Quartz #1

Quartz #1 is formed by mechanical crushing of quartzite rock. Quartz Sands are denoted as #1 by the distributor AGSCO, Inc, the number represents a size order. The material is classified as SP according to ASTM Unified Soil Classifications System (USCS). Particles of Quartz #1 are angular as shown in Fig. 4.67. Selected DIA images of Quartz #1 are also presented in Fig. 4.68.

Grain size distributions of Quartz #1 are presented using several size descriptors in Fig. 4.69. Fig. 4.70 also depicts variation between number and volume distribution. The size of number distribution is dominated by the finer particles while volume distribution is dominated by the larger particles. The grain size D50 of Quartz #1 is 320 µm. Typical particle size diameters in µm corresponding to several particle size descriptors are presented in Table 4.46. Comparison between EQPC sizes corresponding to various particle size diameters by weight/volume and number distributions are also presented in Table 4.47. A large number of finer particles were generated during the crushing process, which resulted in a difference between number and volume distribution calculation.

The density distribution for a number of commonly used shape descriptors is presented in Fig. 4.71 and summarized in Table 4.48. The distribution is clearly non gaussian and is thus fit with Johnson’s parameters. The fitting parameters are summarized in Table 4.49, and the goodness of fit is depicted in Fig. 4.72.


Fig. 4.67. Photo of Quartz #1 sand with a 19 mm diameter US Penny for scale.

Fig. 4.67. Photo of Quartz #1 sand with a 19 mm diameter US Penny for scale.


Fig. 4.68. Images of Quartz #1 acquired using 2D DIA.

Fig. 4.68. Images of Quartz #1 acquired using 2D DIA.


Table 4.46 Typical particle size diameters in µm corresponding to several particle size descriptors (by weight/volume distribution).

Quartz #1 D1 D5 D10 D30 D50 D60 D90 D99
Feret-max 87 246 305 375 419 443 559 754
EQPC 62 178 229 285 320 335 411 513
Feret-min 56 142 184 244 277 293 357 434


Table 4.47 Typical EQPC corresponding to various particle size diameters by weight/volume and number distributions.

Quartz #1 D1 D5 D10 D30 D50 D60 D90 D99
Volume 62 178 229 285 320 335 411 513
Number 3 3 4 5 8 10 31 298


Table 4.48 Statistics of particle shape descriptors for Quartz #1 by number and volume distributions.

Quartz #1 AR S Cx Rwadell
Number
Mean 0.64 0.79 0.93 0.65
Median 0.65 0.80 0.93 0.66
Standard Deviation 0.14 0.07 0.03 0.12
Volume
Mean 0.64 0.79 0.93 0.64
Median 0.66 0.80 0.94 0.66
Standard Deviation 0.14 0.07 0.03 0.12


Table 4.49 Johnson fitting parameters for Quartz #1.

Quartz #1 γ δ ξ λ
AR -0.79 1.35 0.09 0.89
S 3.39 2.09 0.92 0.05
Cx 1.52 1.24 0.96 0.01
Rwadell -1.04 1.65 0.08 0.88


Fig. 4.69. Particle size distributions using various size descriptors.

Fig. 4.69. Particle size distributions using various size descriptors.


Fig. 4.70. Particle size volume and number distributions.

Fig. 4.70. Particle size volume and number distributions.Fig. 4.71. Particle shape density distributions (based on volume) for Quartz #1.

Fig. 4.71. Particle shape density distributions (based on volume) for Quartz #1.

Aspect Ratio - Fig. 4.72.1
Sphericity - Fig. 4.72.2
Convexity - Fig. 4.72.3
Wadell Roundness - Fig. 4.72.4

Fig. 4.72. Johnson fitting of shape descriptors for Quartz #1.