Study On Soft Clay Solidified Material And Its Solidified Soil Properties

With the development of society,land resources are becoming increasingly scarce,resulting in a sharp decrease in human living space.In order to alleviate the related pressures,reclamation has become an essential way for human beings to expand their living space from land to sea.China has a prolonged coastline and plenty of islands,which provide favorable conditions for China’s land reclamation projects.However,after reclamation,the site is mainly composed of soft clay with large natural water content,high compressibility,low strength,and poor permeability.If it is directly used as an engineering foundation without any treatment,it will lead to disasters such as landslides and foundation instability,causing economic losses and casualties.Stacking a large amount of soft clay is bound to bring about environmental pollution,space waste,and relatively high transportation costs.In order to address these issues,one of the commonly used soft clay treatment methods is to use traditional materials such as cement for solidification.However,these solidified materials are expensive and easy to produce greenhouse gases such as CO₂ during production.Therefore,consider using industrial waste instead of cement to solidify soft clay to achieve the effect of turning trash into treasure and low green carbon.Therefore,this thesis has researched soft clay solidified materials and their solidified soil properties.The main research contents are as follows:（1）Proportioning study of soft clay solidified materialsAccording to the characteristics of soft clay,blast furnace slag,quicklime,and sodium silicate were selected as curing materials.Through the single mixing test,compound mixing test,and orthogonal test,the influence of different curing materials on the properties of solidified soil was analyzed,and a composite curing material（named XZ23 composite curing material,the best ratio of three curing materials was 5.83:2.08:2.71）was obtained.The curing effect and economy of XZ23 composite curing material and cement were compared and analyzed by soft clay curing test.The mechanism of XZ23 composite curing was studied by SEM test.（2）XZ23 solidified soil strength theory establishmentBased on the pozzolanic effect of solidified materials and the classical strength theory of cement soil,the pozzolanic coefficient and equivalent cement theory of solidified materials were proposed.The influence of solidified materials on solid soil strength is quantitatively analyzed.The effects of curing age and water-cement ratio on solidified soil strength were studied.Finally,the strength prediction formula of solidified soil related to curing age and the water-cement ratio was obtained.（3）Verification of the road performance of XZ23 solidified soilThe road performance of XZ23 solidified clay was verified by the water stability and dry-wet cycle test.It is found that although water has a great negative effect on the solidified soil,the water stability and dry-wet cycle of XZ23 solidified soil are quite effective,which can meet the strength requirements of shallow solidification.（4）Practical application of XZ23 solidified soil in road engineeringBased on the development of the cultivated land project in Wenzhou City,Zhejiang Province,the application of XZ23 solidified soil in practical engineering was studied.The project uses ABAQUS to establish a three-dimensional finite element model and compares the calculation results with the monitoring results.It is found that the effect of using XZ23 composite curing material to solidify soft clay is remarkable,and it has good economic value and social benefits.