On a DICE machine, if nothing happens when you click the icon to launch Google Chrome and it fails to open, that usually means you have left this browser running on another machine, for example in the AT labs, or within a Remote Desktop session.
From a terminal window run the command:
google-chrome
This should provide useful details on what the problem is, including the hostname of the machine you left it running on.
The profile appears to be in use by another Google Chrome process (57463) on another computer (gecko.inf.ed.ac.uk). Chrome has locked the profile so that it doesn't get corrupted. If you are sure no other processes are using this profile, you can unlock the profile and relaunch Chrome.
If possible you should cleanly end that session before starting a new one. If that's not possible, you will need to unlock the profile by deleting the lockfiles
From a terminal window enter your profile configuration:
cd ~/.config/google-chrome
Delete all lockfiles
rm -Rf Singleton *
You should then be able to launch chrome as usual.