MTS815.04试验系统拥有优良的加载系统、控制系统、测量系统等，是当今岩石力学测试研究领域的主要设备之一。基于该系统配置的轴向和侧向变形引伸计测试原理，对应用中出现的一些测试技术问题进行了深入研究。首先，基于原有链式侧向变形引伸计测试技术改进了原有的侧向应变计算方法；对轴向变形测试中岩样峰后曲线部分非常规问题进行了合理的解释，并提出相应的改进方法；最后，建立了一套专门针对变形传感器的多功能标定器具和标定方法。这些测试技术的改进为开展室内非常规岩石力学试验研究提供了试验条件和保证。

 MTS815.04 testing system is one of the most excellent equipments in the field of current rock mechanics testing research for its outstanding loading system, controlling system and measurement system. Based on the principle of extensometer measurement in axial deformation and lateral deformation configured by MTS system, some questions on postpeaking strength curves emerged from applications of deformational measurement techniques are reasonably interpreted. Firstly, the original lateral strain calculation methods are improved on the basis of the original chaining type of lateral extensometer measurement techniques. Some problems on axial deformation measurement method are discussed and the improved method is put forward. At last, a type of extensometer calibration technique for deformation sensor is proposed. All the measurement technical improvements can provide testing condition and guarantee for laboratory rock mechanical testing research.