Influence of site geology on wear problems
The dredging works in the Middle East and Gulf areas had given the contractors a feel for rock dredging and considerable experience was built up, which was used to evaluate tenders for new projects. Contractors could see a relationship between dredgeability and rock strength and also correlations of wear with rock strength were found. In 1985 a dredging project was carried out at Port Hedland, Western Australia, which aroused concern. Extremely high wear rates were experienced, which were unexpected by the contractor involved. The site investigation done by the consultant geotechnical engineer can be considered as typical for a dredging project. The attention was focused on the dredging site itself and emphasis was put on the gathering of geotechnical information. The geotechnical model was also based on an interpretation of the local geology. The regional geology was described by concentrating on the coastal area itself.