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Marine clay is a type of clay found in coastal regions around the world. In the northern, deglaciated regions, it can sometimes be quick clay, which is notorious for being involved in landslides. Clay particles can self-assemble into various configurations, each with totally different properties. When clay is deposited in the ocean, the presence of excess ions in seawater causes a loose, open structure of the clay particles to form, a process known as flocculation. Once stranded and dried by ancient changing ocean levels, this open framework means that such clay is open to water infiltration. Construction in marine clays thus presents a geotechnical engineering challenge. 〔("Overcoming Problems with Marine Clays", Fairfax County, Virginia )〕 Where clay overlies peat, a lateral movement of the coastline is indicated and shows a rise in relative sea level Swelling of marine clay has the potential to destroy building foundations in only a few years. Due to the changes in climatic conditions on the construction site, the pavement constructed on the marine clay (as subgrade) will have less durability and requires lot of maintenance cost. Some simple precautions, however, can reduce the hazard significantly . During the construction of Marina Barrage in Singapore, marine clay was found at the site. Since marine clay was the cause of the Nicoll Highway collapse years previous, the construction team removed all the marine clay to ensure the stability of Marina Barrage. Later on, they found marine clay mixed with seawater even in the deeper underground. Geotechnical problems posed by marine clay can be handled by various ground improvement techniques. Marine clay can be densified by mixing it with cement or similar binding material in specific proportions. Marine clay can be stabilised using wastes of various industries like porcelain industry and tree-cutting industries. This method is usually adopted in highways where marine clay is used as a subgrade soil. ==References== 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Marine clay」の詳細全文を読む スポンサード リンク
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