Study On Stability Of Whalf Low Pile Cap Retaining Wall In Landslide Area

After the navigation-power junction of the mountainous rivers was built and theimpoundment was finished, the water level rise would bring some problems about bankstabilizations inevitably. Due to the improve of channel conditions in reservoir areasand the urgent demand of water transportation at the same time, the better port coastalresources are getting less and less, and some wharfs have to be built in the places withpoor geological conditions even the geological hazards. Building wharf structures onthe shore lines with problems of high and steep topographic areas, deep cover layersand the slippery stratums, people should guarantee the stability of wharf structures andslippery stratums at the same time and make them the integrated design. Combiningwith the engineering example of wharf in the hub of the reservoir of Jia ling river chostreet, the paper took the method of finite limit analysis to research the stability ofretaining walls of low pile cap in wharfs, analyse the stability and its influencingfactors of wharf structures on slippery stratums and put forward to the calculationmethods of stability and the optimization schemes adapt to the low pile capsystematacially. Specifically, the main research work and achievements of this paperinclude the following aspects:①Applied the PLAXIS finite element software, used the limit analysis method tocalculate the slope stability and compared with the calculated results with the limitequilibrium method, Which proved that the finite element limit analysis method can beapplied to the stability analysis of wharf bank slopes. The low pile cap retaining wallcan greatly enhance the stability of the bank slope. Comparing with the weighing typeretaining wall structure, the slope stability performances with the low pile cap retainingwall meet the requirements but it is much cheaper.②Based on the Coulomb active earth pressure calculation theory and the landslidethrust calculation theory, the paper discussed three earth pressure calculation methodsof low pile cap retaining wall,which are the methods the earth pressure calculation ofoverall structures, the earth pressure calculation of Sub-bearing on or under stage andthe earth pressure calculation of the finite element method, showing that the result s ofSub-bearing on or under stage and the finite element method were close and they can berecommended in practice. ③Used the single factor sensitivity analysis method to analyse the sensitivedegrees of water levels, stacks, mooring forces, rock-socketed depths and filling’sshear strength on the whole stability of wharfs in quantitative. Mooring forces, waterlevels, the rock-socketed depths have smaller influence on stability of low pile capretaining wall pier, but filling’s shear strength and wharf loads have greater influenceon the overall stability. In practice, the chosen type of fillings of retaining walls andthe control of stacks in use should be concerned.④Used the finite element method to calculate the soil pressure on low pile capretaining wall and used the finite element software MIDAS to calculate the pile’sinternal forces and stresses of low pile cap. Through comparative analyses of internalforces and costs, the conclusion comes that the optimal structural size of low pile capretaining wall is that wall height8m, center distance of pile foundation5m, centerrow distance of pile foundation5m.