Study On Creep Properties Of Calcareous Sand Considering Particle Breakage

As sea power theory is put forward,and protect the Marine military strength rising steadily,the engineering development of the south China sea and reef construction in China are increasingly wide attention by scholars,and calcareous sand as one of the important basic material in the construction of the south China sea,study its unique mechanical properties,especially for the Marine environment and the engineering practice of triaxial creep mechanical characteristics,has become the research hotspot and difficulty in recent years in our country.At present,there have been abundant achievements in the study of one-dimensional creep characteristics of calcareous sand,while few achievements in the study of triaxial creep characteristics of calcareous sand are in the preliminary stage.Because of calcareous sand is a kind of easy broken constitution of granular materials,in addition to the ambient pressure,axial stress in the heart of the ocean environment,such as bearing the external load,also more comprehensive considering the compactness of calcareous sand for creep behavior of calcareous sand triaxial,so in this paper,the south China sea a sea of calcareous sand as the research object,on the premise of considering particle breakage of calcareous sand has carried out a series of different compactness of calcareous sand material in different ambient pressure conditions were imposed a variety of axial load of indoor triaxial creep test study,elaboration to explore the relative compactness,the pressure and the axial stress around three factors such as the influence of Triaxial creep property of calcareous sand,The effects of particle breakage on the creep mechanism of calcareous sand are analyzed and recognized,and the triaxial creep equation of calcareous sand is constructed on this basis.The main research contents and conclusions of this paper are as follows:(1)To carry out the calcareous sand particles morphology analysis,determination of grain size distribution and relative compactness,gravimetry,obtained a series of basic physical property parameters,analysis of calcareous sand particles morphology found surface and internal contains abundant irregular pore,its different particle size,shape,and through the determination of particle size distribution of the experiments on screening the best time,and the appraisal conclusion sandy category.(2)Through indoor calcareous sand,triaxial creep test,to get its creep test data,and in the case of control variables,the different compactness,confining pressure,the environment,no axial load under the condition of calcareous sand specimen,the comparison research,analysis of above three factors of calcareous sand respectively the influence of triaxial creep deformation.(3)Through the fitting analysis of triaxial creep test data,the strain law of calcareous sand in creep stage was obtained.(4)The particle morphology of calcareous sand before and after triaxial creep test was obtained by using a microscopic camera,the corresponding shape parameters were extracted for comparison,and the triaxial creep mechanism of calcareous sand was analyzed by combining the Hardin particle breakage potential theory.(5)The triaxial creep equation of calcareous sand was constructed on the theoretical basis of the experimental data and the stage and integrity characteristics of triaxial creep obtained,and the one-dimensional creep theory of calcareous sand was taken as the basic framework.The triaxial creep equation of calcareous sand had a high degree of fit with the experimental data,which played a good role in predicting and characterizing the triaxial creep deformation of calcareous sand.