Load History Deflections

RE: Load History Deflections

Seth Guthrie — Fri, 08 Nov 2019 19:35:03 GMT

I checked with the development lead and he explained a few things that might be making the difference,

"There is a little bit of magic around that 3 day value that is causing the behavior they are seeing. We somewhat arbitrarily chose that anything less than 3 days would be considered “instantaneous” for the purposes of our calculations. This was primarily for the savings of the computational expense. For loadings of duration 3 days and longer we do both an instantaneous portion iteration and then a sustained portion iteration – and the sustained portions generally take more iterations to converge. For less than 3 days we only do the instantaneous portion and skip the sustained portion altogether. While this can obviously cause some difference in the calculated deflection, the expectation was that the change would be small.

There is no way to predict deflections with any reasonable degree of accuracy with the creep/shrinkage that might occur over a couple of days, which is why this granularity of time was thought to be insignificant."

RE: Load History Deflections

Seth Guthrie — Fri, 08 Nov 2019 16:54:33 GMT

That is a little curious. I added extra steps tp have results at day 1, 2 and 3 and then things are essentially constant. I'll see if I can tell anything more from the original logs.

RE: Load History Deflections

Stuart Riesner — Fri, 08 Nov 2019 15:06:30 GMT

communities.bentley.com/.../Ram-Concept-Deflection-Tests.cpt

RE: Load History Deflections

Seth Guthrie — Thu, 07 Nov 2019 21:53:03 GMT

I don't see any files in there. Try zipping it first.

RE: Load History Deflections

Stuart Riesner — Thu, 07 Nov 2019 21:44:58 GMT

We uploaded the file with the original post. We played around with different combinations of duration and initial load application and we seem to get similar answers.

RE: Load History Deflections

Seth Guthrie — Thu, 07 Nov 2019 21:21:27 GMT

Try pushing out your initial load application a few more days. Do you still see the big change in the early days after load application? If that's not the issue, send the file.