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The Contractor on a steel pile trestle bent bridge has proposed placing a welded pile splice within the concrete pile cap. The pile (PP36x1.0) is embedded 36" into the cap and they wish to splice it 4" into the cap (prefabbed top 32" piece) Would you have a concern in splicing that close to...

I have never designed a timber pile...but find the need to do it now. I have done enough timber design to get the concepts, but am stumped about the round member... How do you determine the shear capacity of a round member? Can you use the typical 85 psi allowable shear stress of a timber...

Thanks, But I was looking for Hot Working.....i.e. heating up the steel and forcing it to shape.

I am currently designing a fix for a damaged historic steel truss bridge. A couple of the members recieved only minor local bending (on flanges, etc..) as a result of the hit. I plan on having the contractor hot work the area back to shape. Does anyone have sample specifications for this type...

You will have to use a coffer dam. very typical in bridge engineering

I understand the concept, in either case, "c" - depth to neutral axis and "a" depth of Whitney stress block would be proportionally the same....and the "a" for the T-Beam would be less than that of the rectangular section

I agree....but even if I use a more "reasonable" cog...i.e. center of span... yc=4.95" for a dp=76" I still get a rectangular section "c" of 9" and a T-Beam "c" of 8.7"...... I have went on and it really does not make a difference in the end, just does not feel right

Although this "problem" occurs throughout the entire beam, the one that I am primaraly trying to solve falls at the development point of the strand (approx 8' from the end of the beam) The precast supplier drapes (aka harps) the strand to minimize the prestressed enduced moment near the ends of...

Error in above post.... line 3 should read.... the "web" is the flange of the Bulb-T = 48", while the "flange" is the effective width governed by beam spacing

Thanks for the reply...here is the missing info: Slab thickness = 8in the "web" is the flange of the Bulb-T = 48", while the "web" is the effective width governed by beam spacing dp = (beam depth + deck + haunch)-(ycg) therefore.. db = (72" + 8" + 0.5") - (22.1") = 58.4" (falls in...

I am currently doing a strength design hand check for a 72" Bulb-T. While doing the check for rectangular-vs-T Beam action, I am getting "odd" results for the depth of the neutral axis "c-value" (using equations in LRFD 5.7.3.1. Using my numbers I get that the rectangular section "c" is more...

Your local prestress supllier usually has design aids for this sort of question. This is basically an estimate that you can go further into design with. As with going through the design process, think of the problem from the beam side. i.e. @ transfer, just the beam @ deck pour, beam supports...

The Ohio detail is very similiar to the Oregon DOT method

I guess my question was poorly worded. I understand that it is possible...given the money and extra cost. Do you have a history of performance of such installations? How did you handle the case of the possible impact and ensuring that the pole fails before the deck?

Has any of you ever placed a cantiler mast arm signal pole within the span of a bridge? The signal designer on a project that I am working on is pushing for this. I feel that inducing approximately 240kip-ft into the deck and Bulb-T beams is unreasonable. This is complicated by the fact that...

I was asked today about why a precast prestressed girder's camber goes up between initial release and 3 months and 5 years..... I have always just accepted that it does. I am sure that I was proven it in college, but the reason has left me. Can anyone please help with the reasoning? thanks

I often have a difficult time knowing what steel to spec for the minor uses...i.e a stainless steel rod, should it be A304, A307? Does anyone know of a website or document that helps aid in this selection process?

The local standard for connecting adjacent prestressed precast slabs is via tie rods. Recently, a local Contractor has submitted a set detour structure plans that use a "weldment" detail to connect the slabs. Have anyone on this forum used this detail? if so, how well does it perform? I have...

I totally agree with "graybeach"....seismic considerations should govern the design

I am currently designing a widening/rehab on a historic concrete bridge. I need to place two utility sleeves through the end bent. I plan on having the contractor core through the concrete (12" dia and 14" dia sleeves). the holes are located approx 5 1/2 feet below the deck surface. I am...