Old Oak Common Abutment Stability
CASE STUDY
Existing scenario: Raking pile remedial system at toe of abutment wall stabilising the existing abutment against geotechnical failure. System required demolition to facilitate installation of permanent works (new concrete abutment).
The design of the proposed ground anchors was carried out in accordance with BS EN 8081:2015 to resist the horizontal load that the raking pile system is designed to withstand (from record information).
The stability analysis of the abutment with the ground anchors wall was undertaken considering the surcharge from railway traffic on the bridge and behind the bridge. In accordance with NR/GN/CIV/025 section 11.2 (assessment) table 11.1, a rail surcharge load model (RA8) of 38kN/m2 was used in the analysis. The analysis took into account dynamic effects, eg. taction and braking forces.
The wall was analysed using the 3D Finite Element Method (FEM) assisted by Plaxis-3D software to reproduce the effect of every construction phase of the excavation works.
Design Delivery: The design was completed under the Form C process and complied with all relevant standards, including Network Rail, Eurocodes, BS EN 8081:2015, NR/GN/CIV/025, and EC7. It passed a Category 3 design check, and included a detailed inspection, testing, and monitoring plan within the Form C submission.