Experiment of a Hard Rock Excavator by Using an Edge Excavation

Blasting method is a conventional method for hard rock mass excavation. Recently, the use of blasting method is getting difficult due to environmental problems, such as noise pollution and ground vibration. Mechanical excavation method is an alternative for the blasting method; however, the present excavation method has two problems: the low efficiency due to the wear of cutting bits and the high cost to exchange cutting bits. Thus, through this research, we are trying to innovate the edge excavation method in order to solve the two problems. The purpose of this study was to develop a rock excavator attached to backhoe by using multistage edge excavation method. We carried out the experiments by using model excavator to find out its efficiency and force acting on the rock excavator. In this study, we conducted a basic experiment by using a displacement controlling method to determine the load required to control a model excavator. The specimen used was high-strength mortar specimen. In the experiment, a model excavator was attached to the experimental device, and the speed was set to be constant by displacement control. Excavation was performed by rotating the specimen. The vertical force F_z, torque T, excavation depth z, and soil volume m, the excavation time t were measured. As a result, the load required for the model excavator was verified and the capability of the experiment to be performed through load controlling was confirmed.