Changing a layer of weak soil in deformed foundation with a compacted soil bed consisted of various strong materials (sand, gravel, pebble-gravel, production waste materials). Existing calculation methods and techniques to build compacted soil beds based on weak highly compressive soils do not meet up-to-date requirements. Calculation methods used the dimensions of compacted beds quite often appear to be overestimated, and this results in increase in costs and working hours needed to build artificial foundation. The paper presents the possibility of using reinforced soil beds as an efficient method to build artificial foundation based on weak soils.

The major part of seismically active Central Asian countries is presented by large-scale sub-mountain upland areas with complex engineering and geological conditions and surface topography as a rule. Plains and flatlands (valleys) in Tajikistan and Kirgizstan account for 10%, and all the rest areas are presented by mountains. Lack of agricultural area is considered to be a pending problem and calls for urgent solution. One of the efficient ways to solve this problem is to develop sub-mountain (hilly) areas which can make it possible to increase level of agricultural production and expand areas for buildings construction. The article deals with sub-mountain development experience based on the case of Tajikistan which can be valuable for different regions.

The motion of strong earthquakes causes nonlinear deformation and damages to the structure. For structural systems of buildings, domestic and European (EC8) regulation apply algorithm of seismic design based on reference linear-elastic methods that are carried out in two phases. Phase I includes determination of dynamic characteristics of structure, which are then used in phase II for calculation of seismic effects. In this study, parametric analysis of influence of dynamic characteristics of structure was done on multiple numerical examples, according to domestic and EC8 regulations and comparison of results.

The clay loams of semi-solid consistency was tested under static loads. The test results have proved that high values of soil density can change operating conditions of artificial foundations significantly, i.e. a so-called plate effect can be observed. Due to high hardness values highly compacted soil beds allow distributing foundation loads on the considerable part of the area and reducing its value on the edge of the weak layer.

Reliable construction and maintenance of buildings and structures based on weak and highly-compressive soils are closely related to artificial methods of how to prepare for foundation works. And changing a layer of weak soil in deformed foundation with a compacted soil bed consisted of various strong materials (sand, gravel, pebble-gravel, slag, production waste materials and others) can be considered as one of efficient methods. With the existing calculation methods used the dimensions of compacted beds quite often appear to be overestimated, and this results in increase in costs and working hours needed to build artificial foundation. It is more rational to create highly compacted and reinforced soil beds. The article deals with the general outcomes of experimental and theoretical research on design and foundation works of these beds which give evidence of their efficiency and explicit possibilities to expand fields of application.