WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
(OP)
Hi all,
we are designing a natural gas pipeline, of 24'' diameter. My question is, when an achor block is required. The pipeline that we are designing is an underground carbon steel pipe, which in some cases has over 40% slope! Is there any rule of thumb or good engineering practice for anchoring the pipeline if its slope is over one specific percentage?
we are designing a natural gas pipeline, of 24'' diameter. My question is, when an achor block is required. The pipeline that we are designing is an underground carbon steel pipe, which in some cases has over 40% slope! Is there any rule of thumb or good engineering practice for anchoring the pipeline if its slope is over one specific percentage?





RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
To be honest, the fact you asking these basic type of questions and seem to come from a civil background makes me worried that you don't have the right experience to design such a large diameter gas line. If this pipeline fails in service you can have a very large fire. Please think about using experienced pipeline engineers.
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
thanks for your answer, of course I am not the one who designs the pipe, don't worry, the world will still be a safe place after this one! I am just asking to have a feeling about the project. Do you have any recommendations for 77- 83% slopes? Do you still think that the friction of soil would be able to hold the pipeline? What about using a thrust block?
Thank you in advance
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Anchors, or weights to prevent buoyancy, probably not.
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Tsofa , you're describing a near vertical slope. Where are you routing? Up the andes? Past the normal angle of repose for soil, around 30 degrees, you won't get whatever you dig or blast out to stay put so for most slopes beyond this you need to find another way.
As cvg says you'll have more issues than anchor blocks... Providing that the length of pipeline at that sort of slope is less than 150 to 200 m, you should be ok to build from the bottom up. You may need to make sure that the base is well compacted if you have a formed bend at the base of what sounds like a cliff or escarpment, but the general rule in pipelines is to avoid anchor blocks and hard edges wherever possible as high shear loads and stress concentration around anchors is what breaks pipelines. It would be great to see a vertical profile of these very high slope areas and then you may get more feedback.
Design it then run it through a stress analysis
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
40% slope is 40 y in 100 x
21.8 degrees (from horizontal, for all you civils out there)
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
You still don't need anchor blocks though.
Tsofa, just confirm you're working in percent and not degrees and post a profile!
My motto: Learn something new every day
Also: There's usually a good reason why everyone does it that way
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Angles steeper than the angle of repose of the soil of course are NOT a good idea.
Angles steeper than what would give a reasonable trench breaker center/center distance would also not be reasonable.
Angles steeper than what would be necessary for slope failure to occur during soil staturation conditions.
Each would most likely call for some means of mechanical anchoring into the soil or rock below.
Screw anchors and rock anchors come to mind --- Oh, there's super glue.
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
You need to first define your loadings and then run the analysis. You can't a priori say whether a thrust block is needeed or not, regardless of slope. An experienced pipeline engineer might be able to provide you with some rules of thumb but he is going to ask you what the loadings are.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
thread378-342040: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
Independent events are seldomly independent.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.
RE: WHEN IS AN ANCHOR BLOCK NECESSARY ? WE ARE DESIGNING A NATURAL GAS PIPELINE.