Evolution Prediction Of Erosion And Deposition In The East Coast Of Laizhou Bay After The Implemention Of The Coastal Planning

Laizhou bay has four of the nine concentrate and intensive sea application area inthe core zone of the Blue Economic zone of Shandong Peninsula.Among the acreageof sea filled of the first-stage project which is located in the east coast of Laizhou bayof the Ocean Equipment Manufacturing Industry of Longkou bay is nearly50sq.km.The scale of encircling the sea to make land is so large that undoubtedly thestatus of the tide,wave, erosion of the Laizhou bay will be influenced,and thenErosion and Siltation and the changing of shoreline of the sea area of the east coastand nearby area of Laizhou bay will be influenced. The research of Erosion andSiltation of nearshore sea area of east coast is significant of guiding the area selectionof the coastal engineering of this area and the development of the economy of coastalregion.This article based on the subtask of the ecosystem’s research of regionaldevelopment and intensive sea application surround the Bohai sea,which is calledthe technical research of the evaluating of the influence of the intensive seaapplication on the resource.This paper use the erosion law and protectprogramming of the Zhaoyuan Coastal Section and the written report of the overallprograming of sea application of region development of the intensive area of high-endmanufacturing industry in port-vicinity area of Longhai Bay as the first group of data.And it applies the methods of merical simulation and empirical formula,study on thelaw of evolution of Erosion and Siltation of the nearshore sea area of easten coast ofLaizhou bay after the large scale of encircling the sea to make land.This text exploit the method of standard harmonic analysis to analyse thecharacteristic of tide and wave in the sea area of the research zone;use the method of grading analysis to analyse the characteristic of compose and distribution of thesediment in the surface layer of the research zone;use hydrodynamic force moduleand the sediment transport module of the Mike21model to simulate and analyse thecharacteristic tide field wave field and Erosion and Siltation of sea floor and then getthe Erosion and Siltation tend of the research area;use empirical formula to couplingthe tide and wave,and figue out the maximum erosion deepness under extremecondition,and analyse the evolution law of Erosion and Siltation of the researchingarea after encircling the sea to make land;use balance kenel experience model of planeof bay between the cape and LITLINE to verify the conclusion gained.There are sandy silt， silty sand,fine sand,medium sand,coase sand,gravelsand,sandy gavel and gavel in the sediment in the surface layer of the researcharea..And the sand taper off from the shore to the sea,and the separation is bad,andmiddle part and easten part is coarse and the westen part is fine.Frequency curve ofsample fall into unimodal,doublet and transition state between the two.Through numerical simulation, the velocity of current is fundamentallyinvariant;The velocity of current in Longkou bay decreases4～8cm/s with theinfluence of the engineering.The velocity of current of the nearshore area of theZhaoyuan part to Shihu chew of the sea encircling project decrease by4～12cm/s.Inthe half round zone which the engineering forms,the velocity of current changes mostobviously to24cm/s; The the velocity of current increases by0～8cm/s in thedirection of SW of sea encircling project.The velocity of current of the channelbetween the sea encircling project area and the shore and the channel between the twoincreases by4cm/s.Contrast with the status before and after the sea encircling project,it is found thatafter the sea encircling programming is carried out,the strength of eroding in theresearching area decreased. The eroding effect of Qimu island weakens.Because thecape of the Qimu island is the basement exposure area,the eroding depth hardlychanges.The erosion depth in the south part of Qimu Island decreases by2～4mm.Longkou bay hardly changes before and after Erosion and Siltation.The Longkou section of sea encircling project, which is influenced by ski-jump floweffect of the front end of the project,has its westen part increased by0～4mm.Theerosion depth of the westen part of the Zhaoyuan section of the sea encircling projectincreases by0～2mm.The direct route erosion strength between the project increases，while the erosion strength in the channel between the project and the channeldecreases. In the sea area between the mouth of boundary river and the Shihuchew,the erosion strength changes little compare with the condition before seaencircling except for the mouth of boundary river.Headland bay equilibrium-based empirical model and LITLINE show that afterthe implementation of the implmentation of the coastal planning for one year, the eastside of the fishing port forwards102m to the sea, the west side of the reclamationshoreline siltation forward168m, the fishing harbor west side of the shoreline siltationforward430m, the fishing port to the stone tiger shoreline advances to the sea1～3mevery year, to a state of equilibrium.The shoreline between the fishing port and thestone tiger will promote about190～410m to the sea.The Zhaoyuan Coast will besiltation To erosion and deposition trends and numerical simulation of the empiricalformula to calculate the maximum scour depth conclusions.