Upward vertical soil stiffness [KLT]

Calculations of Upward vertical soil stiffness

NEN3650-1:2012

The Upward vertical soil stiffness is only calculated for the NEN3650-1:2012 calculation methodology. The soil range of importance for the Upward vertical soil stiffness is from ground level to the top of the pipeline. There are two formula's for trench installation: one  for sandy soil types and one for clayey/peaty soil types and there is one formula for non-trench installation. A trench installation is either 1)Trench uncompressed fill or 2)Trench compressed fill and a non-trench installation is either 3)Boring or 4)HDD.

Formula_KLT

Sandy:
Formula_KLT_sandy

Clayey/peaty:
Formula_KLT_clayey

Non-trench:
Formula_KLT_nontrench

kv,top

Upward vertical soil stiffness

Qp

Ultimate top soil reaction

E

Effective Young's modulus calculated for range from ground level to the top of the pipeline, using depth at top of pipe (given in N/mm2, factor 0.2 and 0.25 are not dimensionless)

D

Outer diameter of pipeline

H

Height of soil coverage on top of pipeline

m

Formula_KLS_m_new

l

Formula_KLS_l

λ

Formula_KLS_lambda

ν

Formula_KLT_nu

φt

Angle of internal friction (averaged over range from ground level to the top of the pipeline)

Epipe

Young's modulus of pipe material

Ib

Formula_KLS_Ib

Di

Inner diameter of pipeline

Info The formula for kv,top has been adapted for the calculation model used in Ple4Win, also see the comment on page 134, NEN3650-1:2012, C.4.3.2.


Last changed: 14/09/2016