Abstract: This paper derives theoretical expressions of the external loads and crack opening displacements of concrete wedge-splitting specimens under hydrostatic pressure, based on the initial fracture toughness criterion and the Paris displacement formula. And a numerical iterative method is used to simulate the specimens’ full fracturing process, focusing on analyzing the effect of water pressure, particularly the sensitivity of the peak load parameters and the opening displacement parameters of critical cracks under different water pressures. The results show that the full crack propagation curves calculated using this method agree well with the experimental measurements. Water pressure and initial crack length affect load-displacement curves. With an increasing water pressure, both peak load and critical cracks’ opening displacement are reduced; with an increasing initial crack length, more obvious is the influence of water pressure on the full process curve of crack propagation.

Key words: concrete, wedge splitting tensile specimen, hydrostatic pressure, initial toughness, crack