Research On Characteristics Of Coastal Sediments Around Huanghua Port And Construction Measurements Of Reducing Sedimentation

As an important port which transports coal from west to east in China, HuanghuaPort has been puzzled by the severe siltation of outer channel since being built in 2001.Accompanying with the goal of becoming one of the bigest harbors whose throughoutamounts to one hundred millions tons in 2007 and the recent construction of thesecond railway line from Shanxi to Huanghua, it is a pressure how to maintain theouter channel's navigable depth. Since the 1980's, many scientific researchinstitutions, construction companies, colleges have been engaged into the study of thesedimentation of Huanghua port and have accumulated a large amount of survey data.On the basis of the historic data and research achievements, the coastal properties, thebasic hydraulic characteristics and the transport properties of sediment are studied inthis thesis. The reasons of sudden siltation in the outer channel of Huanghua Port areanalyzed. The main conclusions are as follows: The coast around Huanghua Port should be named as silty or silt-muddy coast. Ithas been in morphological process by long-time erosion-retrogression and destructionfrom the ancient Huanghe Estury's abandonment. The sudden siltation in the outerchannel of Huanghua Port is mainly caused by large wind waves. The characteristicsof sedimentation is that the sediment is suspended by waves and transported bycurrents. The main source of the sedimentation is the sediment on the bed surfacelayer in the shallow water around the Huanghua Port, which is initiated, thansportedand silted due to waves and currents. The sediment around Huanghua Port is mainlytransported near sea bed. The reasonable way to explain that the siltation of the outerchannel during a storm process amounts to several millions cube meters is the conceptof "high concentration layer near sea bottom". After analyzing the reasons of sudden siltation, the model of calculating thesedimentation volume and the rules of regulation works are presented. The benefits ofthe regulation works in reducing siltation are demonstrated, which provides the basisfor the implementation of regulation works. Based on the recent field measurementsafter the extension of breakwaters, it is shown that the regulation works has takeneffect on decreasing sedimentation. It is proved that the analysis and the calculatingmodel presented in the thesis are reasonable.