Bolts are simple machines that play one of the most important roles in the complex world of structural steel. They help create the heights of our cities and lengths of our bridges.
Structural Bolts are a special breed of bolt. They are designed specifically to create maximum clamping force and to fail properly when something goes wrong. To do this properly they have three important features that set them apart from standard bolts.
Structural bolts are designed to break or snap into two pieces.
- There is no way to see what is happening inside a fastener assembly. If something goes wrong and damage starts to occur a bolt will break as a failsafe to prevent the adversely affected bolt from remaining in service within a structure.
Structural bolts have a thicker and wider head.
- The extra head size more effectively distributes the load created by a tightened bolt. It also matches the nut, allowing the installer to turn either end with the same tool.
Structural bolts have a shorter thread length.
- The shorter thread length is the result of efforts to increase the length of the bolt’s shank. Adding threads to a bolt affects its integrity negatively so the longer a bolt’s shank the more resistant it is to failure from torque or tension. The shank also resists shearing better than the threaded portion of the bolt.
Our goal should be to understand the role a bolt plays in building a structure and position the bolt to succeed in that role. You can learn a lot more about structural bolts and their role in our Free Content Library.