Construction and Geotechnics

Currently construction projects are becoming more complex and modernized, acquiring new quality standards which is due to the growth of the industry and the use of new information technologies. Meeting modern requirements including ensuring reliability and safety is possible through the use of the latest software tools for processes such as modeling and optimization of structures. Software products enable engineers and architects to design innovative designs that meet the latest design requirements for reliability, safety and cost-effectiveness. New technologies and analysis methods allow for more detailed modeling of structural behavior taking into account a variety of operating conditions. Genetic algorithms and artificial intelligence are becoming key tools for optimizing structures using structural mechanics methods. Research in the field of structural engineering plays an important role in contributing to the development of structural mechanics in general, taking into account reliability, safety of projects, industrial development and compliance with quality standards. Software technologies are an integral part of modern structural mechanics, providing engineers with powerful tools for analyzing and calculating building structures. The advantage of software technologies is to increase productivity, reduce the number of errors and collisions. Modern information technologies allow engineers to improve the quality of calculation substantiation of design decisions, reduce the material consumption of a construction project, reduce project deadlines and economical costs. The paper discusses the finite element method and provides an overview of computer modeling programs developed for the calculation and design of structures in the field of structural mechanics. The results of research on the use of genetic algorithms and artificial intelligence are demonstrated and the features of the operation of these technologies are given.

For the insulation of underground structures, the creation of protective screens in hydraulic structures and on waste storage tanks sand-bentonite mixtures are successfully used. Unlike natural clay soils they are characterized by homogeneity of composition, workability, high deformation and strength characteristics, lack of shrinkage, etc. As a rule, mixtures are prepared from dry ingredients. The purpose of this present research was to study the possibility of preparing and determining the properties of mixtures of sands with a saponite-containing suspension - a waste product of concentration of the diamond-bearing ore from the settling pond of the tailings of one of the enterprises in Arkhangelsk region. Saponite is a clay mineral belonging to the same group as montmorillonite, which predominates in the composition of bentonite. For the preparation of mixtures four types of sands of different composition and genesis were used. The studied mixtures in terms of water permeability turned out to be almost identical to sand-bentonite mixtures, for example, the introduction of 16 % saponite-containing waste ensured a decrease in the filtration coefficient of sands to (1.2…15.3) · 10-5, and 24 % - to (0.4…2.0) · 10-5 m/day. There were obtained experimental dependencies of the filtration coefficient k from effective or free porosity ne and degree of pore blocking in the sand matrix δ . The first value is found by excluding from the pore volume the volume of water sorbed by highly dispersed clay and dusty-clayey particles contained in the sand, and the second value is found as the ratio of the volume of clay, dusty particles and moisture sorbed by them to the volume of pores between sand particles. The use of the studied mixtures, for example, for the installation of screens on industrial and domestic waste storage tanks, will significantly reduce costs due to the use of industrial waste and sands from local quarries, as well as the absence of the need for preliminary drying of materials.

The problem of influence of water saturation on values of strength characteristics of eluvial mudstone-like clays and sandstones has been considered in the article. During water saturation of such soils significant deterioration of their strength properties can be observed. This complicates the process of arranging foundations on such bases. The purpose of this work is to compare the values of the strength characteristics of mudstone-like clays and sandstones of Perm city at natural humidity and in a fully water-saturated state. To achieve this goal, the following tasks have been solved: 1) the analysis of the problem study has been carried out; 2) laboratory testing methodology has been developed; 3) the results of laboratory tests have been processed and compared with the available data of tests on the field section; 4) the conclusions of the study have been formulated. According to the results of laboratory tests on a single-plane section, a decrease in the angle of internal friction by 28 % for water-saturated mudstone-like clays and by 23 % for sandstones was revealed. The decrease in cohesion values as a result of water saturation was 29 % for mudstone-like clay and 33 % for sandstone. According to archival data from field tests of mudstone-like clay pillars, the angle of internal friction decreased by 24.2 %, and the specific adhesion decreased by 65.4 %. The results of field and laboratory tests showed a significant decrease in the strength characteristics of mudstone-like clays and sandstones when saturated with water. The authors recommend performing foundation calculations on highly weathered mudstone-like clays and sandstones of Perm taking into account the possible deterioration of the construction properties of these soils. Assessment of the stability of slopes composed of weathered mudstone-like clays and sandstones requires an integrated approach and taking into consideration possible changes in the properties of these soils during water saturation.