Dieseko successfully tested a series of vibroflots when densifying granular soil in Dubai at a temperature of +45oC approximately.

In close co-operation with its client in Dubai, Dieseko conducted a number of tests in order to analyse the performance levels of its vibroflots in extreme circum?stances. Vibroflots are commonly used for vibro compaction, a deep compaction technique for densifying granular soils, as well as for realising stone columns.

Dieseko engineer Girt Clazing exp?lains, "With vibro compaction, water under high pressure is jetted sideways and downwards from the vibroflot to assist with penetration. As the designed depth is reached, the ground water is reduced or switched off. When vibrating with an operating pressure up to 250 bar, loose particles are re-packed into a denser state and the lateral confining pressure within the soil mass is increased. The vibroflot is incrementally raised as sand is put to the annular gap around the vibroflot. This process repeats at designated locations at the building site in order to realise the required compaction."

The test configuration involved vibroflots V180 in combination with ICE 600 power packs. The parameters were extreme: realise an 800 mm diameter column at a temperature of 45?C. During the non-stop 30 minute operating time, the completely hydraulic assembly remained well under 60?C!

Clazing says, "In advance, a survey on soil condition was conducted, as a reference. With the monitoring system of the vibroflot, the operator can exactly control the process: start, finish and overall time, depth of penetration, operating pressure. By interpreting the recorded data of the different test drillings, together with the soil survey, we got the most optimised configuration to do the job efficiently."

Vibro compaction with a vibroflot is possible up to depths of more than 60 m. A vibroflot is normally suspended from a standard crawler crane. Real-time data from a single or tandem setup is displayed on the monitor and can be downloaded at any time to support service intervals and job reports.

The Dieseko Group is specialised in the engineering, production, rental and sales of vibratory hammers (variable moment, high frequency), ring and linear vibratory hammers, pressing machines, power packs (200-5,000 kW), vibroflots and clamp systems. Within the holding, PVE and ICE are specialised in hydraulic vibratory hammers. In total, the Dieseko Group employs 150 people.