Calculation
Anet = t · (b − n · d0); σnet = F/Anet
Every hole removes load-carrying cross-section; net-section stress is always higher than the stress based on the unweakened gross section.
σnet = F/Anet, Anet = t·(b − n·d0)
Riveted plate net-section stress
Every hole removes load-carrying cross-section; net-section stress is always higher than the stress based on the unweakened gross section.
MINTSI
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Result
Select a target and calculate.
Understand the inputs
- Net-section stress σnet — Tensile stress in the plate's weakened net cross-section.
- Tensile force F — Tensile force transmitted through the plate.
- Plate width b — Total plate width transverse to the load direction at the section considered.
- Plate thickness t — Plate thickness at the section considered.
- Hole diameter d0 — Diameter of the rivet holes in the critical section.
- Holes in the section n — Number of rivet holes crossing the section considered.
- Net cross-section area Anet — Load-bearing cross-section area reduced by the hole area removed.
Example
20,000 N on an 80 mm wide, 10 mm thick plate with one 12 mm hole give Anet = 10 mm · (80 mm − 12 mm) = 680 mm² and σnet = 20,000 N / 680 mm² ≈ 29.4 MPa.
Assumptions and limits
Straight, non-staggered hole row transverse to the load direction; staggered (zigzag) hole rows require checking a different, potentially shorter critical section separately. Local stress concentration at the hole edge is not included in the nominal net-section stress.
Understand Riveted plate net-section stress
This calculator finds the tensile stress in the net section of a riveted plate — the cross-section weakened by rivet holes — from force, plate width, thickness and hole geometry.
What does this quantity describe?
Every rivet hole removes load-carrying material from the plate cross-section. Net section at the critical line follows from Anet = t·(b − n·d0), where n is the number of holes crossing that line. Net-section stress σnet = F/Anet is always higher than the stress based on the full gross section, F/(b·t).
This is like a perforated sheet of paper: the actual tear-resistant width is not the full sheet width but the width minus all holes along the worst tear line — the more or larger the holes in a row, the weaker that line is compared with unperforated material.
Formula and variables
Anet = t · (b − n · d0); σnet = F/Anet
Anet = t·(b − n·d0)σnet = F/Anetb = Anet/t + n·d0
| Symbol / input | Meaning |
|---|---|
| Net-section stress σnet | Tensile stress in the plate's weakened net cross-section. |
| Tensile force F | Tensile force transmitted through the plate. |
| Plate width b | Total plate width transverse to the load direction at the section considered. |
| Plate thickness t | Plate thickness at the section considered. |
| Hole diameter d0 | Diameter of the rivet holes in the critical section. |
| Holes in the section n | Number of rivet holes crossing the section considered. |
| Net cross-section area Anet | Load-bearing cross-section area reduced by the hole area removed. |
Choose the inputs correctly
Plate width b, thickness t, hole diameter d0 and hole count n across the critical section set net section; together with tensile force F this gives net-section stress.
How to use the calculator
Enter plate width, thickness, hole diameter and hole count to compute net section, and add tensile force for net-section stress. For staggered hole rows, additionally check whether a diagonal section is more critical.
Worked example
20,000 N on an 80 mm wide, 10 mm thick plate with one 12 mm hole give Anet = 10 mm · (80 mm − 12 mm) = 680 mm² and σnet = 20,000 N / 680 mm² ≈ 29.4 MPa — versus only 25 MPa based on the full gross section.
Understand the result and units
The net-section stress of 29.4 MPa is about 18% above the gross-section stress of 25 MPa. This gap grows with the ratio of hole diameter to plate width and must be accounted for in material selection and safety considerations.
Width, thickness and hole diameter are given in mm, area in mm², and the resulting stress in MPa (N/mm²).
Gross section versus net section
The gross section A=b·t describes the full, unweakened plate area and gives the lowest, most optimistic stress estimate. Net section Anet=A−n·d0·t instead accounts for the area actually missing at the critical line because of rivet holes, giving the higher stress that governs the tensile strength check. A complete strength verification of a riveted tension strap must always compare net-section stress against the plate material's tensile strength, not the more optimistic gross-section stress.
Typical applications
The calculation is used to check riveted tension straps, gusset plates and connection plates, ensuring the plate itself does not fail from the weakening at rivet holes before the rivets reach their limit.
Assumptions, limits and common mistakes
The model applies to a straight, non-staggered hole row transverse to the load direction. For staggered hole rows, a diagonal section through multiple holes can actually be shorter and therefore more critical than the straight line; this must be checked separately using the zigzag rule. Local stress concentration right at the hole edge is also not included in the nominal net-section stress.
Common mistake: A common mistake is checking only the straight section for staggered hole rows, even though a diagonal line through multiple holes can be shorter and therefore more critical at tighter hole spacing. Net-section stress is also sometimes confused with gross-section stress, even though the two use different reference areas.
Frequently asked questions
Why is net-section stress always higher than gross-section stress?
Because net-section stress is referenced to the load-carrying area reduced by rivet holes, while gross-section stress uses the full, unweakened area.
What do I do with staggered hole rows?
Additionally check a diagonal section through multiple holes using the zigzag rule; it can be shorter and therefore more critical than the straight line at tight hole spacing.
Which section is the critical one?
Whichever has the smallest net cross-sectional area; for a straight hole row this is usually obvious, for staggered rows it must be specifically searched for.
Does this model capture stress concentration at the hole edge?
No, it gives only the nominal stress averaged over the net section; actual stress at the hole edge is locally higher.
How does this check relate to the shear and bearing checks?
All three are independent, equally important checks for a complete riveted joint verification; which one governs depends on the specific geometry.