Hi everyone,
I am involved in the design of a building which has two PT concrete floors; 1st floor parking slab and second floor podium slab which supports the four storey wood structure.
The podium slab is 12.5 in thick and it supports dead load of 200 psf in excess of self weight and live load of 80 psf. The typical span i have is 30 ft. I am using ADAPT-PT for the design (EFM). I did not do the initial stress analysis while using ADAPT 7.2. But in new version of ADAPT PT 8 I was able to separate the self weight and super imposed dead load. I found that my initial stresses are very high for all the PT runs. When I say high means in the range of 6 squrt f`c, while allowable is 3 sqrt f`c. Precompression I have is in the range of 170 to 200 PSI. I would really appreciate if anybody can suggest me how critical these stresses are. Will concrete crack if I ignore these stresses.
And I can not do stage prestressing in this project.
Did anybody face the problem of cracks during jacking?
Should I ingore this? because my service stresses are fine.
Thank you,
I am involved in the design of a building which has two PT concrete floors; 1st floor parking slab and second floor podium slab which supports the four storey wood structure.
The podium slab is 12.5 in thick and it supports dead load of 200 psf in excess of self weight and live load of 80 psf. The typical span i have is 30 ft. I am using ADAPT-PT for the design (EFM). I did not do the initial stress analysis while using ADAPT 7.2. But in new version of ADAPT PT 8 I was able to separate the self weight and super imposed dead load. I found that my initial stresses are very high for all the PT runs. When I say high means in the range of 6 squrt f`c, while allowable is 3 sqrt f`c. Precompression I have is in the range of 170 to 200 PSI. I would really appreciate if anybody can suggest me how critical these stresses are. Will concrete crack if I ignore these stresses.
And I can not do stage prestressing in this project.
Did anybody face the problem of cracks during jacking?
Should I ingore this? because my service stresses are fine.
Thank you,