CMU interlocking blocks come in a variety of shapes and sizes but what they all have in common is that they don’t need mortar to hold them together. Interlocking blocks connect to each other through flanges, pins or a lip and notch configuration. There are several different lip and notch configurations. The easiest way to understand how they work is to think of legos. One block will have an indention or notch and the other block has a protrusion that matches the notch. A strong bond is formed once these two blocks are fitted together. Just think of how hard it is to separate two lego pieces.
Interlocking blocks can withstand heavy pressure loads. They can be used in building retaining walls, flood protection walls, and more. An interlocking block gets its strength from the other interlocking blocks that build the wall.