The building structures considered in the paper are plates. Plates are three-dimensional material objects, which are described by two-dimensional models. Plates have some specific qualities. Two-dimensional models, where displacements, deformations and stresses are described by two-variable functions. These functions are determined in a plate’s mid-surface. In case of periodically heterogeneous plates the two-dimensional description is much more difficult due to the fact of a non-linear and oscillating coefficients present in the model equations. The aim of the paper is to provide a brief description of a homogenous modeling method, i.e. the method of averaging those coefficients to make them dependent the diameter of a basic cell only. By the use of that method static and dynamic equations result in constant coefficients. As an example, using this described model, we submitted the precise result for a simply supported plate which is periodically heterogeneous in two dimensions.

The paper present analysis of soil behavior under shallow foundation using finite element procedure. The source code have been written in Mathematica language. The soil is modeled as linear elastic material. Computations have been carried out for three types of foot: Smooth flexible, rough rigid and smooth rigid. The results of the performed analysis were compared to the results of calculations by the computer software Midas GTS NX.

The object of analysis is a heat conduction problem within the frames of tolerance modelling in multicomponent, multilayered composites with functional gradation of effective material properties. The equations of proposed model for considered composites are partial differential equations with slowly-varying coefficients. The one-dimensional, stationary problem of heat conduction in direction perpendicular to layers will be analysed.

The article is directed to the researchers of building partitions, designers and people, who prepare certificates of building energy performance. The preliminary results of experimental test obtained for a single-layer brick wall are described. The experimental determination of the surface heat transfer coefficients inside and outside the building partitions is presented. The values of surface resistances and heat transfer coefficients obtained from test are differ from values included in PN-EN ISO 6964. The influence of the surface heat transfer coefficients on thermal transmittance is described. The article explains the importance of the surface heat transfers and resistances at the building partitions of different thermal resistances.

The study attemps to determine the optimal recipes based on cement, fly ash and two superplasticisers of new generation which would be able to fulfill space between the pipes in renovation of pipelines by relining. Inject recipes were selected taking into account the most favourable rheological properties of injects. There were flow time from the viscometer, time of spread at the distance of 100 cm, time needed to achieve the maximum spread. Moreover, initial setting time, shrinkage and compressive strength after 28 days were determined. It was found that the type and amount of superplasticiser and cementto-fly ash ratio affect the rheological properties of the injects. Relatively easy laboratory methods used for measurements of rheological properties made it possible to select optimal recipes of injects which in technical scale fulfill space between the pipes successfully.

The amount of the used waste rubbers in the world has been increasing every year, and their utilization, become a major environmental problem worldwide. The present experimental work has been performed to investigate the influence of rubber inclusion on the behavior of a sand. Geotechnical properties of the sand, and sand with tire crumb at various ratios mixtures (0, 2.5, 7.5, and 15%) were investigated through a series of mechanical tests, which are sieving, permeability, direct shear and consolidation. From the results of conducted tests, it is revealed that the addition of tire crumb grains increased both the permeability and the compressional characteristics of the sand. Besides, in this work, intergranular void ratio (es) was employed as an alternative parameter to express the compressive response of sand-tire crumb mixtures. It is seen that intergranular void ratio concept is a good indicator for understanding the behavior of sands with waste tire crumb.

One of the aims of modern laboratory studies is searching for dynamic parameters in a small strain of a soil. The reason behind this trend is the higher level of density of urban areas. City traffic, including trams, cars and subway trains, as well as certain types of construction works, can generate seismic waves, which cause a small strain between the soil and the structure to occur. This may lead to an exceeded limit serviceability state. The three main dynamic parameters of the soil are: Young modulus, shear modulus and damping ratio. Estimation of the cohesive soils damping ratio by two methods, namely free-vibration decay and half-power bandwidth, is the main goal of this article. The author performed his own research on two silty clay specimens in a resonant column. The conducted research show that the damping ratio obtained by using the half-power bandwidth method has significant error margin, which is equal approximately 50–60%, yet the curve shapes are very similar to the ones obtained by using the second method discussed in this paper. In author’s opinion, more research on cohesive soils has to be performed in order to introduce necessary corrections to half-power bandwidth equations.

The results of investigation on changes of groundwater corrosiveness during aeration were presented. The independent variables were air flow rate, aeration time as well as water layer height. The physic-chemical parameters of water for determining the changes of its properties using indirect methods were measured. The changes of water corrosivity were evaluated using Langelier Saturation Index (LSI), Ryznar Stability Index (RSI), Aggressiveness Index (AI), Index of Intensity (I) and Larson-Skold Index (IL). It was found that aeration substantially decreases the corrosiveness of water by increasing pH value and decreasing the concentration of aggressive CO₂^a. However, the very low alkalinity enables to achieve the non-corrosive properties of water.

The main issue considered in the article is to assess the process of aging and durability of uniaxial geogrids HDPE used for landfill to stabilize the slope. With the requirement to ensure the safety of geotechnical landfills follows the need to predict the behavior of geosynthetic materials at the design stage. To do this it is advisable to conduct laboratory testing of aging or accelerated aging of materials used for the implementation of geotechnical structures. The article contains an analysis of the mechanical properties of uniaxial geogrids subjected to accelerated aging in laboratory conditions. Methods of accelerated tests and the results of tensile strength using a broad sample uniaxial geogrids HDPE are discussed.

The purpose of the paper is the study of expediency and profitability of the modernization activities effected on the existing agricultural production building, completed in different times and using different construction technology. To assess the advisability of agricultural modernization of production facilities a scoring value method was developed, which allows a rapid assessment of the usefulness of the object to modernization. This method determines the degree of difficulty and allows for estimation of modernization cost based, inter alia, on data on the technical condition of the building and the role that object plays in building complex. The scope of the study includes objects that have been subjected to modernize, they are in its course and can potentially be modernized for the new technology standards. The analysis of the objects showed that modernization of agricultural production facilities is rational and economically justified action.

The article concerns a circular shell band and a circular arch; it includes a closed statics solutions of these structures which meet any system of boundary conditions which means ensuring cooperation with any building structure with a different shape. In the embodiment, the load was applied in the radial direction and in the direction perpendicular to the chord, applied to the curve. The amount of the internal forces complies with the internal and of the radius to the thickness of the band or to the height of the arch section depending on the opening angle of curvature.