#MATL, 15 bytes '_|__'700:)70e! Of course, you can [Try it online!](http://matl.tryitonline.net/#code=J198X18nNzAwOik3MGUh&input=) Explanation: '_|__' % Put a brick on the stack 700 % 700 times :) % Makes a happy mason... 70e! % Secret freemason code OK, actually, it works as follows: '_|__' % Put the first bit of the string on the stack 700: % Put 1, 2, ..., 700 on the stack as array ) % Index into the string, modularly. Result: '_|___|__ ... __' 70e % Reshape into 70 rows (and consequently, 10 columns) ! % Transpose to get the desired output.