Abstract: To limit the tool damage of shield when cutting the concrete diaphragm wall, four types of pick cutters are designed according to the cutting technique in the coal mining industry using different tapers of the cutter head and arc lengths of cutter tip. The cutting trace is determined via simulation, and the distance between the two adjacent cutting traces is set over 18 mm. Then, the cutting test is conducted on C35 concrete. The following are the test findings: (1) The cutting force decreases with the decreasing tool arc lengths and taper, and the impact of tool taper is smaller than that of tool arc length. (2)The tool arc length and taper slightly affect the positive component force. (3) The tool arc lengths significantly influences the tangential component force; the tangential force and torque decrease with the decreasing tool arc length, thus decreasing cutting efficiency. The cutting tool with a taper of 40° and a arc length of 5 mm is chosen as the experimental tool to perform a simulation test of C35 glass fiber reinforced concrete based on preliminary experimental findings and tool durability. The cutting effect of the designed tool is compared to that of the threedimensional shell cutter, and the comparative findings demonstrate that the pick cutter can effectively avoid the cutterhead jamming when using shell cutter; its cutting ability is better and the peak torque is efficiently controlled. However, the pick cutter is too small, leading to a total shear fracture.

Key words: pick cutter, tool taper, tool arc length, concrete diaphragm wall, cutting efficiency, cutting test