Welcome!

As others have said, a normal bike is not going to collapse underneath you - it is long term durability that you need to be concerned about, and wheels are the most obvious weak point on most factory bikes -just about everyone on this forum has had wheels that began breaking spokes after very little riding.

I agree that something with a stout frame and a rigid fork - like maybe a Specialized hardrock or Kona Hoss with the suspension fork swapped out for a rigid one - will probably fit the bill. A bike shop can probably get you a hub and rim with 48 spokes to build a bombproof rear wheel. I reccomend also trading the stock knobby tires for lightly treaded road tires to make your riding more fun and rewarding.

Good luck!