Effects of heating on the hydraulic and poroelastic properties of bourgogne limestone

This experimental work aims at studying the influence of temperature on mechanical behaviour and poro-mechanical properties of an oolitic limestone from Anstrude, France. This program follows a previous hydraulic and poro-mechanical study on the same intact material-i.e. which had not been heated. Close agreement was found between direct measurements of poro-mechanical properties and their theoretical values. The Anstrude limestone has been oven-heated at two temperature levels (150 or 250 °C) in order to evaluate possible thermal effects such as micro-cracking. Macroscopic properties such as porosity and permeability do not show notable differences, and no visible cracks are observed with microscopic observations. However, strength limit and poro-mechanical properties (measured with a non-nil pore pressure) vary after thermal treatment. This may be evidence that micro-cracking occurs at a lower scale than that used for the microscopic observations, and is able to influence the undrained behaviour of the material.