Solar radiation causes changes in the temperature of the rock surface and its interior. These changes can lead to irregular expansion and contraction and the creation of thermally induced stress, that lead to the formation of cracks and the propagation of existing ones.
A field experiment that quantifies these effects under natural conditions can be a useful tool for understanding these processes and improving existing models. However, natural rocks have a high level of variability and homogeneity, which makes it difficult to create consistent results in experiments. Moreover, it is difficult to measure the temperature changes that develop within a rock block. Therefore, for the purpose of the study, we are interested in using an artificial block made of concrete. Using an artificial rock that simulates a natural rock, we can overcome these limitations by controlling the level of homogeneity. In addition to the physical properties, the use of artificial concrete block also provides control over the geometry and allows reproducibility of the experiment.
In this study, we aim to find a composition that has similar properties to natural rocks. We will examine different mixtures in concrete castings, which will be tested in a laboratory for mechanical and thermal properties. The most suitable mixture will be used in the model castings of the experiment. The artificial rock experiments will be located in a number of different places in Israel under different climatic exposure conditions. The experiment will use various sensors to quantify the heat flux at the rock surface into the interior of the rock and the resulting strain and cracking.
Understanding the thermal effects on rocks under natural environmental conditions is expected to advance our understanding of the mechanism of rock weathering on geological time scales.