Abstract
A current challenge in unsaturated soil mechanics is the need to estimate ground heave and associated shallow foundation movements in expansive soils due to water content changes. Such estimation should be simple for geotechnical engineering practitioners and provide reliable foundation designs through quantifying the risk associated with the ground heave. The difficulties in generalizing a method are related to several variables influencing the expansive behavior, including the initial and final stress state condition, soil mineralogical composition, ground wetting depth, soil wetting degree, and geotechnical profile comprising soil strata thickness and groundwater condition. In this research, the evaluation of heave movements for the expansive soils located in the north-east of Tunja (Colombia) is performed through surrogate path (SPM), water content, and consolidation theory-based methods. Initial and final suction profiles were defined to quantify the wetting strains developed at each scenario of partial wetting. The sensitivity of the SPM to the estimated or measured value of constant volume swelling pressure was corroborated. The higher deformations that the soil profile would be able to develop when subjected to a progressive wetting were obtained along with the remaining heave capacity of the soil profile. Finally, concluding remarks and recommendations associated with the practicality and applicability of the methods are presented.
Highlights
Expansive soils are materials susceptible to volumetric changes due to variations in their water content
The method of Fredlund and Xing[13] with the fitting parameters models of Chin et al [14] and Zapata [15] was used to obtain the Soil Water Characteristic Curve (SWCC) of the expansive soils in the north-eastern sector of Tunja (Colombia) from the limited experimental data of matric suction obtained through the Filter Paper tests, the evaluation of the degree of saturation of the material and the index properties
The results obtained in terms of the total ground movement and remained heave capacity that the soil profile could potentially develop if changes in its water content occur, are consistent with the thickness of expansive soil, the magnitude of the pressures, and the percentages of both total and partial expansion obtained in each scenario
Summary
Expansive soils are materials susceptible to volumetric changes due to variations in their water content. As a result of the review of the state of the art of the topic under study, the odometer-suction methods and the Surrogate Path Method (SPM) were selected Those are practical and straightforward techniques that comprehensively include many of the previously mentioned factors influencing heave development and magnitude. The method performs interpolation from the volume change-suction net stress space to the net stress plane The ratio in which the suction is dissipated is analyzed in the method as a proportionality factor Rw from which it is possible to estimate the final net stress, ߪ′′ , at point P This point represents the net stress path, the final swelling pressure developed by the sample for the evaluated partial wetting conditions. The research was conducted in 6 steps that will be explained in detail below, along with the obtained results
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
