The Shear Strength of Granite Weathered Soil Under Different Hydraulic Paths

Abstract

At present, there is no clear understanding of the influence of differences in soil mineral composition, particle size grading, and hydraulic paths on the shear strength of unsaturated soil, and the related strength models are not applicable. The shear strength characteristics of different saturation specimens under different hydraulic paths were studied on two granite weathered soils. The experimental results show that the shear strength index of the prepared specimen is “arched” with the increase of saturation, and the dehydration specimen decreases linearly with the saturation. As considering the cementation of free oxides in soils and the interaction among soil particles at different saturations, it is assumed that there are three different contact modes among soil particles: direct contact, meniscus contact, and cement contact. The difference in contact modes will reflect the different laws of shear strength. A shear strength model capable of distinguishing between the capillary effect and the adsorptive effect was established. The model predicted and verified the shear strength data of granite weathered soil under different hydraulic paths well, and then theoretically explained the evolution law of the shear strength of granite weathering soil under the change of saturation.

Investigating the Shear Strength of Granitic Gneiss Residual Soil Based on Response Surface Methodology

“…Given this shortcoming, the response surface methodology (RSM), a mathematical and statistical technique that optimizes the experimental results by approximately developing a explicit polynomial expression, provides a corresponding strategy that enables the complicated connection between the required response and input factors to be ascertained [21]. Moreover, it allows a minimization of the number of experiments and the level of independent variables, and offers internal error estimates [22].…”

Study on The Influence of Grain Size Composition on Engineering Properties of Granite Residual Soil

“…The difference of parent rock type and weathering degree in different regions jointly results in the obvious regional characteristics of grain size composition of granite residual soil. Even in the same area, due to the weakening of the topdown weathering degree, the grain size composition is also very different [20][21][22][23]. The difference of grain size composition has a significant impact on the structure and engineering properties of granite residual soil, but there is a lack of targeted research [24].…”