Determination of the static pressure loads on a marine composite panel from strain measurements utilising artificial neural networks

Abstract

One of the first steps in marine structural design is to calculate the wave-induced loads and load combinations. In contrast with both the hydrostatic loads and the self-weight loads which can be evaluated with a high degree of confidence, it is more difficult to measure the in-service hydrodynamic loads generated by sea waves. Direct pressure load measurement techniques can currently provide only data at finite locations while classical analytical techniques require knowledge of all the parameters that influence the load and that each parameter is studied independently. Therefore, a novel technique is required to overcome these limitations by providing a method of measuring the pressure load over large areas with relatively few sensors and minimal data collection. This paper reports research undertaken to develop an inverse problem approach utilising an artificial neural network for measurement of the pressure loads experienced by marine structures. The suitability and performance of utilising an artificial neural network for quantifying the pressure load applied to a marine structure is presented. It was found that the artificial neural network was able to estimate accurately the pressure loads applied to up to 12 locations on the structure. It is concluded that the inverse problem approach can be used to estimate the applied loads on the marine structure in real time from strain measurements.

In-Service Transient Load Measurement on a Large Composite Panel

“…Inverse problem analysis is based on accurately calculating the external loads or boundary conditions that generate a known amount of strain at predetermined locations on a structure. An ANN, as an inverse problem solver, can be utilised to determine a relationship between the cause and its effect [28]. In this study, the impact loads (the cause/output) on a composite panel are quantified by acquiring repeatable peak strain responses (the effect/input) to these loads from the panel.…”

“…A novel approach for the determination of pressure loads experienced by marine structures is the utilisation of Artificial Neural Networks (ANN) [28]. ANN methods are utilised in research areas where problems are solved by pattern recognition, generalisation and pattern classification [29].…”

“…In a recent study by the authors [28], it is shown that the inverse problem approach can be used to estimate the loads applied on a marine composite panel from the strain measurements when behaving linearly. A comparison of the ANN loads with the actual applied loads indicated a very good performance of the methodology.…”

Using artificial neural networks and strain gauges for the determination of static loads on a thin square fully-constrained composite marine panel subjected to a large central displacement

“…An ANN, as an inverse problem solver, can be utilised to determine a relationship between the cause and its effect [20] . In this study, the static loads (the cause/ output) on a composite panel are quantified by acquiring repeatable strain responses (the effect/input) to these loads from the panel.…”

“…Additionally, the approach avoids the need to have information on the component geometry and material properties [18,19] . Ramazani et al [20] have recently shown that the inverse problem approach can be used to estimate low loads applied on a composite marine panel from a small deflection and its associated strain measurements. A comparison of the ANN loads with the actual applied loads indicated a very good performance of the methodology.…”