But I don't think you are ever going to know exactly how that connection was set up. Unless you've got some hard evidence then it's pointless speculation.Please don't delete this again Mick as it is very on topic.
These break elements are crucial and I think it would inform us to know what type of element NIST used (COMBIN37) and how that may have changed the analysis. I would also then like to put Dr Hulsey's model under the same scrutiny to compare them. I am going through the notes at the moment for any of Dr Hulsey's model details that might be there.
But I think it would do no harm to establish just how many directions a unidirectional element can move in.
As I said earlier, I think it's one, but I am prepared to be wrong.
I've gone through the notes, they had build some simple models and bent them and heated them a bit. They were trying to figure out how to model the connections. The last connection related entry is:
Then two weeks later they had another hard drive crash, and nothing was heard from them since.External Quote:
Date: 08/21/2015 Working Hours: 8
Submitted by Zhili Quan
Today, "1 joint link" elements were studied. However, despite tons of effort being put into modeling the elements to simulate the stiffness between multiple elements that have one of their joints that share the same location, it cannot be done. Later, after a phone call consultation session with the company that provides SAP2000, it was found out that "1 joint link" elements can only be used to connect elements to the ground. Therefore, it cannot be used to simulate the stiffness between different elements that are connected.
"2 joint link" elements were also studied. After numerous test-modeling, it was found that a "2 joint link" element can be put into one shared location of two different joints of two different elements therefore giving the stiffness between these two elements.
Figure 1 shows a triangular "shell" element with one of its joints that shares the same location as one of the joints of a "frame" element. A "2 joint link" element has been inserted between these two elements.
However, when there are multiple elements that each has one of their joints sharing the same location as what is shown in Figure 2. The highlighted location has 6 different joints all clustered together. It takes very complicated connecting condition to model the partially composite elements. More study has to be conducted to resolve this issue.