Case Study Of Railway Embankment Stabilisation Works At Moor Park Station With Progressive Slope Failure

Two railway embankments which are located next to Moor Park station, approximately 30 km northwest of London, support the southbound and northbound London Underground Metropolitan Line tracks. The embankments were identified as showing various signs of progressive slope failure and required implementation of stabilisation works. The earthworks originally constructed in the late 19th century were subject to embankment widening works in the 1940s and have had a complex history of construction and modification with evidence of past instability.

For the remedial works, there were a number of geotechnical and construction issues which included highly variable ground conditions, environmentally sensitive sites surrounding the embankments including a man-made river and existing rail structures along the embankments. This paper describes the measures taken to manage the geotechnical risks.

The adopted design criteria, the slope stability assessment and the proposed remedial works which include a bored pile wall with precast concrete capping beam, a discrete bored pile wall, a slope regrade and toe berm are presented in this paper. For the design and slope assessment, modified soil strength parameters for high plasticity index cohesive embankment fill or weathered London Clay identified from soil investigation was used.