PittEng88
Structural
- Feb 14, 2015
- 90
Hello All,
I have a contractor who has requested a change to the approved pouring sequence specified in the bridge plans in an effort to save time.
The bridge is a three span continuous spread box beam superstructure with a PennDOT Skew of 83° (7° AASHTO Skew). All three spans are 100 feet long. The bridge deck uses 4 ksi concrete. The plans call for the deck concrete in the positive moment regions to be poured first, followed by the negative moment regions over the piers. Construction joints will be used to separate the regions. All pretty standard stuff.
The request is for the initial pour of the deck. Due to some delays on the jobsite, the contractor only has the beams set for the first span. In an effort to save time while they are excavating for the remaining substructure units, the contractor has asked if he can go ahead and pour the positive moment region portion of the deck in the first span. He is proposing on moving the construction joint back 7’ from its original position into the positive region. The 7’ will allow for him to place the negative moment deck steel and have the proper splices when the second span is finally erected.
I understand that the deck pour sequence is in place to help avoid cracking over the negative moment regions. So, I am just wondering if moving the joint back 7’ on a 100’ span would be that big of a deal.
Has anyone has ever dealt with this before and if so would they take issue with it?
I have a contractor who has requested a change to the approved pouring sequence specified in the bridge plans in an effort to save time.
The bridge is a three span continuous spread box beam superstructure with a PennDOT Skew of 83° (7° AASHTO Skew). All three spans are 100 feet long. The bridge deck uses 4 ksi concrete. The plans call for the deck concrete in the positive moment regions to be poured first, followed by the negative moment regions over the piers. Construction joints will be used to separate the regions. All pretty standard stuff.
The request is for the initial pour of the deck. Due to some delays on the jobsite, the contractor only has the beams set for the first span. In an effort to save time while they are excavating for the remaining substructure units, the contractor has asked if he can go ahead and pour the positive moment region portion of the deck in the first span. He is proposing on moving the construction joint back 7’ from its original position into the positive region. The 7’ will allow for him to place the negative moment deck steel and have the proper splices when the second span is finally erected.
I understand that the deck pour sequence is in place to help avoid cracking over the negative moment regions. So, I am just wondering if moving the joint back 7’ on a 100’ span would be that big of a deal.
Has anyone has ever dealt with this before and if so would they take issue with it?