I started new Beans child theme, and I never had an issue like that earlier - when I use uk-icon- class, less compiler creates wrong awesomefonts url: http://wp-content/themes/tm-beans/lib/api/uikit/src/fonts/fontawesome-webfont.woff2 etc. It looks like less compiler issue, but I thought it was fixed long time ago (2012..?). Any clue what could cause that or how to check that? Does it have anything to do with latest Wordpress actualisation?
Could you kindly provide us with a link to your site and the code snippet you are adding to your child theme so that we can try reproducing the issue?