Experimental Study on the Variation of Tunnel Roof Plate Buckle Steel Pipe Support with Vertical Rod Lifting Axial Force

In recent years, the disc buckle steel pipe support is more and more widely used in tunnel roof construction. when the axial force monitor is installed in the conventional way, the monitors can not accurately judge whether there is a void between the monitor and the main keel, resulting in a great difference in the axial force value of the adjacent vertical rods and the lack of axial force monitoring accuracy. In this paper, it is proposed that the corresponding axial force value should be adjusted with the concrete pouring. Through the actual monitoring case, the change of the corresponding axial force value in the monitoring vertical rod lifting process of the disc buckle steel pipe support is obtained, and compared with the axial force value calculated by the vertical rod theory, the axial force monitoring method of the disc buckle steel pipe vertical rod is explored. The results show that: (1) compared with the conventional monitoring methods, this paper proposes that the actual force of each vertical bar can be actively controlled by actively adjusting the corresponding vertical rod axial force value. (2) according to the load theory, the calculated value of the axial force of the vertical rod is basically consistent with the actual axial force monitoring value, which verifies that the actual axial force monitoring value of the frame is safe. (3) there is a linear relationship between the lifting H value of the vertical rod and the axial force increment value FX of the vertical rod. The research results are of reference value for conventional high-supported formwork monitoring and construction.