Abstract:
Delivering deep diaphragm wall and barrette foundation systems for large-scale infrastructure projects presents a range of practical and risk management challenges. Large panel volumes, complex reinforcement designs and variable ground conditions require careful planning and precise execution. This paper shares insights from two major infrastructure projects involving diaphragm wall and barrette foundations, highlighting construction methods, digital tools and quality control processes from a contractor’ s perspective. The works spanned a combined alignment length of approximately three kilometres, with panel thicknesses between 1 to 1.2 metres and excavation depths ranging from 20 to 45 metres.
Prior to construction, numerical modelling using Plaxis 3D was used to assess trench stability, confirm panel dimensions and define support conditions critical for trench integrity and safety. It was also used to define the performance requirements for bentonite slurry, which was tested regularly on site to ensure compliance, as a temporary support fluid.
Real-time instrumentation systems such as TIO and B-Tronic tracked excavation progress, trench verticality and ground conditions. These technologies supported production planning and allowed for early identification of constructability issues. A 3D structural model was used to facilitate rebar cage fabrication and improve visualisation for identifying potential rebar clashes or detailing issues prior to fabrication. Digital pre-installation inspections verified cage quality and ensured compliance with the design, detailing and specifications, reducing the likelihood of installation issues. The use of a superlatch system streamlined cage splicing and provided several HSEQ benefits.
Concrete works were monitored using live digital tools to track progress and confirm placement compliance. Site data was consolidated into Power BI dashboards, enabling real-time reporting, forecasting and communication with stakeholders.
This paper presents key aspects and lessons learned in constructability, risk mitigation, digital integration and quality control, demonstrating how early planning and connected systems can enhance the execution of diaphragm walls and barrette foundation systems in complex infrastructure environments.
Keywords: diaphragm wall, barrettes, deep excavation, smart execution, digital tools, quality control.