LBI, NJ Sand

LBI sand was obtained by the authors from Ship Bottom beach on Long Beach Island (LBI) in New Jersey. It is classified as a mixture of sub-angular and sub-rounded particles, as shown in Fig. 4.115. Selected DIA images of LBI, NJ are also presented in Fig. 4.116.

Grain size distributions of LBI sand are presented using several size descriptors in Fig. 4.117. Fig. 4.118 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 LBI, NJ is 470 µm. Typical particle size diameters in µm corresponding to several particle size descriptors are presented in Table 4.78. Comparison between EQPC sizes corresponding to various particle size diameters by weight/volume and number distributions are also presented in Table 4.79.

The density distribution for a number of commonly used shape descriptors is presented in Fig. 4.119 and summarized in Table 4.80. The distribution is clearly non gaussian and is thus fit with Johnson’s parameters. The fitting parameters are summarized in Table 4.81, and the goodness of fit is depicted in Fig. 4.120.

Fig. 4.115. Photo of LBI, NJ sand with a 19 mm diameter US Penny for scale.

Fig. 4.116. Images of LBI, NJ acquired using 2D DIA.

Table 4.78 Typical particle size diameters in µm corresponding to several particle size descriptors (by weight/volume distribution).

LBI, NJ	D1	D5	D10	D30	D50	D60	D90	D99
Feret-max	263	343	387	479	562	612	862	1336
EQPC	216	288	329	401	470	505	700	1135
Feret-min	189	255	281	356	412	451	639	1043

Table 4.79 Typical EQPC corresponding to various particle size diameters by weight/volume and number distributions.

LBI, NJ	D1	D5	D10	D30	D50	D60	D90	D99
Volume	216	288	329	401	470	505	700	1135
Number	3	4	4	6	9	13	350	595

Table 4.80 Statistics of particle shape descriptors for LBI, NJ by number and volume distributions.

LBI, NJ	AR	S	Cx	Rwadell
Number
Mean	0.74	0.86	0.96	0.74
Median	0.75	0.87	0.96	0.75
Standard Deviation	0.10	0.05	0.02	0.09
Volume
Mean	0.74	0.86	0.96	0.73
Median	0.75	0.87	0.96	0.73
Standard Deviation	0.10	0.05	0.02	0.09

Table 4.81 Johnson fitting parameters for LBI, NJ.

LBI, NJ	γ	δ	ξ	λ
AR	-0.47	1.33	0.38	0.62
S	2.25	1.86	0.93	0.04
Cx	1.07	1.34	0.97	0.01
Rwadell	3.89	3.95	1.01	0.24

Fig. 4.117. Particle size distributions using various size descriptors.

Fig. 4.118. Particle size volume and number distributions.

Fig. 4.119. Particle shape density distributions (based on volume) for LBI, NJ.

Fig. 4.120. Johnson fitting of shape descriptors for LBI, NJ.