Embedding a Collaborative Culture
From the outset, it was clear that with the number of sites and stakeholders involved in the project, collaboration would be the key to successful delivery. RIMOND CIMOLAI put forward and championed a collaborative culture, including everyone in the decision-making so that the best options for everyone involved on the project could be taken forward. This was useful for coordinating works between projects, as well as managing logistics effectively, such as site deliveries, equipment, materials storage, groundworks, temporary works, and health and safety concerns.
Enabling End-to-end Digital Solutions
To address the complexity of the project, an end-to-end digital methodology was adopted from the early stages. This meant that every aspect was digitally engineered before it was built on site, down to the last nut and bolt. Using information-rich 3D modelling, the design could be better communicated, understood, and coordinated thanks to the enhanced visualization that a digital approach enabled. RIMOND CIMOLAI created a digital wireframe model to integrate and coordinate all design disciplines, from the geometry of the structure to the MEP systems. From this model, BIM models were created for all the different disciplines, which enabled enhanced coordination between the supply chain and stakeholders.
Undertaking Robust Risk Analyses
Another benefit of a digital approach was the creation of visualized method statements. Because the construction was so complex and space so tight, RIMOND CIMOLAI undertook extensive risk analysis by creating step-by-step method statements using 3D visualizations of each work activity. This ensured that the design intent was clearly communicated to the site supervisors and workforce and allowed robust planning to be undertaken to reduce the safety risks as far as practicable.
Implementing Modern Methods of Construction
To overcome the congestion and space limitations on site, as well as to accelerate the construction schedule, RIMOND CIMOLAI proposed the use of prefabrication, preassembly, and off-site manufacture wherever possible. Prior to manufacture, the steel sections were optimized at the factory so that the deliveries could be rationalized into as few trips as possible. Larger sections of steel were preassembled to the maximum size and weight permitted by the roads on site and in accordance with the limitations of the lifting equipment. The preassembled sections included MEP services integrated within, so that installation was much quicker and safer. This innovative use of modern methods of construction reduced the works at height and the amount of work required on site, increased productivity and safety, and fast-tracked the schedule.
Engineering Innovative Construction Methods
The site congestion and local conditions (such as the tunnel) also affected the construction methods used. To overcome this, modular temporary structures were built to assist with installing components at height. They could be dismantled to save space if needed, as well as re-used throughout the construction process to save waste. Another issue was the steel erection in such a confined space. Together with Maffeis Engineering and Robert Bird International, RIMOND CIMOLAI designed a steel erection methodology that enabled the 550-tonne crown of the dome to be built on the ground and then lifted into position, 45 meters above ground level. To achieve this, 18 strand jacks were installed on posts, which lifted the dome – and carried a total weight of 800 tonnes, including the temporary supporting equipment – into place while ensuring millimeter-precision. As the tolerance allowed was only three millimeters, this accuracy was crucial to the build. It was attached using 53 temporary connection brackets, and required engineers to monitor the process using GPS sensors throughout the night to ensure the perfect alignment.
Meeting Exacting Architectural Requirements
Achieving the architectural specifications required some innovative approaches. For the steel dome, RIMOND CIMOLAI undertook custom steel connection design utilizing advanced parametric form finding methods in order to provide circular steel pipes that were seamlessly welded to avoid visible joints along the curvature of the dome, while still providing the required structural integrity. Over 1160 individual curved steel sections were installed to create the dome, which required more than 13km of steel pipes.
For the 42 projector and 12 speaker enclosures, an advanced fabrication methodology was adopted. The design intent required aviation-level fabrication techniques of aluminium double curving, complex GFRC cladding, and automated moving components connected to the plaza’s overall BMS system.
In addition, the materials that made up the enclosures were designed to be integrated and assembled in a factory setting in Mexico. Due to the size of the enclosures once fabricated, the only aircraft that could accommodate them was the Antonov plane, which is the largest air carrier in the world. RIMOND CIMOLAI commissioned two flights from Mexico to Dubai using the Antonov plane to deliver the enclosures on time to the construction site for installation.
Supplying the World’s Largest Building Maintenance Unit
There was also the issue of ensuring that the BMU for the dome and its access system could be fabricated and installed as per the designer’s concept. RIMOND CIMOLAI undertook extensive engineering work so that the design could be fabricated and installed optimally on site. This meant ensuring that the design was feasible, could be fabricated in parts that could be easily transported to site without requiring too much storage, and planning the construction sequencing.
After 19 months of construction, the Al Wasl Plaza Dome became the crowning jewel of the Expo, as well as its stunning heart. The speed of progress on site was a testament to the success of the collaborative culture of the team, as well as the innovative, off-site construction and digital approaches adopted. The project set a blistering pace that is almost unheard of in the construction industry despite the many challenges faced, while providing the highest quality, consistency, and safety standards.
The project has been awarded a CEEQUAL Whole Team Excellent certificate with a score of 93.6% – which is the highest rated project in the Middle East to date. In addition, despite the large number of workers on site – 1000 laborers on a daily basis both on- and off-site in 24-hour shifts – RIMOND CIMOLAI were recognised for their excellent health and safety and worker welfare performance with awards for both aspects from the organizer, Expo 2020 Dubai.