CAJ | 학술논문

通过分析盐岩在三轴应力状态下的变形，说明了较高围压下盐岩的大变形特性，提出了三轴应力状态下，利用轴向荷载除以试件初始横截面面积得到应力-应变关系存在的问题，据此对工程应变和对数应变进行了分析和对比，阐明了这两种应变的适用条件，并开展了不同围压下的试验测试和对试验结果对比分析。研究揭示了应利用对数应变分析盐岩的大变形特性和对变形后的应力进行修正，得到了盐岩的工程应变和对数应变均可表示为围压的线性函数，围压为20 MPa时的轴向压缩变形量是5 MPa时的3.09倍。围压越高，对数应变修正得到的最大轴向应力与不修正的差值越大，用对数应变修正后的轴向应力低于不修正的结果，围压达到20 MPa时，前者仅为后者的63.85%。
통과분석염암재삼축응력상태하적변형，설명료교고위압하염암적대변형특성，제출료삼축응력상태하，이용축향하재제이시건초시횡절면면적득도응력-응변관계존재적문제，거차대공정응변화대수응변진행료분석화대비，천명료저량충응변적괄용조건，병개전료불동위압하적시험측시화대시험결과대비분석。연구게시료응이용대수응변분석염암적대변형특성화대변형후적응력진행수정，득도료염암적공정응변화대수응변균가표시위위압적선성함수，위압위20 MPa시적축향압축변형량시5 MPa시적3.09배。위압월고，대수응변수정득도적최대축향응력여불수정적차치월대，용대수응변수정후적축향응력저우불수정적결과，위압체도20 MPa시，전자부위후자적63.85%。
Through analyzing the salt rock deformation under triaxial compressive stress condition, the large compressive deformation properties of salt rock under higher confining pressure are shown. The problems of the axial stress-strain obtained by axial load divided by the initial cross-sectional area of the specimen are pointed out for triaxial compressive tests. Thus the engineering strain and logarithmic strain are analyzed and compared;and the applicable conditions of these two strains are explained. Finally, the triaxial compressive tests for different confining pressures are carried out and the test results are compared. The research results shows that the logarithmic strain should be used to analyze the large deformation property and the modification of axial stress for salt rock when the larger deformation occurs. The deformation obtained by logarithmic strain and engineering strain for salt rock could be expressed as a linear function of confining pressure. When the confining pressure is 20 MPa, the axial compressive deformation is 3.09 times that of 5 MPa. The higher the confining pressure is, the larger difference of the maximum axial stress is between obtained by the initial cross-sectional area and the logarithmic strain corrected area, and the latter is less than the former. When the confining pressure is up to 20 MPa, the maximum axial stress for the logarithmic strain correction area is only 63.85%of that for the initial cross-sectional area.