The Influence Of The Construction Of Road Into The Sea In Dagang Oilfield On The Erosion And Sedimentation Of Coast Shoal Of Port Of HUANGHUA

With abundant oil reserves in the study area, when the oil and gas resources inthe beach was exploited, Zhangdong seawall, Zhuanghai2×1road into the sea andZhuanghai4×1road into the sea were built along the intertidal zone systematically inthe Dagang oil field, which changed the dynamic environment of the beach andbrought some influence on the scouring and sediment development of the beachtopography in the study area. Predecessor measure current, water depth and section,through the sediment dating method to estimate the rate of sediment silt, but lack ofmathematical model, just preliminary assessment into the influence of the evolution oferosion and deposition of the road into the sea. Based on the collection on the basisof predecessors’ data, I have done the tide harmonic analysis, sediment characteristicsand sediment transport trend analysis. The changes of erosion and deposition isanalyzed before and after the roads into the sea (Zhangdong seawall, Zhuanghai2×1road into the sea, Zhuanghai4×1road into the sea) are built are built by the ECOMmodel and the sediment deposition numerical modeling. The results have beenverified by sediment dating methods. by estimating the transport rate along the coast,Satellite remote sensing image verify and analyze of the influence of erosion anddeposition along into the sea.Simulating flow field characteristics in the study area by the ECOM model, it geta validation of the measured current and tidal data. The results is consistent.Oceancurrents are mainly trend in the study area,it is regular semidiurnal tidal current model.The trend has two characteristics of rotating and reciprocating. The direction offlood current mainstream is WSW to W, flow velocity from30cm/s to65cm/s. Thedirection of ebb current is ENE to E, velocity from30cm/s to60cm/s. After theconstruction of the road into the sea. The direction of northern of the road into thesea is counterclockwise deflection, and the southern is clockwise deflection. Flowvelocity decrease on both sides of the road to the sea, increase in the southeastern inthe high water time and maximum velocity of ebb tide time. The terminal of theroad to the sae velocity increase and on both sides of the flow velocity decreases onan hour before high water time. The northern flow velocity of Zhuanghai4×1road into the sea decrease and the southern increase.The changes of erosion and deposition is analyzed before and after the roads intothe sea are built by sediment deposition numerical modeling. The result show that itis obvious the deposition by the bank between Nanpai river and Xujiabao before theroads are built. Annual sedimentation is0.170～0.210cm. The deposition rate israpidly between the three Nanpai river, Zhuanghai2×1road into the sea andZhuanghai4×1road into the sea after the roads are built.Annual sedimentation isbigger than0.210cm. It is eroded the north sea coast of Zhangdong seawall, thesouth and southeast coast of Zhuanghai4×1road into the sea. The change of otherregion is very small. Net annual sediment along the bank is2×104m3, the direction tothe south. The sand sources is deficient and the deposition velocity is low in the area.The erosion and deposition of sand is affected by local ocean current dynamic. Theresults have been verified by sediment dating methods and satellite images. Thispaper established two numerical simulation are suitable for this area.The effect to the sediment distribution on the coastline from the road into the seais very weak. Human activitythe is the main force for the coastline. Seashoreserosion and deposition of sediment has certain influence after the construction of theroad, limited to the nearby beach, changed very little. It is not changed far fromengineering area.