Last Updated on January 5, 2026 by Maged kamel
Tension members-part -2.
In this post, Tension Members, part 2, we will discuss gross, net, and net effective areas. What is the difference between pitch and gauge? How do we estimate the hole diameters for the design of tension members?
How do we estimate the net area of tension members?
The following topic concerns gauge distances if we have a single angle with four bolted connections arranged in two gauge lines.
Assume the applied force acts at the angle’s centroid. The first and second lines of fasteners are arranged in the same direction as the applied force.
The first and second gauge lines have two fasteners. The vertical distance between them is the gage distance, represented by the symbol g. It runs perpendicular to the force’s direction.
The inclined distance joining between the two fasteners, denoted as D1, has a horizontal distance in pitch distance S1, while the vertical distance component is gage g.
The edge distance, known as ED1, is measured from the center of a hole to the nearest edge. This value is the horizontal distance.
We can get the net width, which depends on the bolt route. If our section is vertical, we will deduct the hole diameters from the vertical width, based on the number of bolts.
To get the net width while working with a zigzag line distance between the bolts, add S2/4 g, where S is the longitudinal distance as a center-to-center spacing, and the gauge g, which is the transverse distance, and deduct the hole diameters for bolts that the section is cutting.
Provision B4.3 in the specification.
The following slide image shows the new provision for tension members in the design requirements under B4 in AISC-360-22, page 15, for member properties. The provision B4.3 includes the determination of gross and net areas. Sub-item 3b includes instructions for estimating the net area.
Adding 1/16 inch to account for damage from punching is included in the previous specification on page AISC-360-16 on page 20.“In computing net area for tension and shear, the width of a bolt hole shall be taken as 1/16 in. (2 mm) greater than the nominal dimension of the hole.”
Discussion of net area Term.
Adding 1/16 inch to account for damage from punching is included in the new specification on page AISC-360-22 on page 24.“In computing net area for tension and shear, the width of a bolt hole shall be taken as 1/16 in. (2 mm) greater than the nominal dimension of the hole.”
In practice, it is advisable to add 1/8 inch to account for damage from punching holes. Please refer to the following slide image for more information. Please refer to the Steel design book by William T. SEGUI, 6th edition, page 44, Chapter 3.
The PDF data for this post can be downloaded and removed. Please refer to the following PDF document.
The following post is titled: An easy approach to Table 2-4 for various steel elements.
For a helpful external Chapter 3 – Tension Members– Bartlett Quimby