A method of measuring the pressure-volume relationship of mortar using a thick-walled cylinder

A method for measuring the pressure-volume relationship of mortar is presented, involving axial compression of a mortar specimen in a thick-walled cylinder (TWC). Hoop strain at the outer wall of the TWC is measured to determine the average radial stress ( σ r ) in a mortar specimen according to TWC theory. Axial stress ( σ a ) of mortar is measured using a load cell. The pressure ( P = σ a + 2 σ r 3 ) acting on the mortar specimen is determined from the measured axial and radial stresses. Separately, axial displacement is measured to determine the current specimen volume. TWC was designed to measure mortar pressures exceeding 100 MPa within the elastic deformation regime of the TWC. Feasibility of the proposed method and influence of friction on the measured pressure-volume relationship were examined via a finite element simulation, followed by experimental manifestation of proposed method. The proposed method was found to be effective for measuring the pressure-volume relationship of mortar. • A method for measuring the pressure-volume (P-V) relationship of mortar is presented. • The P-V relationship is measured using the thick-walled cylinder (TWC) and its theory. • A TWC was designed to measure mortar pressures up to around 100 MPa. • The influence of friction on the measured P-V relationship can be corrected. • The friction correction relies on measuring loads at the top and bottom of the specimen.