In recent years, construction has increased at previously uninhabited high altitudes with the development of winter tourism and population growth. Therefore, it is necessary to examine the soil behaviour at low temperatures and high altitudes. This study investigated the physical properties and mechanical behaviours of soil samples collected from four mountainous regions, including settlement areas. In addition, new frost- heaving pressure and strength prediction charts have been developed. Based on sieve analysis, the soil samples from the Ka & ccedil;kar, Paland & ouml;ken, Erciyes, and Ilgaz Mountain areas were classified as silty gravel or sand. With increasing elevation, the percentage of coarse particles in soil samples increased, whereas the proportion of fine particles decreased. A new device was developed to investigate the mechanical behaviour of soil samples at low temperatures (0 degrees C and below). The highest frost strength (7274.5 kPa) and heaving pressure (43.97 kPa) were measured in soils with high fine-grain content. A statistical evaluation of the test results was performed, and it was determined that the most influential variables for estimating frost heaving and strength were the fine-grain ratio, soil temperature, and water content. ANN analyses were performed using these variables, and ternary strength and frost-heaving pressure estimation diagrams were developed.

Biodegradable polymer-based bags were developed as an alternative to plastic. However, their degradation in environmental conditions has not been fully investigated and is often incomplete. Here, the decomposition of three types of biodegradable bags and one type of plastic bag in different types of environments was analyzed. Polymer bags were exposed for six weeks in water, soil, air and compost, while the control groups were stored in room conditions. All types of polymer bags were sampled twice (after 3 and 6 weeks), and different parameters of changes in physical-mechanical properties were measured. The research established significant differences in changes in mechanical properties between different types of biodegradable polymer bags, with 'white' and 'brown' bags showing the best decomposition potential. As expected, the largest change in the structure and physical-mechanical properties of all types of polymer bags was recorded in compost, and the smallest in air and water.