Spliced Concrete Post Tensioned Beam Cost 3

[decade]

I am working on a project which the client has asked for a cost comparison between the steel alternate I have proposed and a concrete post tensioned beam alternate. The spans are 150'-80'-120'. From experience I believe a 150' span will have to be a spliced concrete beam but I'm having difficulty finding any ACTUAL bid data concerning post tensioned concrete beams.

I've been searching DOT websites and have yet to find a bid tab with a post tensioned concrete beam. Does anyone know of a source for CURRENT cost information?

 

[crossframe]

Try the Washington State DOT website. I don't know about bids tabs, but I recall they do (or at least used to do) a fair amount of precast girder segments that are post-tensioned together. Alternatively, some of the precast prestressed shapes (bulb tees and the like) may approach 150 ft.

 

[Qshake]

Our company has recently designed a 200'+ single span spliced concrete I-girder bridge for Florida DOT. These girders were over 12' deep and aren't something you see everyday. FlaDOT was adament about having a clear span underneath so we continued with the design - loads of fun!!

I don't think you need to take a 150' to that extreme. We're also using a modified bulb tee for a 140'+ span in another southern state. You can always use HP concrete and if necessary, widen the web for shear. Also if necessary move the girder spacing in to minimize loading. You may not always have that last option available.

Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[ghghghgh]

Keep in mind the eccentricity of a 150' vs. 80' concrete span my add some to the substructure cost (unless your steel option was simple spans).

 

[oldmanK]

I was involved as a grad student on a Tennessee DOT project that consists of 2 spans of 159' each. 72" bulb-tee prestressed girders (156') were made continuous via deck reinforcement and standard details in the diaphragm over the pier, with the composite deck and diaphragm cast in the same pour. (f'c=10 ksi)

 

[AndyZ]

http://www.virginiadot.org/business/const/resources-bidtabs.asp

for bid tabs on drop-in post tensioned beams Look at August 2003 on the VDOT website above
Winning Contractor was Archer Western (they won 2 that month)
Contract ID C00014691B02

I believe the appropriate items are listed below.

NS PRE CONC BEAM BULB-T PRE CONC BEAM
BULB-T DROP-IN SEGMENT

NS PRE CONC BEAM BULB-T PRE CONC BEAM
BULB-T END SEGMENT 405

NS PRE CONC BEAM BULB-T PRE CONC BEAM
BULB-T HAUNCH SEGMENT 405

NS PRE CONC BEAM BULB-T PRE CONC BEAM
BULB-T 1956MM (44M - 48M) 405

NS BRIDGE SUPERSTRUCTURE BRIDGE
SUPERSTRUCTURE MMFX-2 REINFORCING
STEEL ATTD

NS BRIDGE SUPERSTRUCTURE BRIDGE
SUPERSTRUCTURE POST TENSIONING SYSTEM
ATTD