Technical Articles and Engineering Guidance

Engineering guidance for the contemporary engineer. Technical articles that can be leveraged by the practicing engineer at work to facilitate or enhance design and analysis endeavors.

Posts tagged 'failure'

Did you check for Pull-through?

Not surprisingly over my career…I’ve seen it once and I continue to see it again and again and again…a failure to check a fastened joint for pull-through. What is seemingly a simple stress check is often overlooked. This tip provides a quick method to check for pull-through failure anytime...but hopefully you check during the preliminary phase of the design before a failure or a messy redesign is required. A check that readily ascertains whether a composite joint is thick enough, or possesses the minimum inter-laminar shear strength needed to prevent a pull-through failure is discussed in this article.


quick tipPerforming a simple preliminary check for fastener pull-through is good practice. The equation below can be used to calculate the pull-through stress for either countersunk or protruding head fasteners.

Pull Through Equation

pull-through  protruding  fastener  failure

2018-05-07 07:29:39
 

Flatwise Tension in a Curved Plate

Composites…It’s not just a 2D world…got Flatwise Tension? 

Too often I hear both analysts and designers toss around the term quasi-isotropy…a mythical monster to some, an in-plane idealization to simplify a 3D problem for others. I for one am guilty…because I appreciate the fact that you can take a complex 3D composite problem and knock it down a dimension...in this case, the out-of-plane direction.

tension  stress  radius  plate  flatwise  failure  curved

2017-09-17 04:42:20