Test And Analysis On Influence Of Rheological Phase Material On Soft Soil Rheological Property

Soft soil is a complex natural porous media, which is widely distributed in the coastalareas, rivers, lakes, wetlands and other areas. In recent years, with the economic developmentand urbanization level continue to improve, development and use of soft soil engineeringcontinue to evolve. A large number of engineering experience and research show that thedeformation of soft soil takes a long time to stabilize. The rheological properties of soft soil,which stress-strain develops as time change, may make the building (structure) built on softsoil cause unignorable construction settlement, and thus pose security stability problems. Inthis paper, the means of combining experiment and theoretical research is used to analyze thefactors and mechanism which affect the physical strength and rheological properties of softsoil from the microscopic point of view.Through the strength and rheological properties experiments of different microscopicparameters combinations of sandy soil and soft soil samples, this paper analyzes the inherentrelationships between microscopic parameters and parameters of strength and rheologicalproperties, explores the mechanism that affects the sandy soil and soil strength characteristics,interprets different rheological properties between sandy soil and soft soil base on vanrheology and fluid rheology. Finally, on the basis of experimental analysis, the impact of theshape and distribution of rheological phase material on the rheological properties is explored,and the correctness of corresponding conclusions through numerical simulation calculation isverified.The outline of the research tasks and achievements of this dissertation are listed asfollows:(1) The research of strength characteristics of different size composition, the mineralcomposition and water content of sandy soil and soft soil are carried out. Based on theexperimental analysis, the particle size distribution of sandy soil is an important factoraffecting its strength characteristics; while for soft soil, the adsorption and friction,cementation between different mineral particles is the determining factor of its strengthcharacteristics. In addition, the change between particles surface water film thickness andnature will change the adsorption and friction, cementation mechanism between the particles, thereby changing its strength characteristics.(2) The impact of soil composition on the rheological properties are analyzed throughdirect shear creep test. The test results shows that the particle composition and stress levelwill produce a more significant impact on the rheological properties of sandy soil, and watercontent to some extent will affect rheological properties; clay minerals, oxides, organic matterand bound water of soft soil are important material factors that affect soft soil rheology, and itproduces a significant impact on the rheological properties of soft soil by adsorbing boundwater to particles surface. But the impact of the rheological characteristics of the soil bydifferent components is different; the nature of bound water will have an important impact onthe rheological properties, the impact of strong bound water on rheological properties is moresignificant than that on weak bound water.(3) The four-phase rheological material theory is used to explain the mechanism of sandyand soft soil from the substance. The soil is divided into van rheology and fluid rheology,rheology of sandy is mainly influenced by the rheological stress level and size components,deformation stability required for a short time, performance van rheological characteristics.While the soft soil rheology is mainly affected by clay minerals, organic matter, oxidecolloids, bound water and other substances content, the longer the time required fordeformation stability, performance liquid rheological characteristics.(4) Through laboratory creep test and numerical simulation, the influence the shape anddistribution to rheological properties are analyzed. Experimental and numerical results showthat when material flow in disguise uneven, the impact of the shape and distribution on therheological properties is significant, but as material flow increasing uniformity, the impact ofshape and distribution waning, rheological properties gradually transit to associate only withnature and proportion of the material flow in disguise, and regardless of its shape and thedistribution of forms.