The Research Of Non-integral Order Element Combination On Creep Model Of Rock Soils Under Low Temperature

There are not same creep properties are not the same with different rock mass in different environments, many scholars have been done lots of experiments and summarized in the soft rock soil and rock soil mechanics, such as clay, loess, and more concentrated in the compressive stability and rheological properties of rock and soil, but the use of the method and theory are different at all, considering the subject to the selection of theory model and the complexity of the optimization process, the studies on the creep of mudstone, mudstone in frozen diatoms, especially the optimization of structure and parameters of the model are still with a room, because of that, in order to make K-B model getting a more accurate description of deep frozen soil creep characteristics in the northeast region, currently selecting soil-mudstone and mudstone specimens of the diatom representative as the analysis object. It is particularly important to analyze the influence of temperature, load, soil type and time on the creep deformation of the complex environment (mainly considering low temperature) and geological conditions.Reasonable soil constitutive relationship is should be built on the basis of lots of creep tests, combining the necessary of components to model theory and the introduction of new algorithm and theory of fractional derivative, it is that the establishment of specific element model to study and analyze the mechanical properties. The expansion strength and creep test are inplemented by using the self-developed frozen soil testing machine on the specimen under three temperature levels (-5℃,-10℃,-15℃) and three loading coefficient (0.3,0.5, 0.7), the analysis that with its impact and a variety of environmental factors and the corresponding creep model fitting are compared, then getting the applicability of the model parameters.To integer order Nishihara creep model as the foundation, useing the improved simulated annealing optimization algorithm to optimize the processing, fractional Nishihara creep model, the parameters of the model should has characteristics of treatment, relatively simple form, with a certain unity. Through the comparison of integer order West primary creep model and optimization of fractional derivative West primary creep model, it can be found that the creep simulation of the phase has a high correlation, especially in the vicinity of the simulation curve inflection point. Not at all, the parameters that need to adjust in the calculation of the process is relatively small, a full description of the fractional derivative creep model of rationality has undeniable ability to predict the engineering significance in the field of on-site construction.