论文部分内容阅读
通过大量试验,我们获得了松树脚矿岩石的强度、静弹性常数、动弹性常数、应力—应变曲线和扩容。所有试验均是通过单轴压缩下完成的。广泛采用了压缩、剪切和抗张试验。试件规格有5×5×5cm,5×5×10cm,Φ5×2.5cm。单轴压缩试验压缩方向平行于长轴。我们发现实际中因荷载形式不同,其岩体破坏优势没有单一的模式在试验中,我们研究了应力—应变曲线。研究岩石力学性质,最为普通的方法是通过对高为宽2倍的柱体进行轴向压缩得到的。大多数岩石应力—应变曲线都接近于线性形式。也就是说,应力—应变曲线满足关系σ=Εε。总应变等于三个轴向应变的总和εl+ε2+ε3。对于线弹性材料具有恒定的杨氏模量和泊松比,在压缩时总应变是直线变化且是正斜率,即由于ε1>|ε2+ε3|,总应变随压力增加而减小。当应力增加至强度的1/3～1/2值时,总应变开始偏离弹性材料的直线段。在临破坏前偏离直线的偏离量非常大,在这个压缩阶段岩石的总应变与线弹性材料的性质完全无关,即随应力增加,岩石体积有增大现象,也就是众所周知的扩容现象。在这种情况下,临破坏前,试件的侧向应变总和一定超过轴向应变值,即|ε2+ε3|>ε1,岩石试件在这种压缩试验下泊松比也不是常数。
Through a large number of tests, we obtained the strength, static elastic constants, dynamic elastic constants, stress-strain curves, and dilatation of pine foot rock. All tests were done under uniaxial compression. Compression, shear and tensile tests are widely used. Specimen specifications are 5 × 5 × 5cm, 5 × 5 × 10cm, Φ5 × 2.5cm. The uniaxial compression test compresses the direction parallel to the long axis. We found that in practice there is no single mode of rock mass destruction due to different load forms. In the experiment, we studied the stress-strain curve. The most common method for studying the mechanical properties of rock is obtained by axially compressing a column that is 2 times as tall. Most rock stress-strain curves are close to linear. That is, the stress-strain curve satisfies the relationship σ=Εε. The total strain is equal to the sum of the three axial strains εl+ε2+ε3. For a linear elastic material with a constant Young’s modulus and Poisson’s ratio, the total strain changes linearly and is positively sloped when compressed, ie due to ε1>|ε2+ε3|, the total strain decreases with increasing pressure. When the stress increases to 1/3 to 1/2 of the strength, the total strain begins to deviate from the straight section of the elastic material. The amount of deviation from the straight line before failure is very large. In this stage of compression, the total strain of the rock is completely independent of the properties of the linear elastic material. That is, as the stress increases, the volume of the rock increases, which is known as expansion. In this case, the total lateral strain of the test piece must exceed the axial strain value immediately before failure, ie, ε2+ε3|>ε1, and the Poisson’s ratio of the rock test piece is not constant under this compression test.