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What is Geotechnical Engineering? (Definition, Types and Salary)


Geotechnical engineering is an area of civil engineering that focuses on the engineering behaviour of earth materials. Using the principles of soil and rock mechanics, this subdiscipline of geological engineering uses knowledge of geology, geophysics, hydrology and more.

As well as civil engineering, geotechnical engineering is also used in fields such as coastal engineering, offshore construction projects, mining, military and petroleum. While the fields of geotechnical engineering and engineering geology have overlapping areas of expertise, engineering geology is closely tied to geology while geotechnical engineering is aligned to civil engineering.

Geotechnical engineers use their knowledge to determine the chemical, mechanical and physical properties of soil and rock for the design of earthworks, foundations and retaining structures. A site investigation of ground conditions is used to determine the depth of foundations, while earthworks may include embankments, channels, bunds and tunnels, and retaining structures include retaining walls and earth-filled dams.

Offshore geotechnical engineering is concerned with structures away from the shore, such as oil platforms, wind turbines structures, artificial islands and subsea pipelines. Offshore engineering is more expensive than onshore, with a wider range of geohazards and greater environmental and financial consequences as a result of failure.


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What does a Geotechnical Engineer do?

Geotechnical engineers use their knowledge of rock and soil to assess the risks and solve problems on a range of infrastructure projects. These professionals test and analyse soils and rocks to support design and construction while assessing potential risks including landslides, rock falls, sinkholes and earthquakes.

By assessing natural hazards, a geotechnical engineer designs plans and undertakes appraisals for onshore and offshore projects. The work of a geotechnical engineer can include:

  • Site appraisals and investigations
  • Geological and hydro-geological characterisation
  • Ground improvement and soil stabilisation
  • Excavations, earthwork creation and slope engineering
  • Foundation and retaining wall engineering
  • Temporary works and support systems
  • Ground monitoring and instrumentation
  • Drilling feasibility studies
  • Subsidence and underpinning engineering
  • Road and pavement subgrade testing
  • Risk assessment and monitoring

Geotechnical engineers create detailed reports to share the results of both on-site and laboratory-based testing. These reports are tailored to meet the specific needs of a project and include design parameters and advice for the construction of a range of man-made structures.

As well as providing consultancy services covering areas such as slope stability and load-bearing capacities for different materials, these engineers undertake research and development activities to improve methodologies, equipment, materials knowledge and analysis covering entire lifecycles. 


Humans have used soil for buildings, foundations, burial sites, irrigation and flood control for thousands of years. Early examples of dykes, canals, and dams date back to at least 2000 BCE in Egypt, Mesopotamia and the Fertile Crescent among other places. The expansion of cities led to the growing use of footings and foundations, but it wasn’t until the 18th Century that soil design began to take on a theoretical and scientific edge.

Early scientific approaches were begun in order to tackle foundation-related problems such as that see with the Leaning Tower of Pisa. This included the development of earth pressure theories for retaining walls, information on the natural slope of different soils and a rudimentary soil classification system based on material weight.

Many of these early breakthroughs have been superseded by later developments in soil mechanics and geotechnical engineering, such as theories for the bearing capacity of foundations, strength and stress-strain behaviours, the peak strength of soils, volume change behaviour and more. 

Where do they Work?

Most geotechnical engineers work in the private sector, employed by engineering or construction companies and consultancies. Geotechnical engineers also work in industries such as energy and marine, where they use their skills and expertise to ensure the safety and stability of a range of structures.

Geotechnical engineers make site visits, but also work from laboratories and offices to assess soil and rock samples and create reports. 

Types of Geotechnical Engineering

Geotechnical engineering can be split into three types:

1. Soil Mechanics

Applying engineering mechanics to soils to assess their properties as well as investigating dynamics, fluid mechanics, kinematics and material mechanics.

2. Rock Mechanics

Engineering the properties and mechanics of rocks – including the application of dynamics, fluid mechanics, kinematics and material mechanics.

3. Foundation Engineering

This brings together geology, soil and rock mechanics, and structural engineering for the design and construction of foundations for a range of civil engineering projects. This field involves predicting the performance of foundation soil and rock to a load imposed by a structure, while considering performance, economy and safety.

How to Become a Geotechnical Engineer

Most people entering careers in geotechnical engineering will have first attained a degree in engineering geology, geology, geophysics, geoscience, geotechnology, mineral or mining engineering, or civil engineering with a bias towards geotechnology.

Other professionals may have undertaken an apprenticeship degree or joined a graduate scheme at a large employer.

Some employers will seek those with postgraduate qualifications such as a Masters (MSc) in subjects such as soil or rock mechanics, engineering geology, hydrogeology, foundation engineering or geotechnical engineering. Geotechnics is a civil engineering specialisation at Master’s level.

The Institution of Civil Engineers (ICE) and the Institute of Materials, Minerals and Mining (IOM3) can also offer routes onto geotechnical engineering for those with a background in civil engineering or science.

Whichever geotechnical engineering programme you choose, it is important to gain work experience too. This can be gained via a placement during your studies or an internship at a consultancy, construction company or engineering firm.

As with all engineering disciplines, professional development is an important part of this profession, allowing you to take on more advanced and better-paid roles. This will often include working alongside a mentor during the early part of your career while you work through a development plan and gain professional qualifications. Chartership is also a possible route for engineers via accredited training linked to a professional body. Membership of a professional body will also allow you the opportunity to network and gain knowledge from fellow professionals.

Work and Responsibilities

Geotechnical engineers are responsible for a variety of tasks, requiring a mixture of expertise and soft and hard skills. These responsibilities include:

  • Creating, building and maintaining relationships with customers and other professionals involved in each project
  • Maintaining safety standards while working on-site
  • Taking account of costs when making technical recommendations

Projects will often be split into research, on-site assessment and reporting phases, each with their own distinct tasks and responsibilities, as follows:

1.  Research Phase

  • Study maps and photographs of a site taken over time
  • Assess construction plans to check their feasibility based on the site
  • Investigate potential risks or geological hazards for the site
  • Develop ground models and plan field investigations

2.  On-site Assessments

  • Collect and analyse samples of rock, soil, groundwater and other materials
  • Supervise other professionals
  • Solve any technical issues as they arise, for example unexpected structures at drill sites
  • Monitor conditions during and after construction to ensure structures are stable

3.  Reporting

  • Collating data collecting on site with original research information
  • Producing geotechnical calculations, drawings and computer models to interpret and present data
  • Creating a report outlining recommendations for the use of a site

Salary and Working Hours

Salaries for geotechnical engineers differ depending on location, employer and experience. However, rates of pay generally increase as your knowledge and skills grow, with guidelines pointing to a graduate starting salary of between £18,000 and £28,000 per year in the UK. This rises to £26,000 to £36,000 with a few years of experience and then reaching £40,000 to £60,000+ for senior, chartered or master engineers.

With regards to working hours, geotechnical engineers tend to work longer hours during the earlier stages of a career, but as experience grows and less time is spent on-site, a more standard 9-5 working pattern is more usual. Most geotechnical engineers work full time hours, with part-time working being rare in this profession. 

Benefits of Becoming a Geotechnical Engineer

Although the work of a geotechnical engineers can be demanding due to responsibilities including overseeing health and safety of others and having to make decisions with potentially high-value consequences, there are also a number of benefits to this profession.

Geotechnical engineers may be given the opportunity to travel, including overseas and will be able to directly use their skills, knowledge and experience in the role. There are lots of opportunities to meet new people and work with a range of different professionals.

Knowledge and Skills

Geotechnical engineers need to be able to demonstrate a range of knowledge, skills and traits, including:

  • Knowledge of the principles of soil and rock materials
  • Knowledge of water, ground and soil monitoring techniques
  • Able to apply technical knowledge to analysis and problem solving
  • Able to maintain an oversight of budgetary requirements
  • Able to adapt to working on different projects and with different teams
  • Capable of both working as part of and leading a team
  • Able to build and maintain client relationships
  • Good communication and reporting skills
  • Good attention to detail
  • Sound judgment and a ‘can-do’ attitude
  • Flexibility regarding travel to sites (sometimes including overseas)
  • Passionate about the natural environment and happy to work outdoors as required

Why Geotechnical Engineering is Important

Geotechnical engineering is important as it helps prevent damage to other buildings and structures as a result of subsurface conditions. The calculations and tests undertaken by these engineers help ensure safety and stability for structures and can mitigate against earthquakes, slope stability shifts, ongoing earth settlement and more. 


Geotechnical engineers determine the physical, mechanical and chemical properties of soil and rocks to assist with the design of earthworks, retaining structures, foundations and tunnels. They also monitor site conditions, earthwork and foundation construction, evaluating risks and predicting and mitigating against potential damage caused by natural hazards such as earthquakes, volcanic eruptions, avalanches, sinkholes, and mud or landslides. Site investigations are coupled with laboratory testing of soil and other samples using a range of testing and assessment methods. Working with both on and offshore projects, these engineers also undertake geologic and geophysical mapping when engineering geological conditions. 


What is the Average Salary for a Geotechnical Engineer?

Salaries for geotechnical engineers differ according to location, experience and employer, which makes it difficult to pin down an exact average salary. However, sources agree that, in the UK at least, the average salary is somewhere between £31,00 and £38,000 per annum.

As of 2022, the average salary for a geotechnical engineer in the UK has been reported as:

  • £31156 (
  • £34910 (
  • £37573 (

Is Geotechnical Engineering Hard?

Yes, geotechnical engineering is hard as it requires a great deal of education and training. However, with the right application it is possible to master the profession and gain entry to a challenging yet rewarding and important career.

Can a Geologist become a Geotechnical Engineer?

A geologist would need to retrain to become a geotechnical engineer, although there is plenty of cross-over between the two professions, which could make this easier. Geologists need to have an understanding of soils, rocks and other materials from a scientific perspective, while geotechnical engineers tale their knowledge of matters such as soil and rock mechanic, geophysics and hydrology and apply them to engineering and environmental projects.

Is Geotechnical Engineering a Good Career?

Geotechnical engineers are in demand as the global population continues to increase and environmental issues such as flooding become increasingly common. When starting out, these engineers will tend to work on less complex projects, building up knowledge and experience ready for more challenging work later.

Geotechnical engineers tend to specialise in specific areas as they grow in experience, focusing on particular infrastructures such as railways, roads or water. These engineers also work with renewable energy, offshore and onshore oil and gas, nuclear power, and more.

More experienced engineers can find themselves moving towards a management role, more strategic planning or even leading a company of their own.

How long does it take to become a Geotechnical Engineer?

The time taken to become a geotechnical engineer depends on where you are based, where you study and what level of education you want to attain before entering the workplace. For example, are you going to explore an apprenticeship, take a university degree or work on towards a Master’s or PhD? However, generally-speaking it takes 3-4 years to reach the basic requirements to start a career as a geotechnical engineer. 

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