Sajid Usmani

Not beams exactly but Band-Beams can post tensioned easily and economically. It is common especially for large spans. Pl see the book Bangali S Taranath. It is not necessary every time PT slab is economical or feasable. Soon you will see it is hapenning in Karachi. It has been designed but unfortunately not executed yet. Hope this time it happen.

I appreciate that atleast you people have been thinking a very posetive and constructive plan.

Wind Tunnel Loading Data


Wind Tunnel Loading Data

Wind tunnel data is huge and tedious to input in ETABS or structural softwares. This data is produced from the wind engineering team’s softwares and usually provided in excel format. Usually if the building not regular, number of load cases are more than 20.
How to import all that data into ETABS model is still a big issue because ETABS only lets you export the data to excel. There is no import facility from any database or excel sheet. Unlike SAFE and SAP, ETABS does not offer the facility to use interactive database editing.
Well, I encountered this problem in my recent project, and then atlast I was able to import this bulk of numbers successfully in ETABS by using excel and VBA. Although I wrote the code for the format of data presented to me by the wind engineering team but it can be quite easily modified to satisfy other formats. Alternatively the wind tunnel data can be reformatted to match with the format, the coding accepts.
If someone out of you has faced a similar problem and is unable to execute it, you can contact me personally. May be I upload the sheet soon here but for sure not now.

well i dont believe SAFE gives wrong results as compared with manual calculations.. and here im talking about SAFE 12

But you have to consider following things:-

1) check the load size for perimeter calculation
2) apply the correct parameter for location of column...For example if it is interior column , select the point goto Design>Punhcing Overwrites and make it interior

3) Make correct cover settings. Goto Design> Design Preferences and put the correct cover and bar size
4) Make sure you are familiar with the load combos for which you will design your structure or punching

After analysis, right click on the point of column you will see detailed calculations for punching and the governing combination. Make sure SAFE 12 is calculating the effective depth and the perimeter correct which will surely be correct if you follow above steps. You can also check punching calculations of other non governing combinations.

This is not a manual calculation. How do I know if your forumlas are right in excel. The only way to check this calculation is to make a new calculation.

reminds me of a question on mid term of masters exam, where a concrete wall had temperature of a -30 on 1 side and +18 on other with an udl on top and reinforcement placed at the center of the wall and the question to find the critical load for that given reinforcement and wall section.. that was pretty cruel !