• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.140-141
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• 2005

This study describes the postinstallation maintenance technology of artificial reefs and their improvement. The maintenance technology of artificial reefs consists of four steps; the investigation of volumes of installed reefs, the removal of fishing gears entangled in reefs, the estimation of reef functions, and the establishment of surveyed results in the data base. The proper understandings of their steps is the key to improve the maintenance technology of artificial reefs.

• Advances in concrete construction
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• v.12 no.5
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• pp.411-418
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• 2021

Roller compacted concrete (RCC) used in the island reef airport runway will be subjected to the coupling actions of the fatigue impacts and the salt spray cycles, which will accelerate the deterioration of runway concrete and even threaten the flight safety. A cyclic impact testing machine and a climatic chamber were used to simulate the low-velocity fatigue impact and the salt spray cycles, respectively. The physical properties, the microstructures and the porosity of RCC were investigated. The results show the flexural strength firstly increases and then decreases with the increase of the fatigue impacts and the salt spray cycles. However, the decrease in the flexural strength is significantly earlier than the compressive strength of RCC only subjected to the salt spray cycles. The chlorine, sulfur and magnesium elements significantly increase in the pores of RCC subjected to 30000 fatigue impacts and 300 salt spray cycles, which causes the decrease in the porosity of RCC. The coupling effects of the fatigue impacts and the salt spray cycles in the later period accelerates the deterioration of RCC.