Ultimate bond stresses from pull out testing of soil nails, Dinnmore to Goodna, South-Eastern Queensland

This paper presents results of pull out tests on soil nails to assess ultimate bond stresses of residual clay soil, alluvium, weathered rock and embankment fill on the Ipswich Motorway Upgrade – Dinmore to Goodna (IMU – D2G) project. Vertical sacrificial soil nails were ‘pulled out’ or loaded to failure in a range of materials to assess bond stresses for design and construction of soil nail walls up to 13 m high. Testing was undertaken in materials for which there are no known published records of bond stress, including alluvium of the Brisbane River bank, historic fill of parts of the former Ipswich Motorway embankment and soil and rock of the Ipswich Coal Measures. This paper aims to share some of the ultimate and mobilised bond stress results obtained on the IMU – D2G project.