Dennis59
Structural
- Dec 29, 2000
- 56
Hello and forgive me for what you may consider a silly post...
My work requires that sometimes I need to evaluate existing structures. I have done that with many different material types.
With open web joists, there is almost always a metal tag somewhere on the joist that tells the manufacturer and some other information. With that tag, I can get in touch with the original design information. And if there is no tag, at least I can physically measure everything and calculate an approximate capacity.
With precast it's a different story. Building owners usually don't have construction records (like shop drawings, etc), especially on older structures. Just looking at a precast hollow core slab or a tee, it is impossible to know the manufacturer, much less where the prestressing strands or other reinforcement might be. Analyzing the member for new loads is made much more difficult. If I can't get at the ends of the member to see the strands, then we need to hire a testing agency to locate strands, and then chip out concrete until we find the strand in order to measure size and depth.
My question: why doesn't the precast industry have a system like the open web joist industry? A small metal tag could be cast into the member with manufacturer name and date of production and/or similar information. Then in the future if changes are needed on that member at least there would be a place to start with determining the member capacity.
Any thoughts?
Thanks for reading.
My work requires that sometimes I need to evaluate existing structures. I have done that with many different material types.
With open web joists, there is almost always a metal tag somewhere on the joist that tells the manufacturer and some other information. With that tag, I can get in touch with the original design information. And if there is no tag, at least I can physically measure everything and calculate an approximate capacity.
With precast it's a different story. Building owners usually don't have construction records (like shop drawings, etc), especially on older structures. Just looking at a precast hollow core slab or a tee, it is impossible to know the manufacturer, much less where the prestressing strands or other reinforcement might be. Analyzing the member for new loads is made much more difficult. If I can't get at the ends of the member to see the strands, then we need to hire a testing agency to locate strands, and then chip out concrete until we find the strand in order to measure size and depth.
My question: why doesn't the precast industry have a system like the open web joist industry? A small metal tag could be cast into the member with manufacturer name and date of production and/or similar information. Then in the future if changes are needed on that member at least there would be a place to start with determining the member capacity.
Any thoughts?
Thanks for reading.
