The $3.3 million(U.S.) Jumeirah Vehicular Tunnel waterproofing project was completed in April. The 1,400m tunnel is the only link for vehicles between Jumeirah Palm Island and the crescent areas surrounding it at the spectacular palm island complexin Dubai.
The waterproofing system, designed and executed by BMC Gulf Contracting LLC, involved the installation, welding, and testing of a high-density polyethylene (HDPE) membrane. The 2mm-thick membrane constitutes the main line of defense against seawater ingress into the tunnel.
The choice of a suitable geomembrane material, a critical aspect of the tunnel system, was based on the membrane’s high puncture resistance, its high elongation factor, and its chemical and UV resistance, according to project managers.
The tunnel is the only connection for vehicles between the Palm Island and the crescent surrounding it and has a length of 1,400m, a width of 38m, and a height of 9m. The lowest point at its center is 30m under seawater level.
The tunnel is an assembly of 40 segments, with 4 compartments each. Every compartment is waterproofed to prevent any potential leakage from spreading across the structure. All compartments are connected by external HDPE waterstops, with reinforced ribs embedded into the concrete. Four additional defense lines were used to secure the watertightness of the tunnel, including internal PVC waterstops, swellable seals, and reinjectable PVC hoses.
Once the installation of the waterproofing system was completed, a nonwoven geotextile layer was used to protect it from damage that might have occurred to the membrane during backfilling around the tunnel.