The adjusted porosity/cement index eta/(C-iv)(a) has proved its effectiveness in modelling the strength and stiffness of a variety of artificially cemented soils. In this regard, by establishing a specific eta/(C-iv)(a) value, either by increasing the cement content and decreasing the density (or the opposite), a similar mechanical response is expected. Nonetheless, the role of this sort of dosage changing has not yet been verified for triaxial testing and, particularly, the effect of different dosages assembled at the same eta/(C-iv)(a) value has not yet been evaluated considering the effective peak stress parameters. As a reason, present research fulfills this gap by conducting a series of CID triaxial tests on a cemented clayey sand and, as well, small strain stiffness tests and the unconfined compressive strength tests. The last two being part of a preliminary assessment which comprehended the study of, at least, three dosages assembled at five different eta/(C-iv)(a) values. The test data have revealed that both the stiffness and the strength outcomes could be properly correlated to the eta/(C-iv)(a), regardless of the dosage type. Yet, the effective peak stress parameters (phi(peak)' and c(peak)') could not be related to the eta/(C-iv)(a) index owing to the dosage-dependence of the strength mobilization mechanisms.