Dynamic Load Testing

Over the past 40 years Dynamic Load Testing has become an accepted method of predicting pile performance, assessing pile integrity and confirming design parameters.

What is Dynamic Load Testing used for?

Dynamic Load Testing involves the measurement of force (F) and velocity (v) at the head of the pile typically after installation by instrumenting the pile with strain gauges and accelerometers.

The hammer impact induces a compressive stress wave which travels down the pile with a constant wave speed (c) and reflects upward traveling compression and tension waves due to changes in pile and soil properties which are measured at the head of the pile.

By striking the pile with a drop hammer, the force and velocity at the pile head can be measured. Using stress wave theory, the measurements are analysed to predict the pile bearing capacity. Further computer analysis using CAPWAP software yields a variety of pile performance data including shaft resistance distribution, toe bearing and static load v deflection data.

What are the advantages of Dynamic Load testing?

  • Many tests can be undertaken across the site within one day so the variation of pile settlement across the site can be assessed along with the potential for differential settlement.
  • This test method is an economic alternative or supplementary test to the traditional static load test and can be applied to all pile types, typically precast piles.