Geotechnical Engineering

Geotechnical engineering is a branch of civil engineering and studies the behavior of earth materials. A geotechnical engineer investigates subsurface materials, determines the physical and chemical properties of such materials, designs structure foundations.

A site investigation of soil and rock properties in the area where a structure has to be build is where a geotechnical engineer will start his work. He can then design the type of foundations required for the structures that have to be built. Geotechnical engineers have to assess the impact a certain location can have on the materials and methods used to build a structure.

One example of a geotechnical project was carried out for the construction of the Enlarged Cotter Dam, in the Cotter River valley. This new, 80 meters high dam will be Australia’s third largest concrete gravity dam. The geotechnical engineers working on this project had to overcome challenges related to working at height, with only rope access in order to map rock defects and other geological problems. They drilled shot holes and placed explosives in order to obtain data for seismic refraction surveys. The data gathered can reduce significantly the cost of the dam. The efficient foundation excavation meets all dam safety requirements. Since the area is a favorite leisure destination, engineers have tried to minimize the impact of their work on the site so as to reduce noise. They have also shared their geological and archaeological findings with the community during a National Science festival.

Geotechnical engineering is involved in the design and construction of wharves and marinas. Marine geotechnical engineering deals with seabed materials which are composed of rock and water. Structures, such as piers or fixed-bottom wind turbines, are fixed in the seabed. Floating structures are anchored to remain fixed relative to a geotechnical anchor point. Geotechnical engineers can find jobs in coal operations such as the ones based in New South Wales, Australia. They can offer advice on geotechnical issues related to mine planning. A geotechnical engineer can identify geological and geotechnical hazards and develop plans for dealing with such hazards. He can also map the shaft, tunnel or underground excavations. Geotechnical engineers are needed to design roof and rib support in mines, monitor the roof stability or control and manage the strata. The processing and assessment of all data related to such an underground coal operation can be part of the job for a geotechnical engineer.

Geotechnical engineers are involved in the construction of the Australian Marine Complex Service and Supply Base in Western Australia. This new wharf will be able to accommodate vessels of up to 200 m in length, while the associated four hectare staging area will accommodate up to 200 truck trailers. The marine works for this project involve sheet piling, mooring structures and seawall construction. The project involves other engineering expertise such as civil engineering, transport engineering or electrical engineering. The civil works involved in the project include earthworks, fencing, roads and pavements, lighting towers and other structures. Electrical services include communications, cabling, earthing and testing. Hydraulic engineering expertise will be used for the potable water system, sewer and fire water.