Test Study On The Mechanical Property Of The Aeolian Sand And The Bearing Capacity Of The Aeolian Sand Ground Of Mu Us Desert

Based on the comprehensive study of natural geographical and geological conditions of Mu Us Desert, and a series of tests and test means, this paper studies such physical properties of Mu Us Desert eolian sands as grading characteristics, microstructure, density and water content, and also such rock-soil mechanical properties as compression, compaction and strength. At the same time, this paper discusses the hysteretic properties and change trends of soil-water characteristic curves under different density conditions, measures the permeability of Mu Us eolian sand, studies the changing relationship between osmotic coefficient and density, and provides relevant calculation parameters for the numerical simulation calculation of finite element.On the basis of studying the stress-strain-strength relationship under the conventional stress paths, this paper realizes the triaxial stretching stress path test by improving the conventional triaxial test apparatus. In this paper, relevant parameters of D-C non-linear elastic constitutive model and constitutive model of Cambridge have been determined through relevant test data after the study of stress-strain-strength relationship under the stress path, which provides relevant parameters for the numerical calculation of Mu Us Desert eolian sand project based on the two constitutive models above.This paper studies the state-based elastoplastic constitutive and related constitutive parameters concerning the Mu Us Desert eolian sand. Starting with the introduction of deformation property of Mu Us Desert eolian sand, this paper first studies its state and determines relevant model parameters, then verifies the constitutive model by focusing on the state-based constitutive model theory of eolian sand dilatancy. Based on the triaxial test results under different stress paths, this paper simulates the deformation properties of Mu Us desert eolian sand under different stress paths, and compares them with experimental results, discussing the applicability of this model and existing problems under different stress paths.On the basis of consolidated undrained (CU) and consolidated drained (CD) dynamic triaxial tests, dynamic characteristics of Mu Us Desert eolian sand are studied. Based on the analysis of relevant dynamic parameters, dynamic strength properties and influence factors, this paper establishes the equivalent viscoelastic constitutive and residual strain model of Mu Us Desert eolian sand, obtains the equivalent strength parameters, and makes the criterion for equivalent Mohr-Coulomb strength. This paper provides experimental and theoretical basis, models and parameters directly for engineering applications for the deformation of Mu Us Desert eolian sand foundation under dynamic loads, strength calculation, and site liquefaction potential discrimination.This paper carries out the work of testing the bearing capacity of Mu Us Desert eolian sand foundation, and studies its bearing properties. Aiming at the ultimate bearing capacity of gravel piles, sand piles and cement mixing pile bodies on the Mu Us Desert eolian sand layer, and that of composite foundation, this paper carries out lots of in situ load tests and testing work, and equally studying the characteristics of load sharing between piles and soils of pile-body composite foundation, and effective length of single pile, which provides an important test basis for the design and construction of Mu Us Desert eolian sand foundation.