cessna98j
Civil/Environmental
- Jun 12, 2003
- 76
Hi All - hypothetical question:
Let's say we have a pipeline that carries a pressurized petroleum gas product for a distance near the shoreline, and the area is subject to liquefaction and lateral spreading.
Let's also say the pipeline is only full of product 5% to 10% of the time, empty the rest of the time.
If said pipeline were supported by pipe racks, the racks would be governed by ASCE 7, ch 15 (non-building structures). To satisfy structural requirements, the rack foundations would have to be supported by piles and there would have to be extensive (and expensive) ground improvements to prevent failure of the pipe rack foundations (which only support the pipe) due to lateral spreading.
Now what if we put the pipe on at-grade sleepers? The sleepers and anchorage would be designed for the seismic accelerations - but could we forego the ground improvements for lateral spreading if it can be rationalized that failure of the pipe itself will not create a public risk, because the pipeline would have seismic isolation valves and released product would be below risk thresholds?
I'm trying to find out if the pipe is on sleepers, are we no longer subject to the building code requirements of designing to mitigate lateral spreading? At what point can we call it a pipe and not a structure??
Any thoughts or discussion greatly appreciated!
Let's say we have a pipeline that carries a pressurized petroleum gas product for a distance near the shoreline, and the area is subject to liquefaction and lateral spreading.
Let's also say the pipeline is only full of product 5% to 10% of the time, empty the rest of the time.
If said pipeline were supported by pipe racks, the racks would be governed by ASCE 7, ch 15 (non-building structures). To satisfy structural requirements, the rack foundations would have to be supported by piles and there would have to be extensive (and expensive) ground improvements to prevent failure of the pipe rack foundations (which only support the pipe) due to lateral spreading.
Now what if we put the pipe on at-grade sleepers? The sleepers and anchorage would be designed for the seismic accelerations - but could we forego the ground improvements for lateral spreading if it can be rationalized that failure of the pipe itself will not create a public risk, because the pipeline would have seismic isolation valves and released product would be below risk thresholds?
I'm trying to find out if the pipe is on sleepers, are we no longer subject to the building code requirements of designing to mitigate lateral spreading? At what point can we call it a pipe and not a structure??
Any thoughts or discussion greatly appreciated!
