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Construction sequence - tunnel
Posted 4 sept. 2013, 10:37 UTC−4 Geometry, Structural Mechanics Version 4.3b 1 Reply
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Hi everybody!
I'm playing with tunnel construction process. Mainly, construction process can be divided into two repeatable steps:
1. excavation
2. lining installation
I'm modelling construction of convention tunnelling process (excavation e.g. by roadheader) and sprayed concrete as a lining.
After excavation, surrounding soil is deformed which is the first step of my calculations. After it, on a deformed tunnel walls concrete is sprayed to form lining. I want to create quite realistic model so it's necessary to use solid element to model it instead of shell elements.
My question is how to include soil deformation during installation of tunnel lining. I tried to use initial strain state but it cannot be used as solid elements which form tunnel lining are inactive in previous step (excavation). The only way is to transfer strains from tunnel wall to tunnel lining.
Anyone have any suggestion how can i do it? including that tunnel lining is made from solid elements?
Thank you in advanced
I'm playing with tunnel construction process. Mainly, construction process can be divided into two repeatable steps:
1. excavation
2. lining installation
I'm modelling construction of convention tunnelling process (excavation e.g. by roadheader) and sprayed concrete as a lining.
After excavation, surrounding soil is deformed which is the first step of my calculations. After it, on a deformed tunnel walls concrete is sprayed to form lining. I want to create quite realistic model so it's necessary to use solid element to model it instead of shell elements.
My question is how to include soil deformation during installation of tunnel lining. I tried to use initial strain state but it cannot be used as solid elements which form tunnel lining are inactive in previous step (excavation). The only way is to transfer strains from tunnel wall to tunnel lining.
Anyone have any suggestion how can i do it? including that tunnel lining is made from solid elements?
Thank you in advanced
1 Reply Last Post 4 sept. 2013, 16:42 UTC−4
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Posted:
1 decade ago
I figured out that maybe the solution is to use "general extrusion" to map displacements of the tunnel walls and in next step to use it as BC (prescribed displacement) for lining elements. This solution seems to be good however, obviously prescribed displacements generate stresses in the elements. In my case this is wrong because it is initial step, right after installation. Stresses are generated just by self weight of tunnel lining elements.
Does anybody know how to prevent from generating stresses by BC (prescribed displacement)?
Thanks!
Does anybody know how to prevent from generating stresses by BC (prescribed displacement)?
Thanks!