No, ignorance doe's not make you exempt from the law. If the signs are visible and up to code, and you missed them. Now damages to you can be a different story, unless there are signs that say construction, enter at own risk, etc. Then you cannot do anything.
@SteveK is right on target. Just because someone puts up "warning signs" doesn't necessarily excuse them from liability arising from your use of their property. What if you don't understand English? Would that mean that only English-speaking victims were prohibited from suing them? Wouldn't make sense. They have the burden of proving the defense that you "voluntarily assumed the risks", which might limit your claim, but only to the extent the damage or injury arose from the risks of which you were actually aware.
In fact, under the laws of some states, even pointing out the disclaimer and warnings as an attempt to discourage you from filing a complaint would be considered "unfair and deceptive business practices" (a type of fraud), if they know (or should know) that your claim may be upheld in court.
But courts sometimes also have "common sense". If you're told to "watch out for the bricks", and you say, "okay, I got it", and then recklessly wander into the danger zone, that liability is on you, assuming you are an ordinarily prudent person and not mentally challenged, or the like.
Add: Some states have specific statutory immunity for landowners who allow visitors on their property, free of charge, for "recreational purposes", recognizing the inherent dangers and putting the entire burden upon the visitor to take steps for their own personal safety. Even these statutes, however, would not protect a landowner from liability arising from injuries caused by intentionally hurting the visitor. Raises good questions of whether a recreational visitor stepping into a hidden bear trap could sue for injuries. E.g., NH RSA 212:34, which has an exception for "willful or malicious failure to guard or warn against a dangerous condition, use, structure or activity;" Similar in RSA 508:14: "landowner shall not be liable for personal injury or property damage in the absence of intentionally caused injury or damage."