Research Of Accelerated Creep Properties And Microscopic Mechanism On Soft Clay

With the development of Tianjin Binhai New Area, more and more structuresneed to be built on soft clay foundation. Soft clay, with such characteristics as highmoisture content, high compressibility, high void ratio, low permeability and lowintensity, should be, therefore, particularly processed before used as foundation soil.But settlement still occurs under long-term dynamic loading even though the clay ispre-processed，and will be greater under long-term dynamic circulative loading，so itis of high necessity that the creep characteristics and its microscopic mechanism ofsoft clay under dynamic loading should be researched.With soft clay sampled from Tianjin Binhai New Area，tri-axial creep tests underboth static loading and dynamic loading are respectively carried out. In this paper，clay’s creep characteristics under both static loading and dynamic loading, togetherwith the influencing factors, are analyzed from the angle of macro mechanics. Inaddition, the creep of soft clay and microscopic mechanism of accelerated creep arealso analyzed through the contrast of microstructure parameters before and after thetests.The initial creep rate is greater and the creep rate after entering the stable creepstage is smaller if the confining pressure is greater under the static load. The stresswhen the soil sample is damaged is smaller if the load ratio is greater. The transientcreep rate is greater and the time is shorter which is needed when the creep becomesstability if the load increment is greater.Accelerating creep condition, the dynamic load of vibration frequency onmicrostructure parameters has a great influence on the performance of, mainlydisplays in: with the increase of vibration frequency, pore size, particle size, theabundance, complexity and fractal dimension are showed a trend of decrease, whilethe particles of the directional property is increased.