What the ground does to buried concrete here
Dig a basement in Dubai Marina and you reach groundwater quickly. That water carries chlorides, which travel through the cover concrete toward the reinforcement, and sulphates, which react with the cement paste itself. A pile or a raft sits in that water for the whole life of the building, with no chance of inspection.
So the first decision is not strength. It is permeability. Our piling and substructure mixes for the Marina are designed around a GGBS blend and a low water/cement ratio, which gives a denser paste that slows chloride ingress and resists sulphate attack. The cover depth and exposure class come from your consultant's specification, and we design the mix to meet that class.
Element by element on a Marina tower
Bored piles take a piling mix: high workability so it flows around the cage through a tremie, with enough cohesion not to segregate under water. The transfer raft above them is usually a large continuous pour. A 1,200 m³ raft is 100 truckloads of 12 m³, so the pour plan, the number of pumps and the retarder dose all get agreed before the first truck leaves.
Above ground, columns, core walls and transfer slabs move to a superstructure mix. Exposure drops, but pumpability and early strength matter more as the frame climbs. Our boom pumps reach from 43 m to 57 m; beyond that height the job needs a placing boom on the structure and a static line.
Heat, distance and the clock
The plant in Al Quoz is about 11 km in a straight line from the Marina. Sheikh Zayed Road and Al Sufouh Road are the usual approaches, and peak traffic lengthens the trip, so mixes travelling here carry a retarder set for the expected time in the drum. In summer, project specifications cap the placing temperature, which pushes large pours to the night and early morning. Tower management and the master developer often decide when trucks may enter, so check with them before fixing a pour date.
Questions from Dubai Marina sites
- Why use GGBS in Dubai Marina foundations?
- GGBS blends produce a denser paste with lower permeability, which slows chlorides reaching the steel and improves resistance to sulphates in the saline groundwater.
- How do you handle a raft pour of several hundred cubic metres?
- We plan it as a continuous pour: truck count from the volume (12 m³ per truck), pump positions, and a retarder dose that keeps each load workable through traffic and placing.