Improvements in prospect for checks on defective foundation piles

Published: 27 March 2014

At Deltares, new monitoring methods are being tested for identifying defects in foundation piles, such as cracks and changes in shape, to reduce failure costs in the construction industry. The focus is on foundation piles that are formed in the ground: the piles are not driven but built up by injecting concrete through screwed piles. This technique is used on construction projects in soft soil in built-up areas, preventing vibration and possible damage to buildings and infrastructure in the vicinity.

There are doubts about the quality of between 5,000 and 10,000 piles a year

Between 40,000 and 50,000 foundation piles of this kind are produced annually. The standard approach to checking them is acoustic ‘tapping’ to see whether the pile conforms with the requirements. This fails to generate adequate information in between 10 to 20% of the measurements. On those occasions, it is impossible to decide whether there are any anomalies weakening the pile. In turn, that leads to construction delays and pushes up costs. To cut those delays and costs, we will be teaming up with a number of other stakeholders over the next four weeks to test five new measurement techniques. We will be trying out a range of techniques that use sound, heat or electricity to build up a ‘picture’ of the concrete in the ground. The new measurement techniques are expected to provide more precise information about whether the foundation pile complies with all requirements. The tests are part of the Geo-impuls research programme, which aims to reduce failure costs by 50%.

De meetapparatuur om de funderingspalen te testen komt in de holle buis.

The monitoring equipment to identify defect in foundation piles will be placed in the tube.