Bedding module

The bedding module  is a system parameter in structural engineering and is used for approximate consideration of the flexibility of the subsoil in the static calculation of foundations and foundation slabs using the bedding module method (spring model). For the sake of simplicity, it is assumed that the settlement dimension at each point of the foundation base is proportional to the base normal stress that acts at this point. ${\displaystyle k_{s}}$

This approach was first developed by Emil Winkler (1835 to 1888) in order to calculate the deflections and stresses of railway tracks ("Winkler bedding ").

The bedding module is accordingly a spring constant and is defined by:

${\displaystyle k_{s}={\frac {\sigma _{0}}{s}}}$

With

• the bedding module in M N / m³ ${\displaystyle k_{s}}$
• the normal stress in the base in MN / m² ${\displaystyle \sigma _{0}}$
• the settlement dimension in m. ${\displaystyle s}$

See also

• Stiffness modulus

Norms and standards

• DIN 18134 - plate pressure test
• DIN 4018 - subsoil; Calculation of the bed pressure distribution under surface foundations

Individual evidence

1. ^ Karl-Eugen Kurrer : The elastic bedded beam . In: History of structural engineering. In search of balance . 2nd, greatly expanded edition. Ernst & Sohn , Berlin 2016, ISBN 978-3-433-03134-6 , pp. 102-109 .