Experimental and numerical study on slotted loading Plates in tunnel boring machine thrust jacks

In tunnel drilling operations using tunnel boring machine (TBM), a relatively large concentrated load is applied by the device jacks to the prefabricated parts or segments of the tunnel cover. This load leads to significant tensile stresses in the segments. One of the most important parameters affecting the tensile stresses in the segments is the geometry of the loading plates of the trust jacks. In this study, with the aim of reduction of the values of tensile stresses in the segments, the innovative changes in the geometry of the loading plates of the propulsion jacks have been evaluated experimentally and numerically.