Abstract：In consideration of the requirements for nonlinear mechanical behaviors of soft rock at depth，the development of a new experimental system for rock mechanics is discussed，which can perform the multiple composite tests of tension-compression and tension-shearing under the conditions of different loading processes including the common function such as uniaxial tension，shearing，uniaxial and triaxial compression tests. To overcome the deficiency of the current experimental system (for rock mechanics) that cannot perform the composite tests of tension-compression，tension-shearing，and different loading or unloading process simulations，the main structures and functions of the system，the technical indexes，and the key technologies to achieve satisfactory experimental results such as reduction of friction force technology，equal-transmitting force technology，and stress-concentration elimination technology，etc.，are introduced. The presented new experiment system can provide a new method to further study of mechanical behavior of rock mass at depth.
