CAPABILITY STATEMENTS
FOUNDATIONS AND RETAINING STRUCTURES

1. RELEVANT EXPERTISE

Dr Philip Pells has played a major role in the development of design parameters and design methods for foundations founded on rock, including high capacity socketed bored piles. In 1978 he was leader of the group within the Australian Geomechanics Society which developed a classification system for the shales and sandstones of the Sydney region, and associated foundation design parameters. In 1998, together with Mr Garry Mostyn, another of PSM’s Principals, the system was updated. It is now used by all practitioners in the Sydney area for foundation design in the sandstone and shales.

Garry Mostyn, who was a Senior Lecturer at University of NSW, has had extensive experience in the design of retaining walls, both for residential developments in the Sydney region and for marine and infrastructure developments throughout Australia. Together with Philip Pells he played a major role in the new East Arm sheetpile wharf structure in Darwin, and was one of the experts in relation to the collapse of the sheet pile retaining structure in Cooks River, Sydney.

Dr Gareth Swarbrick was also a Senior Lecturer at University of NSW and amongst his skills includes expertise in relation to reactive soils.

Strath Clarke has specialised in the design and analysis of foundations on soils, particularly soft clays. He is one of Australia’s leading specialists in the use of Pressuremeters and Piezo-cones in assessing design parameters for soil foundations.

David Piccolo has worked closely with Garry Mostyn and Strath Clarke on the design and forensic analysis of several major retaining wall projects in new industrial developments in the western areas of Sydney. They have also developed special expertise in the design of very large, single pole, transmission towers.

Derek Anderson has been responsible for design and construction advice on several soil nail support projects including the box cutting for Olympic Station at Homebush, and was responsible for foundation design and associated rail tunnel monitoring of a tower development directly above four of the rail tunnels in George Street, Sydney.

2. SELECTED PROJECTS

2.1 City Basements

463 George Street, Sydney Support for deep basement, design of pad and bored pile foundations
Lobana Towers, Pitt St, Sydney Footing design parameters, permanent anchors for basement sidewalls
Transgrid Sub-station, Ulitmo, Sydney Design of high capacity permanent ground anchors for support of excavation sidewalls, footing design parameters, construction supervision
Village Cinema Site, Sydney Design and construction advice for 34 m deep basement adjacent to rail tunnels beneath George Street
420 Pitt Street, Sydney Complex reinforcement and underpinning of foundations of adjacent structures.
George Street, Sydney Analysis of new tower structure above four rail tunnels. Installation of real time monitoring of the rail tunnels during basement excavation and tower construction.

2.2 Soil Nails Retention

Retaining and slope stabilization by “soil nailing” comprises the use of untensioned, fill column grouted of reinforced shotcrete, and designed to provide an excavated vertical, or sloping, face with the requisite factor of safety against instability.

The retained material may be soil (fill or natural) or may be weathered rock wherein structural features/joints shears and bedding planes) control the kinematics of failure. Support is usually provided progressively, in a top-down form of construction, as the excavation is made.

Olympic Rail Station, Homebush, Sydney 1m to 8m high vertical faces, about 100m long, in a profile varying from about 1m of residual soil, through 3m of extremely weathered shale, to slightly weathered shale. The dowels comprised up to 5m long HDPE sheathed 24mm bars, connected to the SFR shotcrete using strips of galvanised “trench mesh”. Drainage behind the shotcrete comprised geofabric covered egg-crate stripdrains at 2m centres. Design loading was based on a ubiquitous design prism of rock calculations from joint defect mapping.
Inner City Hospital, Sydney 2m to 6m high vertical faces of total length about 150m, in residual clays and extremely weathered shale. The design concept was similar to Homebush Station.
Devlin Street Underpass, Ryde, Sydney Very similar to the Inner City Hospital in geological profile and design.
Jenolan Caves, NSW Soil nail supported batter slope up to 8m high in colluvial soils.
The Sanctuary, Gosford, NSW 5m to 1m high cut face in highly to extremely weathered sandstone. Dowels comprised galvanised 24mm reinforcing bars designed having a 5mm sacrificial steel allowance. The face membrane comprised mesh reinforced plain shotcrete.

2.3 Other Structures

East Arm Wharf, Darwin Analysis of stability and displacements of 20m high sheet pile wall structure, analysis of passive toe resistance in jointed phyllite.
Neutron Guide Hall, Lucas Heights Very large scale cable jacking tests to assess mass modulus of the sandstone to allow accurate calculation of settlements in an extremely low tolerance facility.
Andoom Dump Facility, Weipa Investigations of collapse of in-ground dump facility comprising 8m high anchored concrete retaining walls.
Yandicoogina Bridge, Pilbara, WA Advice in regard to stabilisation of rock against sliding and toppling beneath Pier foundation on edge of near vertical side of gorge.