Back under the first edition rules, if you were trapped in a cage, or behind a portcullis, you knew what to do. With your best Incredible Hulk yell, you rolled percentile dice to see if you could make your "bend bars / lift gates" percent. Based on Strength, there was a straight -- albeit small -- chance to wrench those bars out of your way. Strength 8 gave you a 1% chance; that rose to 10% by Str 16.
And if you wanted to force one of those "stuck" dungeon doors? Roll a d6, and hope for a low number. Strength 8 let you open that door on a 1-2; Str 16 on a 1-3.
(Note how the game has improved since then. Two different arbitrary mechanisms for feats of strength, and no way to account for thin bars or thick, wood doors or iron, easy tasks or difficult ones.)
But now, what is the poor trapped Third Edition character to do? There are certainly rules -- more logical rules -- for breaking things in 3E, if you look for them. Monte Cook (the father of third edition) says, "Rules? We don't need no stinkin' rules!" (I'm paraphrasing here.)
Of course, the Internets have something for everybody. Here is a conversation about lifting a portcullis. And here are some thoughts on castle security.
But the best answer to all your breaking needs, I think, is a brand-new skill that does just what you need.
Check: Use Break for raw feats of strength, especially breaking things, forcing things open, bending and bursting. You can smash manacles and other bonds, push open stuck or locked doors, and even break through grates, doors, and walls. You can also use Break to entertain an audience as though you were using the Perform skill. In such a case, your “strongman act” consists of breaking through boards and bricks with your bare hands, feet, and head, as well as lifting heavy objects. This skill is a class skill for barbarians and monks.
Action: It is a standard action to attempt to break something.
Special: If an item has lost half or more of its hit points, the DC to break it drops by 2. Larger and smaller creatures get size bonuses and size penalties on Break checks: Fine -16, Diminutive -12, Tiny -8, Small -4, Large +4, Huge +8, Gargantuan +12, Colossal +16. If a tool such as a crowbar or ram is used, it gives a +2 circumstance bonus on Break checks.
Synergy: If you have 5 or more ranks in Break, you get a +2 bonus on Sunder special attack rolls.
||Break down simple door
||Break down good door
||Break down strong door
||Burst rope bonds
||Bend iron bars
||Break down barred door
||Burst chain bonds
||Break down iron door
||Break through 6 in thick wood wall
||Break through 3 in thick iron wall
||Break through 1 ft thick masonry wall
||Break through 1 ft thick reinforced masonry wall
||Break through 3 ft thick hewn stone wall
Okay! Now get out there and start breaking stuff!