The basic principle of the three-dimensional stress state test is deduced based on the relationship between the normal stress and the conventional stress state, and the relationship between the total stress state and the effective stress state is given based on Terzaghi’s effective stress principle. On this basis, we made a three-dimensional earth pressure device by using a pedestal obtained by 3D printing technology, 6 micro earth pressure cells, a pore pressure cell and an attitude sensor. Considering the effect on the tested values of the dynamic change in the normal stress direction, the conversion relationship between the absolute test direction and the relative test direction of the test device is deduced, which can be used to dynamically test the three-dimensional total stress state and three-dimensional effective stress state. In addition, a method to calculate the K₀ value is proposed based on the earth pressure device comparing with the direct test result by the K₀ oedometer and indirect test results by direct shear test and triaxial test in laboratory. Two three-dimensional earth pressure devices are used in a simulation experiment of tailings dam construction, and the results show that with the increase in pore pressure, the calculated errors of the three-dimensional stress state caused by rotation angles will be more noticeable. This study has engineering value for in situ geotechnical testing and soil strength prediction.

根据正应力与常规应力状态之间的关系推导了三维应力状态测试的基本原理，并根据特扎吉的有效应力原理给出了总应力状态与有效应力状态之间的关系。在此基础上，我们使用3D打印技术获得的基座，6个微土压力盒，孔隙压力盒和姿态传感器制成了三维土压力装置。考虑到法向应力动态变化对试验值的影响，推导了试验装置的绝对试验方向和相对试验方向之间的转换关系，可用于动态测试三维总应力。状态和三维有效应力状态。此外，提出了一种基于土压力计的K ₀值，并与K ₀里程表的直接测试结果和实验室的直接剪切试验和三轴试验的间接测试结果进行了比较。在尾矿坝施工模拟实验中使用了两个三维土压力装置，结果表明，随着孔隙压力的增加，旋转角所引起的三维应力状态的计算误差将更加明显。该研究对原位岩土试验和土强度预测具有工程价值。