Purpose This paper aims to present a simplified solution method for the elasto-plastic consolidation problem under different stress paths. Design/methodology/approach First, a double-yield-surface model is introduced as the constitutive model framework, and a partial derivative coefficient sequence is obtained by using numerical approximation using Gauss nuclear function to construct a discretization constitutive model which can reflect the influence of different stress paths. Then, the model is introduced to Biot’s consolidation theory. Volumetric strain of each step as the right-hand term, the continuity equation is simplified as a Poisson equation and the fundamental solution is derived by the variable separation method. Based on it, a semi-analytical and semi-numerical method is presented and implemented in a finite element program. Findings The method is a simplified solution that is more convenient than traditional coupling stiffness matrix method. Moreover, the consolidation of the semi-infinite foundation model is analyzed. It is shown that the numerical method is sufficiently stable and can reflect the influence of stress path, loading distribution width and some other factors on the deformation of soil skeleton and pore water pressure. Originality/value Original features of this research include semi-numerical semi-analytical consolidation method; pore water pressure and settlements of different stress paths are different; maximum surface uplift at 3.5a; and stress path is the main influence factor for settlement when loading width a > 10 m.

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A contactless inspection using a household digital camera (close shot photogrammetry) is introduced to improve measurement of wind-drifted snow distribution on the lower roof of a stepped flat roof model. Based on the image processing technique, a series of wind tunnel tests under different wind directions are investigated. Then 3-dimensional coordinates of the target points are calculated. Two typical directions are presented and discussed. The calculation results indicate that snow distribution on the lower roof appears to be concave when it is on the windward side. The maximum snow depth is located at the step, and the magnitude is about 2.78 order of the average snow depth. When the lower roof is on the leeward side, the distribution appears to be convex. The maximum depth located 1.0H away from the step, and the magnitude is about 1.2 order of average depth.

The character of geomaterials is affected by stress path remarkably. Under different stress paths, the stress-strain characteristics of geomaterials are difference. For the unloading path in existing engineering situation, the physical parameters and constitutive model is usually determined by loading test. The path to uninstall the actual project conditions which may be a larger error. Therefore, this work proceeding from the actual project, deep excavation of the lateral unloading condition is analysed. The tests of CTC path and RTC path on silty clay in Huangshi city of china by multi-path tri-axial plane strain are carried on in the geotechnical Engineering Laboratory of Huangshi Institute of Technology. Then, the phenomenon under the two stress paths are compared with each other and describing the differences between them. The mechanical properties in the RTC stress path is analyzed mainly. Based on the Cam-Clay model framework, then derived this material yield equation based on Cam-clay model, Laiding the foundation for the numerical analysis.