Description

Concerns the alteration of concrete in tunnel plugs by dissolution of calcium hydroxide (Portlandite) and calcium-silicate-hydrate (CSH) and precipitation of secondary hydration products as well as ettringite, brucite and Friedel salts..

SKB Number

SKB FEP Number

Pg12

Main Category

Main category for FEP

Internal process

System Component

System component to which the FEP applies

Tunnel plugs

Handling

Explanation of how the FEP is treated

Intact canister, Resaturation/ "thermal" period: Separate modelling of concrete degradation. Intact canister, Long-term after saturation and "thermal" period: Separate modelling of concrete degradation.

References

Bibliographic references to obtain more information

SR-Site Buffer, backfill and closure process report, TR-10-47, Section(s) 2.4.3, 5.4.4