Step one is take a deep breath, step away from the computer, and try to reconstruct whatever may have happened, specifically what things you did or have happened since the last time it worked.
That there were .lock files present indicates lightroom was not shut down properly last time.
Knowing how things went bad are the first step to trying to undo whatever happened.
Secondly, what backups do you have of the overall system and images (not catalog backups -- real backups, on another disk)?
Third, my suggestion is unless you know the cause, start with the assumption your disk drive is failing, and try to save what you can. That means making another backup of the drive (on a different disk, NOT overwriting any existing backups as you might need them). Drives, especially spinning media, often fail slowly enough you can save data from them before they fail completely, but there's a fair chance whatever you save is also corrupt.
Fourth (and in this order), I would suggest running the check disk tool in Windows on that drive and your system drive if different (explorer, properties, tools, check). That should give some indication whether the drive itself has become corrupt.
You need more data to really have a good path forward; these are how I would go about getting it. If some of these fail, consider doing a power cycle, but before you do go into Control Panel, Power Options, Define Power Button, and turn off "fast startup". Fast startup keeps the computer from doing a complete boot. Then shut down, power off, wait a bit, and power up and see if anything changed.
That you have multiple catalogs all showing corrupt could be that (a) the drive has major corruption and lots of things are now caput, (b) the drive is fine, the files are fine, but cannot be read and used properly [bug in lightroom or bad install, bad controller or other corruption in windows], (c) you corrupted the catalog long ago, but it did not notice, and it has been backing up corrupt data all along.
(c) seems a bit unlikely if you were using LR for the catalog backup since it closes and re-opens each time.