About Ocean Engineering
Ocean engineering refers to a new comprehensive technological science formed by the application of marine basic sciences and related technical disciplines in the development and utilization of the ocean, and also refers to the development and utilization of various buildings or other engineering facilities and technical measures.
The marine development technology and equipment presented by the development of marine engineering and science and technology in the world are constantly improving, and promoting the comprehensive development and utilization of marine resources. The development and utilization of marine energy has become an important pillar of the development of various marine countries, and the development of marine biological resources has always been a hot spot for competition among countries in the world , Marine pollution control and prevention have also received great attention from the international community. Marine and land-related engineering and technology are playing an increasingly important role in modern marine development.
The contents of marine development and utilization mainly include: marine resource development (biological resources, mineral resources, seawater resources, etc.), marine space utilization (utilization of coastal beaches, marine transportation, offshore airports, offshore factories, undersea tunnels, undersea military bases, etc.), ocean Can be used (tidal power generation, wave power generation, thermoelectric power generation, etc.), coastal protection, ocean construction and survey, etc. The term "ocean engineering" was first proposed in the 1960s, and its content has been gradually developed and enriched with the exploitation of offshore oil, natural gas and other minerals in the past two to thirty years. According to the sea areas developed and utilized by the ocean, ocean engineering can be divided into coastal engineering, offshore engineering and deep-sea engineering, but the three overlap.
Offshore engineering begins with coastal engineering serving the development of coastal zones. The countries along the Mediterranean Sea began to sail and build ports in 1000 BC; China built ports along the coast as early as 306-200 BC, and built coastal protection projects along the southeast coast in the Eastern Han Dynasty (25-220 AD); the Netherlands At the beginning of the Middle Ages, the sea was also built, and the sea was reclaimed and landed with the sea. For a long time, with the development of navigation and the growth of production and construction needs, coastal engineering has been greatly developed, and its contents mainly include coastal protection engineering, sea reclamation engineering, harbor engineering, estuary management engineering, marine dredging engineering, coastal fishery Engineering, environmental protection engineering, etc. However, the term "coastal engineering" did not appear for the first time until the 1950s. With the formation and development of marine engineering hydrology, coastal dynamics, coastal dynamics and geomorphology, and other related disciplines, coastal engineering has gradually formed a systematic Technical subjects.
Since the second half of the 20th century, the world’s population and economy have expanded rapidly, and the demand for protein and energy has also increased sharply. With the exploitation of oil and natural gas in the continental shelf waters, as well as the expansion of marine resource development and space utilization, the scale has been adapted The offshore project has become one of the fastest growing projects in the past 30 years. The main sign is the emergence of offshore platforms for drilling and exploitation of oil (gas), and the scope of operations has expanded from coastal waters within 10 meters of water to continental shelf waters at a depth of 300 meters. Seabed mining has developed from shallow coastal waters to deeper seas. It is now possible to drill in seas with a depth of more than 1,000 meters for oil extraction, drill in the oceans with a depth of more than 6,000 meters, and collect manganese nodules at a depth of 4,000 meters. Marine diving technology has also developed rapidly, and saturation diving has been possible, and the diving depth can reach more than 10,000 meters when loaded into the submersible. Marine robots for diving operations have also appeared. In this way, the offshore engineering (or offshore engineering) of the continental shelf waters and the deep-sea engineering of the deep waters have far exceeded the scope of coastal engineering, and the basic science and engineering technology applied are also beyond the scope of traditional coastal engineering, thus forming A new type of marine engineering.
There are many structural types in marine engineering, and the commonly used ones are gravity buildings, air-permeable buildings and floating structures. Gravity buildings are suitable for coastal zones and shallow coastal waters, such as sea lifts, revetments, piers, breakwaters, artificial islands, etc., built with soil, stone, concrete and other materials into a slope, vertical wall or mixed structure. Permeable buildings are suitable for shallow seas with soft soil foundations, and can also be used for deep waters, such as high-piled wharves, island wharves, shallow sea offshore platforms, etc. Among them, the offshore platform is built with steel, reinforced concrete, etc., which can be fixed or movable. Floating structures are mainly suitable for the continental shelf waters with large water depths, such as drilling ships, floating boat platforms, semi-submersible platforms, etc., and can be used as oil and gas exploration and deep mining platforms, floating oil storage tanks and oil refineries, floating power stations , Floating airport, floating sea water desalination device, etc. In addition to the above three types, unmanned deep submersibles have also been developed in the past 10 years, which are used in production systems for remote seabed mining.
The marine environment is complex and changeable, and marine engineering often has to withstand the strong effects of typhoons (hurricanes), waves, tides, ocean currents, ice, etc. In shallow waters, it is also affected by complex topography, beach evolution, and sediment transport. Marine environmental factors such as temperature, earthquakes, radiation, electromagnetics, corrosion, and biological attachment also have an impact on certain marine projects. Therefore, when analyzing the external force of buildings and structures, consider the random characteristics of various dynamic factors, consider dynamic issues in structural calculations, consider periodic loads and soil uncertainties in foundation design, and consider material selection Economical and durable etc. are all very necessary. Ocean engineering is costly and the consequences of accidents are serious. Strict demonstration and inspection of its safety is essential.
The development of marine resource development and space utilization, as well as the construction of a large number of engineering facilities, will bring various impacts to the marine environment, such as beach evolution, water pollution, and deterioration of ecological balance. Sufficient attention must be given. In addition to conducting forecast analysis and research and strengthening on-site monitoring, various preventive and improvement measures must be taken.