Prediction of Unconfined Compressive Strength of Soil–Cement at 7 Days

Unconfined compressive strength (UCS) of cement stabilized bases was collected from a number of highway construction projects in Thailand. Results from the statistical analysis indicated that the most important factors affecting the UCS were the CBR and the water to cement ratio. The UCS was however independent on the dry density. A statistical model was developed in the study to predict the UCS of cement stabilized bases. A model was developed based on the following criteria: (1) the dry density of the sample shall be greater than 95 percent of the maximum dry density based on the modified Proctor compaction, (2) samples shall be soaked for at least 2 h prior to testing, and (3) the CBR shall be measured at 0.1 inch (2.5 mm) penetration.