Experimental Research On Fluidity And Strength Behavior Of Solidified Clays Under Seawater Environment

At present, many scholars have carried out the experimental research on the fluidity and strength behavior of solidified clays,but the experimental studies on the flow performance of solidified clays under seawater environment are still lacked.At the same time, the unconfined compression tests and mechanism analysis of solidified clays with different sodium chloride concentrations are still not perfect.Therefore, it is necessary to carry out experimental research on the fluidity and strength properties of solidified clays under seawater environment.In this paper, three kinds of common clay minerals were measured for liquid and plastic limits, clay content, fluidity and strength indexes and two kinds of natural clays were also tested for liquid and plastic limits, fluidity and strength indexes.On this basis, the rules of fluidity, viscous parameters and strength indexes of solidified clays were analyzed with the change of salinity,and the mechanism analysis of sodium chloride concentrations effect on the fluidity and strength behavior was discussed. The main research contents are as follows:1.Experimental research on the basic characteristics of clay minerals and the fluidity and strength behavior of solidified clay minerals under different salinities. Three kinds of common clay minerals were choiced as the research object,the proper soaking time was determined,then immersion replacement method was adopted to prepare the specimens under different salinities,densimeter methods under different salinities were also designed to measure the clay contents,through flow test cylinder, rotary viscometer and unconfined compression apparatus,the fluidity, viscous parameters and strength indices were tested.The salinity effects respectively on the basic characteristics of montmorillonite, illite and kaolinite were analysed, the variations of fluidity and strength indices for solidified clay minerals were also researched. The results indicate that the fluidity and strength indices of clay minerals exist significant differences.The effect of sodium chloride solution on the flocculation phenomenon of clay minerals and its influence on the hydration reaction of cement were finally investigated to provide mechanism analysis for the variations.2.Experimental research on the basic characteristics of natural clays and the fluidity and strength behavior of solidified clays under different salinities.The liquid and plastic limits and fluidity of two kinds of natural clays and the fluidity and strength of solidified clays weremeasured.The effects of initial water content, cement content and salinity on the fluidity,viscous parameters and strength of solidified clays were mainly analysed.It is Founded that with initial water content increased,the fluidity experienced two stages and the fluidity and viscous parameters correspond to each other.Moreover we used Origin software to fit the prediction formula between fluidity and viscous parameter.The influences of water cement ratio,salinity and other parameters on the flow behavior and stress-strain relationship of solidified clays were emphatically researched.The effect of salinity on the hydration reaction of solidified clays was analyzed by measuring the water contents of solidified clays.3.Mechanism analysis of seawater environment effect on fluidity and strength behavior of solidified clays.Through the influence of salinity on the liquid and plastic limits, fluidity and viscous parameters,the effects of salinity on the fluidity and the strength change of clays after solidification were analyzed.Meanwhile the basic physical properties of clay minerals and the fluidity and strength characteristics after curing with different salinities were compared.Finally the variations caused by physical and chemical reactions among cement, sodium chloride and clay minerals were discussed to explain the mechanism of engineering properties changes of solidified clays.