## 4 Results
### Tensile Strength  
The experimental results show that the peak strength of all of the remolded loess specimens varied from 1.31 to 115 kPa and demonstrate that the tensile strength of remodeled loess was significantly influenced by its water content and dry density (Figure 10). For the same water content and dry density, the tensile strength of the DM specimen was consistently greater than that of the WM specimen, with the strength difference between the two groups becoming more profound as the water content decreased, as is indicated in Figure 10.  
Figure 8: Tension deformation process obtained from PIV analysis.  
Figure 9: The typical tensile stress–strain curve for the brittle failure mode.  
The variations of the tensile strength with the water content for the DM and WM samples with different dry densities are presented in Figure 11. In terms of the DM specimens, the tensile strength generally increased as the water content decreased and it can be seen from Figure 11a that there exists a critical water content (\(w_{c}\)) of about 18% which divides the overall variation curve into two different regimes. It was noted that the \(w_{c}\) value is close to the plastic limit of the loess. When the water content was greater than \(w_{c}\), the tensile strength increased very slowly with the decrease in the water content; when the water content was less than \(w_{c}\), the tensile strength increased very rapidly (at a higher rate of increase) as the water content decreased. These observations imply that the proximity of the water content to the plastic limit leads to a substantial change in the factors contributing to loess' tensile strength. The variation with the water content of the tensile strength of the WM specimens, however, showed a dissimilar tendency. As is demonstrated in Figure 11b, the tensile strength initially increased as the water content increased to 10% and it then decreased quickly with the further increases in the water content. A boundary water content of 10% that separates the two different trends can be identified and the tensile strength achieved its peak value at this water content. It is commonly believed that an increase in the water content leads to a decrease in soil suction and, hence, the cohesive forces between soil particles, which induces the reduction of soil's tensile strength. However, Figure 11b indicates that this common understanding seems not to be applicable to the WM specimens with relatively low water contents (<10%). The water distribution status in loess and the associated microstructure evolution with water content change should be considered to be an important reason accounting for the tendency that is shown in Figure 11b, which will be discussed later.  
Figure 11 also indicates that, for a given water content, the tensile strength, overall, increased with the increase in the dry density. Moreover, the role of the dry density varied  
Figure 11: The variation of tensile strength with water content for (**a**) DM specimens and (**b**) WM specimens.  
Figure 10: The overall trend for the tensile strength to vary with water content (\(\rho=1.6\) g/cm\({}^{3}\)).  
with the range of the water content. For the DM sample, the rate of increase in the tensile strength with the decreased water content increased with the dry density in samples with a water content of between 18% and 26%. When the water content was less than <18%, the slope of the tensile strength curve increased as the dry density increased from 1.4 g/cm\({}^{3}\) to 1.6 g/cm\({}^{3}\) and then it remained almost unchanged with a further increase in the dry density to 1.8 g/cm\({}^{3}\), as is illustrated in Figure 11a. With respect to the WM sample, the slope of the tensile strength versus the water content curve is not affected by the dry density at a water content of less than 10% (Figure 11b); when the water content was higher than 10%, the rate of decrease in the tensile strength with increased water content increased with the dry density.