Laboratory tests were conducted on 12 different carbonate rocks to investigate index properties of deteriorated rocks due to physical weathering. Physical weathering due to freeze-thaw and thermal shock action for 20 cycles, was simulated, following the procedure suggested by standard methods. Index properties, P-wave velocity.. uniaxial compressive strength and Schmidt hardness, for the three series of the rock samples were determined for fresh, freeze-thaw and thermal shock conditions. It was found that the index properties of rocks treated with freeze-thaw and thermal shock decrease in varying levels with respect to initial values. A model equation predicting the index properties of rocks due to freeze-thaw and thermal shock treatment was developed by multiple regression analysis of measured data. This model explains decrease in index property of a deteriorated rock depending on its initial property and porosity of rock with the coefficients for a specific index property, given in the paper for the both freeze-thaw and thermal shock treatments. Model was validated by statistical tests. In order to estimate the index property for any cycle of freeze-thaw or thermal shock treatment, this model equation was incorporated into a previously suggested model to eliminate a decay constant required for that model to be determined for a specific rock in the laboratory. So, the final model equation could accurately predict a property of a deteriorated carbonate rock depending on treatment cycle, and initial index property and porosity. This was also proved by comparing the model with compressive strength data of a researcher for freeze-thaw cycles. (c) 2006 Elsevier Ltd. All rights reserved.