I've had a fair amount of utility knife experience, which includes a lot of field experience both military and civilian, and have always been captivated by the genre', finding the concept of the "unbreakable", rugged knife a siren's song...luckily, a song that doesn't lead to destruction, so long as you keep a few common sense ideas in mind....first, you don't have to spend a fortune for quality....second, LARGE heavy knives get heavier every step and will quickly get to the point you hate to put the thing on in the morning, and might even endanger your health and your trip if you have to evacuate out due to infection from blistering chafing from a weight not carried properly....thirdly, the key to avoiding the second point is proper load bearing, and I recommend lashing the knife to your pack and/or straps, and if you belt carry, get a wide, stiff sturdy belt to minimize chafing....quite a few good blades out there, most of which will split firewood when using another piece of wood on the spine,.... don't attempt this with skinning type knives with thin delicate edges, but don't get something so massively thick you can't slice with it (foodstuff, for instance, although I recommend a smaller sharp knife reserved for all fine/slicing chores)....recommendations? So very many mentioned already, and since I am not a Top-40-BS kinda guy, many of those I have never heard of, being a middle-aged crusty sort set in my ways...from personal experience, a shorter Himalayan Imports Ang Khola is a fine chopper/hacker/whacker utility blade that can still fashion a makeshft tent peg or pole, while being nearly unbreakable...I would recommend something like a CS Trailmaster/Recon-Scout except the handles chafe and come loose, the SRK is too short for chopping without blistering you badly in short order (and also has the same handle material), but the blades are good and tough....Ka-Bar (and their ilk) is a good all-around knife but fragile for abusive stuff (prying), and I recommend cutting off the top guard to get your thumb out on the spine for better control....most impressive to me is the Busse/Swamprat line, the economy Swamprat offering incredible performance for the money backed by a lifetime unlimited warranty against any and all use/abuse...you would want to try out the handles beforehand to make sure they work for you, as I think slicker handles work best for heavy work blades to prevent blistering....avoid any handle with an aggressive finish of any sort, also softer tacky synthetics...also, stay away from racy-looking knives with sharp hard edges except on the cutting edge, likewise sharp thumb-ridges on the spine, as they will all eat your hand alive with hard use (so this latter injunction will eliminate 90% of the hype/tactical knives out there...besides, tactical means strategic, and I have yet to hear of a knife so glorious you could conquer the world with just one, likewise the handguns, carbines, and tactical underwear...if it says "tactical", don't buy it, as they clearly don't even understand the English language so their gear is immediately suspect)....a tapered diamond sharpener that stows in its handle is the way to go for maintenance in the field, and keep in mind no stainless or near-stainless can resist shock or prying the way a carbon tool/spring steel can, but that also means edge rust which swiftly degrades an edge, so use a sheath that doesn't absorb/hold water....personally, I have a Mission MPK Ti blade currently as an all-around smaller field knife, as it may lack some in really sharp edge holding, but it is VERY abrasion resistant so holds a useful edge, sharpens easily with a finer sharpener, is near unbreakable and is totally maintenance free...but for general field use, I have a handforged large camp knife by an ABS Mastersmith made from 5160 spring steel...you can get a blade like that for less than many of the Top-40-BS knives seem to be going for, especially if you go with a Journeyman shooting for his Master rating (the Master being dependent on his making a damascus blade that equals his Journeymans carbon-steel blade)......in any case, have fun shopping, enjoy the hike, keep your feet dry and blister-free, and don't say I didn't tell you so....
