Field Testing

Full scale lateral loading trials

In order to verify the performance of Waterloc, in terms of lateral loading resistance, a series of full scale field trials have been undertaken.

To simulate worst case conditions a column of seven Waterloc cells (4 metres from ground level to the underside of the lowest cell) were installed within an excavation which was 600mm wider than the cells. The excavation was profiled at an angle of 30 degrees away from the cells to ensure that the full loading effect of imported material was applied to the structure (Figure 1). The excavation was then backfilled in layers with imported 10mm rounded granular material (angle of repose approx 30 degrees) up to the level of the top cell (Figure 2).

Measuring equipment, pre-fitted to each cell, was then used to monitor the lateral deflection at the mid point of the vertical face of each Waterloc unit. From this test work, it was concluded that, under worst case conditions, the horizontal deflection in Waterloc HD cells is less than 10mm at an installed depth of 4 metres and less than 10mm for a standard Waterloc cell at a depth of 2 metres.

The trial installation was then monitored over an extended period to verify that equilibrium had been achieved. No further significant deflection occurred.