A circular concrete shaft liner with Young’s modulus of 23.45GPa, Poisson’s ratio of 0.25, unconfined compressive strength 24.1 MPa, and tensile strength 2.41 MPa is loaded to the verge of failure in dry ground. If the inside shaft diameter is 6.7 m and the liner is 0.3 m thick, what is the contact pressure between rock and liner, assuming it is uniform (in kPa)?