CSD72,
Hokie66 is right, the two beams in the 210’ direction has two spans, 120’ plus 90’ and in the middle there are two column, one for each beam. The two beams will be cast monolithically with the column support.
Preliminary FEM analysis indicates that the beams in the 210’ direction take...
Rapt,
Thanks a lot for your response. I raised the following questions for your thoughts:
1. You recommended the use of a real FEM analysis. If the analysis is elastic and does not take creep, shrinkage factors into consideration, then the results would have no difference from the other 3-D PT...
Thanks all for the response.
Rapt,
Actually there are two spans in the long direction, 120 feet and 90 feet, therefore the total structure is about 210 feet by 90 feet.
Currently only the beams in both directions are post tensioned and slabs are not. After the grillage analysis, we can see...
I have a long span two way slab situation and the basic info is like this: the slab is 120 feet by 90 feet and the slab is supported only by perimeter walls or columns. There are three PT beams in the short direction and two PT beams in long direction and therefore the spaning between beams or...
Rapt,
I've designed several different types of PT structures and I did pay some attention to the secondary reactions. I never see any significant seacondary reactions in comparsion with the reactions from graviy or lateral forces. I wondering when these secondary reactions could be significant...
Theoretically, you will need to apply secondary reactions to your lateral model. The secondary reactions, however, typically are very small and most times they are negligible. Sometimes we spot check the magnitude of the secondary reactions, but we never apply secondary reactions in the lateral...
Rapt,
The current version of ADAPT Floor Pro has the ability to calculate deflections considering concrete cracking. However, I believe that this calculation is strictly based on FEM results, instead of on ACI318 code.
Does RAPT 2D use EFM method as specified in ACI318? Does RAPT 2D calculate...
I used ADAPT extensively and designed several multistory PT buildings. ADAPT has two softwares: ADAPT PT and ADAPT Floor Pro. ADAPT PT is a 2-D program which will use equivalent frame method (EFM) for two-way slab design, which follows ACI318 codes. ADAPT Floor Pro is a 3-D program based on FEM...
I have an underground parking with basement walls on almost every side. The floor is 360 ft by 124 ft with one-way PT slab/beam system. The PT beam in the short direction has two equal spans of 62 ft. The one-way slab in the long direction has 12 equal spans of 30 ft. Columns are also present on...
