Portland cement (PC) is a central component in civil construction that significantly impacts greenhouse gas emissions and energy consumption. To mitigate these environmental effects without compromising the materials performance of cement-based materials, several strategies have been developed to lower the Global Warming Potential by enhancing PC efficiency. One such approach is to improve the packing density (PD) of the mixture and introduce a factor which describes the distance between PC particles Recent research suggests that this spacing factor is a more accurate predictor of concrete compressive strength than the traditional water-to-cement (w/c) ratio, particularly for low-PC-content designs. This paper presents two algorithms, that quantify the distance between PC particles. One is based on random particle placement and the other on particle positioning via gravitational settling based on the physical Discrete-Particle-Method. The performance of these models is assessed by comparing algorithmic outputs with empirical strength tests of cementitious pastes whose packing densities are computed with the Compressive Packing Model. The evaluation demonstrates a correlation between the calculated PC particle spacing and the compressive strength of the pastes.