With reservoir drawdown, the groundwater table in the adjacent aquifer falls down correspondingly. It is useful to calculate the groundwater table variation as a function of time during reservoir drawdown for hydraulic and hydrological purposes. The Boussinesq equation with a moving boundary is applied to analyze the groundwater table variation in the unconfined aquifer during reservoir drawdown. This approach assumes a negligible seepage face. Because the moving boundary condition in the mathematical formulation precludes analytical solutions even for the linearized Boussinesq equation, we have transformed the Boussinesq equation into an advection–diffusion equation to address the negligible seepage face and the moving boundary condition. On the basis of the Laplace transformation, we yield an analytical solution of a fixed boundary problem, which is further simplified to upper and lower polynomial solutions for convenient practical use. The polynomial approximate solutions are satisfactorily compared wi...

The NaOH solution can activate the surface of soil particles and solidify each other at contact points to improve the mechanical strength of soil, therefor the alkali liquor reinforcement method has the advantages of simple construction, high reinforcement strength, good water stability and low cost, and is applicable to the reinforcement of cohesive soil foundation. For loess lacking calcium and magnesium ions, CaCl₂ solution should be added and can react with NaOH to form Ca(OH)₂ hydraulic cementing material which can significantly strengthen soil. The strength of soil strengthened by NaOH and CaCl₂ double solution reinforcement is 1/3~1/2 higher than that of single liquid reinforcement. As the operating load increases, it is necessary to reinforce the subgrade of a special railway line of Jinan city under the condition of normal traffic. The upgrading double liquid method is used for reinforcement and good results are obtained.

The problem of rock mechanics and engineering is an old and new subject encountered by human beings in their struggle with nature for survival and development

The sustainable development of green mining and geotechnical engineering has become a crucial area of study in light of the increasing global efforts toward environmental conservation and responsible resource extraction