Research On Reinforcement And Treatment Technique Of Roadbed On Squashy Foundation In The Flooded Area Of Yellow River Of Eastern Henan

The landform of the Flooded Area of Yellow River(FAYR) of Eastern HenanProvince belongs to the plain formed by the deposit of the quaternary. The stratumsis sedimentary facies which is alleviation flooded by the Yellow River. The soilquality is soft, has great moisture capacity, high compressibility, thixotropy and lowshear strength. Thus, it is regarded as squashy foundation. As a result, it is necessaryto reinforce it to ensure the access to the public. The paper presents a systematicanalysis on the reinforcement technique of roadbed on the squashy foundation inFAYR with the help of the latest researches and engineering experience of bothdomestic and abroad. Because it is liable to suffer serious roadbed diseases causedby building high-grade highway on the base of the squashy foundation.First, the paper reviews the latest researches on the reinforcement technique ofroadbed on the squashy foundation. On the base of investigating and analyzing thedamage of the squashy foundation of high-grade highway in Eastern Henan, it isresearched the geologic and terrene characteristics and project reality. The paperputs forward the thoughtway about "treatment layer of the basement" and providesfour solutions to reinforce and treat roadbed on the squashy foundation. They arehardcore bed method, lime and cement-stabilized soil method, geogrid method andthe combination of lime-stabilized soil and geogrid method respectively.Secondly, the paper applies the theory of four-dimensional analysis ofsettlement and provides the settlement measurement for multi dimensionalnon-linear deformation. Software named GSCP is used for calculating the settlementof roadbed by terrene parameter from the soil test. The method of ContactFinite-element is used to deal with the settlement and stability of reinforcedfoundation by geogrid.Finally, the paper provides a practical focus on geogrid and makes a detailedstudy of four treatments for the squashy roadbed from aspects of principle, designand construction. They are used to the practice of changing over to new way of G310in Kaifeng. By means of the settlement observation analysis, it is found that thetesting results are quite identical to the theory and all the indexes meet the demandsof road rules and regulations in force. On the basis of analysis on the result ofenforcement and treatment, by the means of technological economy analysis, geogridis found to be optimum in the aspect of technological economy and applied to thetreatment of foundation of the total line. Also, the paper provides three appraisal indexes (settlement of embankment, thespeed of settlement and non-uniform rate of settlement) for the effect of treatment. Itis researched on the method to calculate the future settlement too. The valuessuggested and calculating formulas are been made, and hopefully it will providesome references for the design and construction of the identical project in the sameregion.