The Research Of Vacuum Preloading In Shallow Foundation Treatment

Vacuum preloading is a kind of foundation treatment which developed in a decade,it has many advantages to improving the soft soil foundation, along with constructionupsurge, the method get further extensively applied, at the same time there are somedevelopments of improvement principle,constructiont echniques and design theory.The Tianjin harbor, a big harbor in northern area, is developing in a unprecedentedway. Because of the largescaleconstruction developing, foundation treatments mustto be adapted currently rigorous situation, for example urgent time, as the soil needingfor treatment is silt,si lt quality soil even slurry etc. which called verysoftsoil causingthe phenomenon of transporting sand, soil material of difficultly and great price, andthe large machine can't enter an etc.Based on the former researchers' work, combing with the actual soil circumstancein Tianjin harbor research vacuum preloading in application of shallow foundationtreatment, we try to improve flabbily blowing soil into engineering soil as soon aspossible, so this text mainly works as follow:(1)This text analyzes the degree of consolidation,settlement,method ofcalculating bearing capacity of foundation soil? contrasts the time factor and degree ofconsolidation in different depths? analyzes settlement by the thought of layerwisesummation method and compares it in calculating with spot experiment? Vacuumpreloading in shallow foundation treatment can form double layers foundation withtop layer hard and down layer soft, discusses bearing capacity of foundation soilunder under the sistuation that have a hard shell layer.(2)Combining the spot experiments data, the text compares the changing of thephysical and mechanical property in before consolidation with after consolidation, thesame time analyzes the changing process of layer settlement,delaminationsettlement,pore water pressure and side toward movement in monitoring.(3)Im proving construction technique according to the soil property of the harborand practical nervous circumstance of sand,soil.