Professor Alain Holeyman is still active in pile driving research. The latest involvement of the laboratory concerns tests for Mustafa Jafari’s research on “Numerical and experimental investigation of monopile driving resistance in carbonate rocks”. For this purpose, the FONDEOLE driving system is used in order to install model pipe piles in carbonate rocks. This original system was developed in 2015 thanks to the financial support of Walloon region. It can capture short impact events (about 2 Milliseconds). The driving resistance is calculated from the strain and acceleration records along the pile. A laser sensor tracks pipe displacement during impacts.
Major elements of the system are:
1) A two-segment steel pipe stabilized with lateral supports/seating system: a 4m-segment at the top guides strain wave generated during impact in order to install another 1m-segment at the bottom. The two pipes are assembled by a sleeve. The system allows for two different model pipe diameters: 60mm and 110mm.
2) The Loading system consists of (1) Ram mass, (2) Load frame (rope, pulley and guiding rods) and (3) cushion. Maximum drop height is about 1m. Ram mass can be increased up to 20 kg.
3) The specimen is placed at the bottom of the pipe. The 1m-segment of the pipe penetrates the specimen.
4) The instrumentation consists of standard foil strain gauges, piezoelectric accelerometers, and a laser displacement sensor. It is worth mentioning that the instrumentation system of FONDEOLE can be adapted so that Pile Driving Analyzer (PDA)™ tests can be performed.
5) An old National Instruments SCXI chassis house is use for power, and control signals conditioning modules combining whit a DAQ- acquisition card and a user interface Aquimem-Mx developed in LABVIEW at LEMSC.