Modeling of minimum void ratio for sand–silt mixtures

Compaction Characteristics and Minimum Void Ratio Prediction Model for Gap-Graded Soil-Rock Mixture

“…Chang et al [23] considered the mutual inferences between fine-grained and coarse-grained particles when studying the minimum void ratio of sand-silt mixtures. They found that the added fine-grained particles would inevitably distort the structure of coarse-grained particles and cause a change of total void volume.…”

“…where e c is the void ratio of pure coarse-grained particles, e f is the void ratio of pure fine-grained particles, a and b are material constants. Chang et al [23] also proposed an equation for estimating the minimum porosity of the binary mixtures, as Equation (4). The minimum void ratio of gap-graded SRMs computed using Vallejo and Chang et al models are shown in Figure 11 and compared with measured values from compaction tests.…”

“…The change of total volume is ∆V, and it is caused by two parts, one is caused by the altering of the structure of coarse-grained particles ∆V A , the other is caused by particle breakage ∆V B , ∆V = ∆V A + ∆V B . (1) Calculation of ΔVA: According to Chang et al (2015), the change of void volume ΔVA caused by the added fine-grained particles is proportional to the amount of fine-grained particles added to the mixture. Therefore, ΔVA can be calculated using Equation 5.…”

“…where k1 and b1 are material constants. (1) Calculation of ∆V A : According to Chang et al (2015), the change of void volume ∆V A caused by the added fine-grained particles is proportional to the amount of fine-grained particles added to the mixture. Therefore, ∆V A can be calculated using Equation 5.…”

“…Studies show that the void ratio is closely related to the engineering properties of gap-graded materials, such as compressibility [20], shear strength [21] and permeability [22]. The existing void ratio prediction models are built mainly for sand-silt mixture or sand-clay mixtures [7,23]. However, SRMs have coarser particle sizes than sand-silt mixture and sand-clay mixtures, resulting in more particle breakage in gap-graded SRMs during compaction [24].…”