Dynamic Pile Testing

The dynamic loading test method allows a large number of piles to be tested in record time and at an extraordinarily low cost, which greatly improves the reliability of the data, unlike static tests alone.

The dynamic pile loading test was developed in the 1960s in North America. Its use is spreading in the Nordic countries, Japan and Latin America. Its very economic nature also attracts emerging countries that adopt it massively, sometimes at the price of the rigor of execution and analysis, and therefore the reliability and accuracy of the results.

Today, most international building codes encourage the use of dynamic loading tests. Several thousand are executed worldwide each year, including less than a dozen in France.

Eurocode 7 allows for a significant reduction in design basis safety coefficients, if these are controlled by dynamic load tests, together with a static test for each type of soil and pile.

The load bearing capacity as measured by a dynamic loading test is in good agreement with the static tests. The observed differences, generally less than 15%, are mainly due to the healing time of the soil and the choice of failure criteria.

Services

Service Philosophy

Originally from the offshore Oil&Gas Industry, we believe that the value of our offshore construction services is a result of:

Reliability of the service
Quality of the collected data, for an appropriate analysis
The sound understanding of theoretical phenomenon involved, together with G-Octopus’ vast experience in foundation design and installation, and pile acceptance.
A focus on zero barge time loss during work preparation as well as and execution phases.

The recognition of G-Octopus as a market leader for the reliability of its service, the accuracy of its analysis and the quality of the data, can be attributed to our key values:

Personnel are thoroughly selected based on technical skills and personality and provided with training on theoretical and practical issues related to Pile Driving Monitoring. Key project personnel are certified PDA signatories at an advanced level.
Only the latest versions of the software are proposed (older versions as back-up), from the world leading Pile Driving Monitoring equipment manufacturer Pile Dynamics, Inc. (PDI).

Advanced Interpretation and Analysis

We can provide advanced interpretation of the pile driving monitoring data. Utilising years of experience, we are able to provide the following services:

Signal matching analysis utilising CAPWAP – a software program that calculates total bearing capacity of a pile as well as resistance distribution along the shaft and at the toe.
Assessment of in-situ pile capacity in case of premature pile refusal
Pile fatigue assessment
Calibration of the hammer/pile/soil numerical model for site specific driving predictions
Construction of a numerical based soil model calibrated through analysis of instrumented pile tests which permits the calculation of pile capacity for none instrumented piles. (A method approved by Eurocode 7)
Definition of pile driving criteria for pile tip integrity while driving, in soft rock for instrumented piles and non-instrumented piles.

Equipment

We operate the Pile Driving Analyser PDA8G acquisition units manufactured by PDI, which are widely regarded as the most reliable systems on the market. The PDA acquisition units are deployed in conjunction with PDI manufactured strain gages and accelerometers, and the data captured is analysed using the latest versions of GRL WEAP, PDA-S and CAPWAP. Our equipment capabilities include both above-water and under-water pile driving, all of which can be deployed at short notice.

Operations

We can provide fast assistance to the Contractor on all piling issues, and the on-site analysis of data enables a preliminary assessment of the hammer/pile/soil system to be given virtually in real time.

Our engineers are familiar with the offshore environment and trained to liaise with barge masters and deck foreman to minimise interference with the installation schedule.

Our equipment is thoroughly checked before the operations, and mobilised with 100% redundancy. Pile Driving Monitoring generally results in zero barge time loss.