1. The stress principle is different
The mechanical anchor bolt is allowed to have smooth screw, which is stressed by mechanical key force;
The expansion bolt mainly through the extrusion effect, produces the friction, realizes the stress.
2. The anchoring depth is different
The anchoring depth of mechanical anchor bolt should be less than 10d;
The depth of expansion bolt is mainly determined by concrete strength and expansion bolt specification.
Because the expansion bolt in the use process, will produce the stress concentration phenomenon to the concrete, thus causes the destruction probability to increase greatly, the structure is not safe, therefore, the expansion bolt cannot be used in the cracked concrete. Therefore, it has been basically prohibited in the design of curtain wall and so on. If the drawing is to be reviewed, the expansion bolt will definitely fail.