## 3 Results and Discussion
### Normalization of Experimental Results from the Literature and Model Analysis
#### 3.1.2 Plastic Soils  
The results of repeated triaxial tests on soil plasticity performed in the studies by [PERSON] and [PERSON] [31], [PERSON] [54], and [PERSON] et al. [55] were used to assess the PWP excitation modes of plastic soils. In the three aforementioned studies, different PI values, FCs, confining pressures, strain controls, and CSRs were used. The present study inspected the characteristics and differences in the PWP excitation of plastic soils. According to the experimental results, the PWP of the non-plastic sandy soils rapidly reached the level of initial liquefaction, suggesting that the liquefaction resistance of the soils was relatively low. However, when the cyclic number exceeded 20, the high-plasticity specimens did not reach initial liquefaction, indicating that the liquefaction resistance increased with increasing plasticity. The PWP data of plastic specimens approaching the initial liquefaction obtained from the three studies were normalized. If initial liquefaction was not reached, the cyclic number was adjusted accordingly until initial liquefaction was reached. First, to examine the behavior of low-plasticity soils under repeated loading, [PERSON] [54] collected undisturbed soil specimens from the Fraser River in Canada and subjected them to cyclic triaxial testing. The specimens were silty sandy soils with PI values of 7. The water contents of specimens FRS-100-017, FRS-100-020, FRS-100-029, FRS-300-015, FRS-300-017, and FRS-400-015 were 36.8%, 36.2%, 38.7%, 40.3%, 40.1%, and 40.1%, respectively, and their initial void ratios were 0.990, 0.974, 1.041, 1.083, 1.078, and 1.078, respectively. The soils with higher water contents had higher void ratios. The numbers 100 and 300 in the names of the specimens were used to distinguish specimens with an experimental compaction stress of approximately 100 and 300 kPa, respectively. Different repeated shear ratios and confining stresses were used in the experiments. The PWP data were consistent with the WP excitation mode of plastic soils. The Ru and normalized N/N\({}_{\text{L}}\) values are shown in Figure 8a. To explore the effect of plastic fines on changes in PWP during vibration, [PERSON] et al. [55] subjected samples of mixed Monterey soils and kaolinite to cyclic triaxial tests. Kaolinite fines were added at concentrations of 10%, 20%, and 30% by weight. The G\({}_{\text{s}}\), LL, PL, and PI values of the kaolinite were 2.58, 41.7%, 26.2%, and 15.5, respectively. The grain size of 70% of the kaolinite fines was smaller than 5 um, and the USCS classification of the kaolinite was CL/ML. Shear strains of 0.1% and 0.3% were used. The Ru and normalized N/N\({}_{\text{L}}\) values are mapped in Figure 8b. To investigate the stress-strain and PWP behavior of soils in Adaparzari, Turkey during earthquakes, [PERSON] and [PERSON] [24] collected undisturbed soil specimens from ten  
Figure 7: The \(\beta\) value in the model developed by [PERSON] et al. [42] should be between 0.45 and 2.0 in comparison with experimental data between red and blue solid lines. boreholes in eight different locations in Adaparzari and subjected them to repeated triaxial tests. The failure criterion was set to a strain of 2.5% or an Ru value of 1. The 10 specimens included non-plastic soils with a PI = NP and plastic soils with a PI of 40. The experimental results revealed the effects of plastic fines on PWP at roughly the same CSR. The Ru and normalized N/N\({}_{\text{L}}\) values are mapped in Figure 8c. The basic parameters and soil classifications of the four thin-tube specimens were as follows: (1) T5-1 (thin tube number): PI = 40%, CSR = 0.40, and CH; (2) T6-3 (thin tube number): PI = 39%, CSR = 0.41, and CH; (3) S6-1 (thin tube number): PI = 23%, CSR = 0.42, and CH; and (4) T7-1 (thin tube number): PI = 19%, T7-1, CSR = 0.40, and CL. The curve shifted toward the lower right as the PI value decreased. Figure 8a-c was compiled into 8d, in which the PWP ratios and normalized N/N\(\vdash\) values are mapped for comparison.