Jeddah Tower was calculated in five different Structural Software Programs to be sure about results.
The tallest building in the world is one thousand meters high and was specified in reinforced concrete with an 85 MPa strength.
Which Structural Analysis Software does make you feel safer? How do you calibrate the structural behavior of your buildings
Among these 5, i am using first 3 to great extend. Now a days any software in the market provide similar analytical power and options.
What make it different is is how user friendly in inputs and result depiction. What ever you makes with FEM, i can get good night sleep ,only should i do my hand calculation and use of my own spread sheets to validate the FEM results.
it is matter of correct analysis of loads, assessing reasonable relative stiffness’s and boundary conditions, assessing long term creep and shrinkage then incorporate them in construction stage appropriately.
We do work with a result spectrum where based on the assumption and inputs we may end up with upper bound or lower bound ends of the possible results spectrum. Reasonable correctly assessed manual calculation will provide you a good indicative of where you stand between in your possible result spectrum. That makes me a good night sleep
If the same elements, boundary conditions, loads, and basic solvers are used, each will give the same results. Many analysts will mistake the different source code for default meshing approaches as one software being more accurate than another – it’s important to understand and account for the limitations between each package.
At the end of the day, your structural model is just a matrix, and all programs assemble the matrix using the same foundational approaches.
Of course, as one moves left to right from ETABS to ABAQUS, one would expect there to be an ability to refine the model (i.e. use higher-order elements, nonlinearities, more advanced boundary conditions, sparse solvers etc.) and perhaps achieve a more “accurate” set of results.
A more refined check on the results would be to have the analysis completed by five different engineers! That would identify how the analysis results would change under the differences in modelling assumptions and approaches, to which such models tend to be the most sensitive.
Direct displacement base design and nonlinear time history analysis are the best guaranties to perform safe mega tall building under extreme loads. Staged non linear construction to perform the effect of creep and shrinkage and differential displacement for vertical structural stability “” Vertical shortening effects due to the time depend creep and shrinkage of concrete”” , vibration comfort under steady state wind action , soil structure interaction . story spectrum and vertical differential effect of time time depend creep and shrinkage are necessary to design curtain wall and cladding heavy façade . All soft as Midas gen ..sap2000 etabs. Softish possess all options to design this type of buildings with great accuracy.
MIDAS was used for the “staged construction” option, that not that many software’s had at the time. Abacus is great for dynamic analysis, so important in tall buildings. Strand7, ETABS, etc were used not just to compare results, but also for different purposes as above described. Indeed, it was a great presentation.
Strand7 is a very good software, with algorithms advanced and very stable.
The reason why it has been used instead of other ones is easily understandable looking the pic: has high performances, comparable to Abaqus.