Abstract: To investigate the effect of cement content on the Guilin Red Claycement mixtures, an extensive laboratory test program was developed. Mixture samples with different cement content and age on the strength and microstructure changes were tested with the unconfined compressive strength and analyzed with scanning electronic microscope (SEM). The results indicate that the clay particles formed the granular and needle like materials after adding cement. These soilcement reaction products can fill, connect and cement clay particles and formed harder soil aggregate, therefore, improve the strength of soilcement mixture. When the cement content is less than 20%, the increase of cement content can accelerate the form of harder aggregate and increase the early strength of mixtures. The strength of the mixture increases with the curing age. When the cement content is greater than 20%, the harder aggregate has formed with certain amount of cement and therefore, the increase of cement content will not significantly increase the strength of soilcement mixtures.

Key words: Curing Age, Cement Content, Strength, Microstructure