Civil and Structural Engineering: some real life applications (Master’s students)
In February, Akil Jasm Major Project Design Manager and Robert Powell Senior Engineer, visited Bradford University to deliver a presentation on Sheet Piles in temporary works applications. Their audience consisted of 4th year MSc students who are engineers in the making.
Akil has been delivering talks at the university for a number of years now. Explaining the value of the talk, he said: “We aim to show the students the practical side of the theory learnt on their course, helping to demonstrate how the maths transfers into real-world practicality.”
Their presentation focused on temporary works, health and safety and sustainability. Groundforce are proud to support the development of students from the university; helping through similar talks to offer real-world context alongside the placement of many graduates after their time studying is complete. Here we take a look at just some of the areas covered during the talks:
What are Temporary Works?
In what is a very niche area of construction, Akil and Robert were keen to stress the importance of establishing an effective temporary works installation in preparation for the construction of permanent works.
Although temporary works cover a range of disciplines such as scaffolding and formwork, Groundforce’s main body of work involves delivering shoring solutions for excavations and ground support using sheet piling together with other equipment such as hydraulic braces and struts. In short, this means any temporary structure installed to exclude soil and water from an excavation below the existing surface in order to facilitate the construction of permanent works.
Our presenters acknowledged that the students may not be aware of the many instances where temporary works would be implemented, and this is almost certainly because the removal of temporary groundworks is inevitable to allow permanent structures to continue; the clue being in the word ‘temporary’. However, students were made aware that temporary works would have undoubtedly played a major role in the construction of many familiar structures, such as:
- Cofferdams
- Basements
- Swimming pools
- Car parks
- Tunnelling
- Retaining walls
Why provide ground support?
Robert and Akil presented ‘real-world’ examples of shoring and temporary works in action, from narrow trench support commonly used in utility projects, through to major projects where temporary works is provided to exclude sub-surface soil and water for cofferdams and complex multiple level strut designs for car parks and airports.
Health and safety is paramount in the modern workplace and no more so than in the construction sector. Our cohort of MSc students were informed that in 2020-2021, 30% of all workplace deaths were in construction with many fatalities occurring in and around excavations less than 2.4m deep where no shoring had been provided; a fact that shatters the notion that shallow excavations are less dangerous or less likely to collapse. The inherent dangers of inadequate shoring were made clear as our presenters showed videos evidencing how unsupported excavations can easily result in a major catastrophe.
Effective temporary groundworks comply with health & safety laws and help to protect the public and workers alike, as well as safeguarding existing structures. Contractors attempting to mitigate the cost of a project through neglecting temporary works may find themselves landed with significant legal and contractual repercussions if things go wrong.
The design process: some real-life applications
With students typically following theoretical and academic study during their MSc in Civil and Structural Engineering, Akil and Robert were able to enrich their learning experience with the practicalities of real-life applications; explaining that initial brief requirements involve gathering key information such as:
- Location and site contact
- Purpose of the excavation
- Size, shape and depth of the excavation
- Ground information (soil type, presence of groundwater etc)
- Surcharges and surrounding hazards (plant vehicles, roadways, buildings)
An in-depth analysis then follows, which considers soils adjacent to a structure that generate loads upon the support system, the plan dimensions and depth as well as consideration for any adjacent surcharges, such as buildings, railways and plant. Other considerations which fascinated the students on an academic level, included the use of:
- Limiting Equilibrium (the balance of active and passive soil pressures)
- Pseudo Finite Element Analysis (generating a design solution to calculate soil pressures that take into consideration the relative stiffness of the soil and support system)
- Advanced Finite Element Analysis
Sheeted Excavations and their variations
Having touched on the design process, a whistle-stop tour of the different configurations was discussed when using sheet piles in temporary works applications. Depending on the existing conditions, it was explained that cantilever, propped cantilever or multiple frame solutions can be employed depending on the prevailing site conditions.
The piling equipment used for installing the sheets again depends on the ground conditions which will dictate the type of piling hammer used. For example, it was explained to students that selection of the most suitable Excavator Mounted Vibrator (EMV) would vary depending if the ground conditions were granular or cohesive.
An enjoyable and informative presentation
Wrapping up the session, Akil and Robert talked about the work done back at Groundforce by the Major Projects team. Images were displayed showing some of Groundforce’s most prestigious undertakings using state-of-the-art hydraulic struts. This led to a discussion about load monitoring and how extreme temperature variations dramatically impact the loading of props and how load monitoring software provides live data and alerts from anywhere in the world.
All in all a most informative and enjoyable learning experience for both students and presenters. Akil and Robert would like to thank the University of Bradford for the opportunity to come along and share with students the role that Groundforce plays in temporary works applications. We look forward to continuing our relationship with the university to provide inspiration to students as they pursue their careers in Civil and Structural Engineering.