Figure 1
A simplified geological and structural map of the Polish Carpathians [5, 16, 23, 30].
Table 1
Physico-mechanical properties of sandstones [12].
| Rock type | Bulk density [Mg/m3] | Absorbability [%] | Dry condition compressive strength [MPa] | Compressive strength after water absorption [MPa] | ||||
|---|---|---|---|---|---|---|---|---|
| min–max | on average | min–max | on average | min–max | on average | min–max | on average | |
| Krosno sandstone | 2.31–2.71 | 2.64 | 0.25–3.70 | 1.50 | 57–178 | 122 | 40–153 | 89 |
| Magura sandstone | 2.50–2.69 | 2.62 | 0.30–2.47 | 1.12 | 91–207 | 164 | 59–194 | 125 |
| Cergos sandstone | 2.48–2.77 | 2.63 | 0.52–2.94 | 1.33 | 115–207 | 170 | 94–173 | 134 |
Figure 2
Los Angeles drum.
Figure 3
Sample before (a) and after (b) fragmentation test.
Figure 4
Micro-Deval drum.
Figure 5
Sample before (a) and after (b) abrasion test.
Figure 6
Histogram of beta distribution of resistance to fragmentation and abrasion: (a) Magura sandstone, (b) Cergos sandstone, (c) Krosno sandstone and (d) overall.
Table 2
Statistical values of LA and MDE coefficients for Carpathian sandstone aggregates.
| Value | LA coefficient | MDE coefficient | ||||||
|---|---|---|---|---|---|---|---|---|
| Overall | Magura sandstone | Cergos sandstone | Krosno sandstone | Overall | Magura sandstone | Cergos sandstone | Krosno sandstone | |
| Average | 26.69 | 24.54 | 23.67 | 41.32 | 40.15 | 35.53 | 37.36 | 62.95 |
| Minimum | 14.00 | 14.00 | 20.00 | 24.30 | 20.00 | 20.00 | 30.00 | 35.20 |
| Maximum | 56.00 | 37.10 | 28.60 | 56.00 | 84.20 | 58.50 | 47.00 | 84.20 |
| Standard deviation | 8.47 | 6.38 | 2.83 | 9.08 | 13.97 | 11.39 | 4.67 | 15.15 |
| Median | 24.30 | 23.35 | 23.10 | 41.00 | 38.10 | 35.15 | 37.40 | 66.00 |
| Coefficient of variation | 31.76 | 26.01 | 11.96 | 21.99 | 34.80 | 32.04 | 12.50 | 24.07 |
Figure 7
Function fitting for Magura sandstone: (a) linear, (b) exponential and (c) logarithmic.
Figure 8
Function fitting for Cergos sandstone: (a) linear, (b) exponential and (c) logarithmic.
Figure 9
Function fitting for Krosno sandstone: (a) linear, (b) exponential and (c) logarithmic.
Figure 10
Function fitting for all tested sandstones: (a) linear, (b) exponential and (c) logarithmic.
Figure 11
Regression analysis results: (a) linear, (b) exponential and (c) logarithmic.
Figure 12
Residuals for all tested sandstones: (a) linear, (b) exponential and (c) logarithmic.
Table 3
Regression statistics.
| Coefficients | R square | Standard error | t Stat | p-value | Lower 95% | Upper 95% | |
|---|---|---|---|---|---|---|---|
| Linear function | |||||||
| Intersection | 0.480 | 0,8129 | 2.139 | 0.224 | 0.822 | −3.773 | 4.733 |
| LA | 1.486 | 0.076 | 19.444 | 2.02E-33 | 1.334 | 1.638 | |
| Exponential function | |||||||
| Intersection | 6.634 | 0,7426 | 2.246 | 2.952 | 0.004 | 2.168 | 11.099 |
| exp^(0.034*LA) | 12.904 | 0.814 | 15.845 | 2.24E-27 | 11.285 | 14.522 | |
| Logarithmic function | |||||||
| Intersection | −103.338 | 0,8161 | 7.330 | −14.097 | 3.49E-24 | −117.908 | −88.768 |
| ln(LA) | 44.265 | 2.252 | 19.649 | 9.59E-34 | 39.788 | 48.743 | |