The mammoth operation to form the foundations of the 162 metre high structure saw a steady stream of 200 lorries arrive on the seafront site.
Construction started last summer on the £46.2m scheme designed by Marks Barfield Architects and Jacobs on the old West Pier site.
West Sussex contractor Mackley is in charge of the civils package on the project with Dutch steelwork specialist Hollandia set to erect the main steel mast.
The doughnut-shaped main observation pod will be built by French cable-car specialist POMA, which delivered the London Eye pods.
Site officials carefully staggered the pour timings to avoid congestion in the town.
An i360 statement said: “The trucks, which are coming from three different places, have staggered departure times so that they do not all arrive at the same time. So far this is working well.
“Each truck takes just a few minutes to unload and more than 2,400 tonnes of concrete will be poured into the foundations today.