In this paper we describe a numerical model of transient water flow in unsaturated expansive soils and the resulting soil volume change. The unsaturated flow equation is solved in a 2D domain using a finite-volume method and an explicit time discretization scheme. Strains in the soil mass are calculated by two simplified approaches, assuming that the strain state is either 1D (in the vertical direction only) or 2D with equal strains in horizontal and vertical directions. The model is applied to two cases described in the literature, in which the strains were computed from the solution of the stress equilibrium equation. It is shown that the simplified methods give results which are reasonably close to the more complex approach based on the equilibrium equations. The proposed model can be used to predict time-varying soil shrinkage and swelling caused by natural and anthropogenic factors.
To consider the optimization of the supply chain, a company operating in the cosmetics and hygiene industry was selected. It is a typical production company with foreign capital, working on entrusted material which entirely belongs to the parent company. The company management, purchasing and sales department are located at the parent company, the Polish branch is entrusted only with production and direct distribution of finished goods. The purpose of the work is to present the applied logistic solutions, characterize and analyse the existing supply chain and to propose actions to optimize currently used methods.
The aim of this paper is to determine the impact of human activity on the soil formation at the mouth of the Vistula Cross-Cut (northern Poland). The detailed research was conducted in the test area (about 500 ha) for which the soil map was created. The three major soil belts were distinguished, grouping the soils formed on marine, aeolian and technogenic sediments, deposited both naturally and anthropogenically as a result of the hydrotechnical works. Initial soils, arenosols, gleysols, brackish marsh soils and industrial soils predominate across the study area. Most of them were characterized by high spatial diversity and multi-layering. Their properties reflected varied dynamics of the local environment on both sides of the river channel, greatly enhanced by the human activity. Based of the obtained results, some proposals concerning arenosols, marsh soils and industrial soils for the Polish Soil Classification (2011) were presented.
The paper presents results of pedological studies of Klembivka site 1 and Prydnistryanske site 1 barrow IV and the reference soil profile Prydnistryanske site 1 in the context of pedostratigraphy, basic soil properties, construction material origin and palaeoenvironmental implications.