Earthquakes really are a great threat to critical water infrastructures in diff. areas of the world. A large amount of economic, environmental & produced by earthquakes on the particular regions or large cities like vast amount of damage, including ruptures, leakage & rusting etc. to many of underground water pipelines & distribution system & due to this there is loss of a large amount of water. Also due to earthquakes there is always a chance of rupturing & ignition of pipe & we may face blasts which is ruinous.
Steven Bartlett, a university of Utah Civil Engineer, has partnered with natural gas company Quester to use large expanded polystyrene blocks called “Geofoam” as a compressible, protective cover for a natural gas pipeline buried under the grows.
This low-impact technology will prove very useful if we have to change or replace already buried structure such as gas lines or other things without affecting adjacent buildings or other facilities.
In Europe, Asia to lighten loads & settlement under road Geofoam has been use for a long time. It will provide similar strength as soil but is of 1/100 th to the weight of soil. It also does not erode or deteriorate easily & save our construction time.
Bartlett researched the design & use it in Interstate 15 reconstruction project as a lightweight road embankment through the Salt Lake valley. Geofoam currently being used in the TRAX extension to the airport.
Quester which provides natural gas in the UTAH is using Geofoam in the lightweight cover for minimizing damage to gas pipeline as due to ground shaking several cracks developed in pipes.
Due to earthquakes in Wasatch fault zone in the Salt Lake valley, a fault breaks the valley just drop down as compared to the mountains. The pipe line will start to left up & pipes lie under 6-8 feet of complicated soil. This weight is normally too much for pipes to handle.
Bartlett & his student have shown this by performing it around the valley side of the Salt Lake City segment of the Wasatch fault, which withstand up to four times more vertical force than traditional soil cover.
Bartlett propped a “Slot Trench” design for that place in which a Geofoam block is placed in a narrow trench between a pipeline & the pavement above. It will displace the Geofoam block & compress it when the pipelines begin to lift up. As Geofoam is solid & having small air pockets that can compress without compromising the materials overall integrity. If we compress it further then it will slide upward along the trench slide walls & could eventually damage the pavement above but will not cause any damage to the pipeline.
Geofoam can reduce the earthquake pressure by 30-50 percent according to the Bartlett calculations. Also, it will reduce the requirement of steel to protect building from the earthquake damage. As compared with compacted soil, Geofoam is competitive when total construction costs are considered Bartlett says. It requires around one month for typical road embankment construction as compared to normal 12-15 monthly using traditional methods.
So, Geofoam is a good way to protect pipelines from earthquake damages.