Proceedings of the
9th International Symposium for Geotechnical Safety and Risk (ISGSR)
25 – 28 August 2025, Oslo, Norway
Editors: Zhongqiang Liu, Jian Dai and Kate Robinson
On the Development of NEN8994: Assessment of Existing Sheet Pile and Quay Walls Based on Past Service Performance
1Safe and Resilient Infrastructure Department, Deltares, Netherlands.
2Port of Rotterdam Authority, Netherlands
3Reliable Structures, TNO, Netherlands
ABSTRACT
A historyof good past service performance can help to safely extend the service life of existing structures. However, reliability assessmentsaccounting for past performance can be time consumingwhenevaluating the remaining service life of earth retaining structures such as sheet pile walls and quay walls. Therefore, a national standard NEN8994 is currently being developed in the Netherlands which enables a semi-probabilistic safety assessment. The code should ensure safe life extension of existing sheet pile and quay walls and should account for the effects of survival under lifetime loading. This article discusses the factorsthat affect reliability and thus remaining service life over time and addresses the aspects and conditions relevant to responsible assessment of safety, including proven strength.
Keywords: Assessment of existing structures, Past service performance, Reliability, Code development.
