BlastResistant
Structural
- Jun 4, 2007
- 47
Reference 5.9.5.4.3a AASHTO LRFD 4th Ed, 2007.
When determining "prestress loss due to shrinkage of girder concrete between time of deck placement and final time", it is necessary to first calculate the value of K_df. When calculating K_df, what values do you folks out there use for "t_f" the "final time" after deck placement? The commentary for C5.9.5.4.2c gives typical values for t_i (0.75 days), t (120 days between strand tensioning and deck placement). However, I don't see any recommended values to use for "t_f" anywhere in the Code.
Thanks in advance.
When determining "prestress loss due to shrinkage of girder concrete between time of deck placement and final time", it is necessary to first calculate the value of K_df. When calculating K_df, what values do you folks out there use for "t_f" the "final time" after deck placement? The commentary for C5.9.5.4.2c gives typical values for t_i (0.75 days), t (120 days between strand tensioning and deck placement). However, I don't see any recommended values to use for "t_f" anywhere in the Code.
Thanks in advance.