Measuring wave impact induced pressures with a pressure mapping system

Abstract

The use of a pressuremapping system formeasuring wave impact induced pressures is evaluated in this paper. A set-up and a calibrationmethodology are suggested and employed for thiswork. The system is validated against pressure transducer and load cell measurements and for a range of waves breaking on a vertical seawall. For a large number (120 measurements for each case considered) of breaking and broken waves interacting with the wall, the peak pressure (Ppeak) profiles and the pressure distribution maps reported by the system agree wellwith results acquired using pressure transducers. Although the pressuremapping system tends to underestimate Ppeak, differences on themean of the 3, 5 and 10 highest Ppeak rangewithin±10%, while for themajority of the measurements the error on the integral of the acting pressures (the acting force compared with the force measured by the load cell) ranges within ±20%. It is concluded, that through careful calibration and set-up the pressure mapping system has the capacity to provide pressure distribution maps with a good accuracy. It is not, however, considered to constitute the absolute alternative to pressure transducers and thus a combined use is suggested for applications where a very high level of accuracy is required.