take your business elsewhere, because an IP address that is blacklisted becomes less usable - it's the same problem with spammers: they cause their IP address ranges to be blacklisted and for this reason they are seldom welcome
- if the government in question has equipment sophisticated enough they may be using DPI which means they can selectively filter Internet access, based on URL or page contents, meaning: banning domain names is not the only thing they can do
Probably the best you can do is rotate domain names often (like torrent sites), or move to Tor perhaps, but only a minority of people visit Tor and it would not be surprising it is censored as well.
It's possible that the censorship is rudimentary, for example some countries block torrent sites at DNS level and ISPs simply redirect or block requests for banned domain names.
But many people use public DNS like Google's or OpenDNS and are thus able to easily bypass the censorship (without even realizing it).
Without knowing the country in question it's hard to comment further.