| Respect to the development and state of art of concrete slab-faced rockfill dam, this thesis point out that the rheology of rock -fill should be studied not only in the application aspect, but also in the theory itself.. A four parameter rheological model, which is related to stress state, is proposed based on rheological experiment and data analysis. Through analysis of uni-axial creep test and tri-axial rheology test result, it is concluded that the volumetric rheology obeys the same rule as shearing rheology so that the same relation can be used to describe their mechanical behavior. The mechanism of rockfill rheology is rectified theoretically. As a kind of man-made discrete material,the rockfill is similar to the consolidated soil in the aspect of rheology. The main causes of rockfill rheology are the breaking and sliding of particles, filling of pores. The breaking of rockfill particles is decomposed into breaking due to compression and breaking due to rheology, corresponding to vibration compaction and rheological fineness respectively. The rheological breaking is relatd directly to stress and temperature. The relation between rheological breaking ratio and plastic work is set up according to the equation relation between outer plastic work and energy of plastic deformation. It is helpful to the understanding of elasto-plastic constitutive relationship of rockfill and braking of particles.Based on analysis of test result, in-site observation data, this paper put forward a quantitative relation between rheology and valley shape, rockfill mechanical parameters, such as dry density, compressive modulus, softening factor, pore ratio, etc. The main factors influencing the rheological behavior of rockfill can be classified into inner factors and outer factors. The inner factors refer to the mechanical behavior such as the rock type, density, construction parameter, etc. And the outer factors refer to the foundation condition, geological condition, valley shape, rise and fall of water level, seepage due to respiration. For high slab-faced rockfill dam, the old concept that any material can be put" on the dam should be discarded. The construction standard should not be decreased for the rockfill zone. The construction standards used for main rockfill zone and other zone should not too different to induce overly large rheological deformation.The rehological deformation will result in change of strength of the filling material. During the rapid rehological deformation period, weak filling material was broken and getting finer, the strength decreases at the same time. In the stable deformation period, the fine particles fill up the pores so that the strength increases slowly. The long term strengthprediction method is put forward under the assumption that cohesion C varies in the same way as friction angle , and shearing stress varies in the same way as normal stress.The paper compares some models of elastic, elastic-plastic and rheology which describes the relationship of stress and strain.It is regarded that produces dilation and breakage due to the outer forces. The stress and strain of rockfill happens under the twice action of dilation and breakge. Based on elastic-plastic model , and considered some relationship between volumetric rheology, shearing .rheology and. time, the paper studies rheology of rockfillwith Yin Zongze Model, of two yield surface and rheological relation of negative exponential, and some formulas are obtainedIt is difficult to determine the rheological parameters, of rock fills through laboratory test for the limited specimen, dimension, short duration and particle, constituents. Comprehensive parametric recognition method is proposed. The method works in this way. Firstly, basic data are obtained form laboratory tests or back analysis then initial result is obtained through empirical judgement, engineering comparison, at last, the rheological parameters.used in computation are obtained after comprehensive analysis and judgment. The method is used.to analyze Cethana...
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