What are the major challenges in the piling foundation industry in the region? What steps must developers and engineering firms consider in overcoming these challenges?
The most common geotechnical issue found in the MENA region is the case of ‘unforeseen ground conditions’ which is often the results of too little investment in the site investigation campaign. Leading onto the piling foundation industry in the GCC, the biggest challenge that we must overcome is the lack of geotechnical representation on projects. Clients typically rely on their consultant to address technical challenges. Only few consultants employ Specialist Geotechnical Engineers and the foundation design is routinely forced on the site investigation contractor who is requested to produce a ‘fit all possible buildings’ design without being given loads and geometrical information specific to the project. This means that essential soil-structure interaction mechanisms and group effect behaviours are ignored in their analysis. Our industry must address this, starting with making sure that every tall building project has access to a Specialist Geotechnical Consultant to avoid over-reliance on site investigation contractors. Approving authorities should also have recourse to a Geotechnical Engineer to review the foundation and shoring designs.
There is a general impression that traditional piling techniques are still prevalent in this region. Is that so, in your opinion? And if so, is that an advantage or a disadvantage for the sector?
The piling techniques being used regionally are sound, what is prevalent are outdated foundation design techniques. We should provide our talented Geotechnical Engineers a real opportunity for producing efficient foundation designs. Dubai is an international leader in construction and innovation and has a duty to apply this vision to tall buildings foundation systems. Where applicable, sharing building loads between the raft and the deep foundation piles, like the Combined Pile Raft Foundation system, would allow Geotechnical Engineers to make a real difference.
Across the globe, with newer technologies and innovative architectural possibilities, there arises the need to address complex design requirements. How does the geotechnical fraternity address these needs?
Globally, a popular technology available to the geotechnical community is the Combined Pile Raft Foundation (CPRF) system. Its robust design procedure allows for sharing building loads between the ground bearing raft and deep foundation piles, located under the structural elements carrying the higher building loads. This design approach is controlled by settlements in making sure that building foundation will not settle more than what the building can tolerate (which is different for every structure). CPRF systems provide an economical foundation solution which reduces dramatically the quantities of construction materials required to achieve a safe foundation with multiple redundancies. This system has already been proven in the GCC as Dubai pioneered its successful implementation starting with the Emirates Twin Towers and Burj Khalifa. Since the system works, why not offer it to Developer Clients as opportunities for cost savings, carbon footprint reduction and safer construction sites due to the reduced construction programmes?
However, for the successful implementation of a CPRF system, the design effort is higher than what our industry currently routinely allows for traditional fully piled solutions. The input of a specialist Geotechnical Consultant is indispensable and his work should be checked by an independent third party reviewer (also expert in Geotechnical Design).
What are the current market trends in the geotechnical engineering industry globally and within the GCC?
I am very positive about the future of Geotechnical Engineering in the GCC. It is becoming well know that our discipline is a standalone speciality that is not simply a sub-set of structural engineering. Clients are more aware of the risk and opportunities embedded in Geotechnical Engineering and are ready to invest more at the front end to reduce their construction costs and mitigate their risk adequately.