Harbor Structures

Harbor structures are very accessible and can be investigated without the effects of wave motion. Grounding of steel pilings presents no problems and the work can be carried out from the quay (see the left-hand side of Fig. 16-13). With steel-reinforced concrete structures, measurements have to be made from a boat if no reliable contact has been provided in their construction (see the right-hand side of Fig. 16-13). 

In protection with impressed current installations, it depends on the conductivity of the harbor water whether oif potentials can be measured and also whether the IR component can be taken into account. Only very few inland harbors require such expenditure usually the conductivity is sufficiently high. 

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Table 16-4 Cathodic protection systems for coastal and harbor structures...

Marine Structures and Offshore Pipelines 387 16.7.2 Harbor Structures... 

These chemical-shift perturbations harbor structural information. All of the significant changes in chemical shifts of the protein affect those residues located... 

The Navy consists of several components, including ships, submarines, aircraft weapons, and facilities such as buildings, piers, docks, and harbor structures. An internal Navy study conducted in 1993 estimated the total cost of corrosion for all naval systems at 2 billion per year (Sedriks, Office of Naval Research, Personal Communication, July 2000). 

Damage to harbor structures included tilting of caissons supported at 20 ft and tilting of sheet-pile walls due to loss of anchor resistance. Quay walls moved out nearly 2 ft over a distance of nearly 1000 ft. Traces of sand volcanoes found... 

Hayashi, S., Kubo, K., and Nakase, A. 1966. Damage to harbor structures by the Niigata earthquake. 

In order to investigate the protective effectiveness of a silane-based hydrophobic agent used as admixture to the fresh concrete, an experimental program was carried out, some results of which are briefly reported in the following. For comparison, some field investigations on the effectiveness of a traditional surface hydrophobation of two concrete harbor structures based on similar hydrophobic products are also briefly reported. 

From the field investigation of both a new and old concrete harbor structure which had been proteceted by a surface hydrophobation, a good protective effect of the surface treament was observed. 

For both concrete harbor structures, the hydrophobic agents had only formed a thin layer of the hydrophobic agents on the concrete surface due to high moisture contents in the concrete substrate. Thus, it was difficult to detect any difference in protective effectiveness both between the two different hydrophobic agents applied and also between one layer (0.25 mm) and two layers (0.5 mm) of application, respectively. 

For the surface treatment of the old concrete harbor structure, the chloride front had already reached a depth of up to 30-40 mm, so the surface treatment was primarily carried out in order to retard the further chloride penetration. In this structure, a redistribution of the chloride content was observed with a reduced chloride content in the surface layer and a further penetration of the chloride front deeper in. For such a surface protection to be effective, therefore, the depth of chloride penetration at the time of surface treatment should not be too deep. 

The authors would like to acknowledge the financial support received from Sto Norge AS and also for the valuable assistance of H. Chr. Flor during the field work. For one of the concrete harbor structures investigated, the authors would also like to acknowledge the assistance received from the Trondheim Harbor Authorities. 

V. Arskog, M. Ferreira and O.E. Gjorv Durability and Performance of Norwegian Concrete Harbor Structures, Vol. 1, Proceedings. Fourth International Conference on Concrete Under Severe Conditions - Environment and Loading, edited by B.H. Oh, K. Sakai, O.E. Gjorv and N. Banthia, Seoul National University and Korea Concrete Institute, Seoul (2004) pp. 

The agitation conditions along the passage have been calculated by means of a modified mild slope linear wave propagation model. Wave reflection from bathymetry (up to second order in bed slope) and coastal or harbor structures is... 

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