# Modeling Undrained Shear Strength of Sensitive Alluvial Soft Clay Using Machine Learning Approach
## 2 Materials and Methods  
The soft clay is located in northern areas of the Nile River, in Egypt. The sensitive clay was formed in alluvial sediments. For the ML model study, 111 soft clay samples were collected from the northern Nile delta. The data set included geotechnical features of natural water content (\(W\)), dry unit weight (\(\gamma_{d}\)), liquid limit (\(LL\)), plasticity index (\(PI\)), consistency index (\(CI\)), void ratio (\(e\)), specific gravity (\(Gs\)), and pocket penetration shear (\(q_{p}\)). The utilized features were easily determined or calculated from the geotechnical laboratory tests. The performed experimental tests were natural water content, specific gravity, bulk density, liquid and plastic limits, and Pocket penetration, according to ASTM numbers D 2216, D 854, D1556, D 4318, and WK27337, respectively. The latter tests are traditional geotechnical tests, and are also more cost-effective and less time-consuming. Moreover, the adopted dataset was selected because the included soil features significantly influence the undrained shear strength of the studied soft clay. For example, increasing the natural water content causes a decrement in the cohesive force between soil particles, which leads to a weakening of soil consistency and reduces shear strength. Increasing dry density leads to a minimizing of the pores between soil particles and void ratio, causing an effective increment in the undrained shear strength. The void ratio of soil not only affects its permeability, but it also significantly influences the undrained shear strength of the soil. The increments of the liquid limit, plasticity index, and consistency index offer strong evidence for the existence of clay content. Consequently, increasing clay content in soft soil directly increases its undrained shear strength. Specific gravity is considered the main factor in predicting shear strength. Pocket penetration shear value represents an important indication of the undrained shear strength of the saturated cohesive soil value, which has a significant correlation with the undrained shear strength of the sensitive soft clay. It is known that determining undrained shear strength, either in the field or in the laboratory, is highly difficult. Moreover, several problems were faced in extracting undisturbed samples of sensitive clay. According to the unified soil classification system, the sensitive clay soil was categorized as a high plasticity clay (CH). The classification of CH in soft soil was a result of the high values of the plasticity index. The liquid limit and plasticity index ranged from 46% to 103%, and from 20% to 69%, respectively. The natural water content ranged between 40% to 71%, as illustrated in Figure 1 and Table 1. The undrained shear strength of the clay was determined by field vane shear tests (ASTM D2573-08) [21]. The vane test was suitable for the studied soil, having saturation conditions and a soft consistency. The field van shear equipment is shown in Figure 2. The results of the undrained shear strength stated that the sensitive clay ranged from very soft to soft soil (5 kPa-45 kPa). The sensitivity values of the clay were between 2.5 and 28.6, as depicted in Figure 3. Clay sensitivity was the ratio of the undrained shear strength in the field to that in the laboratory, for the same soil. According to the sensitivity classification of [PERSON] and [PERSON] (2014) [20], the current study soil included low, medium, and high  
In this study, we considered eight input features to create an ML predictive modeling of the soft clay soil. The datasets were initially preprocessed to eliminate any outliers that were commonly observed in realistic datasets.