Biperiodically stratified composites are characterized by two kinds of stratification which are realized independently on the micro-scale and mezzo-scale. An example of the above biperiodic structure is shown in Figure 1. The aim of the note is to propose a certain new general homogenization approach leading to effective heat conductivities as well as to illustrate this approach by some specific cases of stratifications.

This paper shows the analysis of the temperature boundary effect behavior in the dividing wall made of the conductor with bi-periodic material structure in which every surface parallel to the outside and the inside surface is bi-periodic. Conductor is made of a special case of hexagonal-type material structure. As a tool of modeling there has been chosen the tolerance averaging technique.

The study provides a solution that meets closed system boundary conditions on all edges of the shell. The solution is calculated under the theory of shells and all displacements and internal forces in any cross-section can be found. The size of the internal forces complies with the internal and external equilibrium.

The paper presents thesis which are the basis for development of new directions of in situ tests for assessment of structure and properties of the subsoil. New technologies were discussed, including Icone system in static penetration method by ap van den Berg from the Netherlands. The paper comments also constructions of hybrid systems for performance of static penetration tests with drillings and hybrid model of cylindrical penetrometer combined with seismic tests. New constructions for execution of seismic dilatometer tests on sea and coastal areas are also presented. The paper also discussed uncertainties of in situ and laboratory tests and its influence on the assessment of mechanical parameters of the subsoil.

The paper presents a description of in situ tests, which according to Eurocode 7 are required to recognize the geotechnical conditions of design structures and to determine the parameters of the ground in order to check the limit states. The developments of in situ testing methods including innovative changes introduced to the practice in recent years are also described. Moreover, an overview of the papers submitted to the conference ProGeotech2013 “Geotechnical design – investigation and selection of ground parameters”, session I: In situ tests according to EC7, with critical remarks for discussion at the conference session is presented.

The paper presents essential principals for the design of geotechnical construction in range accordance PN-EN 1997:2008 Eurocode 7-1. The design aspects of serviceability limit state in comparison with polish geotechnical standards were presented. The design aspects of spread foundations, pile foundations, retaining structures, embankment and slopes and influence of filtration phenomena were discussed. Generally principals of design geotechnical construction in Polish Standards was similar to principals EC 7, however proposed in EC 7 new more complicated coefficients of stability and increasing safety of design.

The paper presents the issues related to the methodology of laboratory tests in accordance with the recommendations of Eurocode 7 and complementary standards. The paper also discusses the papers submitted to the Session 2 “Laboratory tests according to EC 7” of the Conference ProGeotech 2013 “Geotechnical design – testing and selection of parameters” in terms of research and practical aspects.

In practice, there is the lack of a simple algorithm derived from the theory of the uncertainty for the development of the measurement results for concrete compression strength. The article presents several variants for estimating the uncertainty of measurement results of the surface pressure for cylindrical samples and their average compression strength. Developed formulas deal with standard cylindrical samples and core samples coming from walls in concrete construction. In addition, it has been shown what is the impact of adopting the accuracy of the mathematical constant,π and measured diameter on the uncertainty results of the cross-sectional area of cylindrical samples, and consequently also the results of the average compressive concrete strength. Presented analysis showed that during application of typical compression machines (class 0.5 and 1) in concrete study the uncertainty of designated strength depends mainly on the accuracy in measuring the diameter of the samples and the accuracy of the determination of the surface pressure. In the light of the above, the guidelines contained in the standards for determining the diameter of the samples with an accuracy of 0.5% size (e.g. 100 mm ±0.5 mm) and determination based on the cross-sectional area – is insufficient. In the case of samples having a diameter at least 100 mm, it is recommended to set it with an accuracy of ±0.1 mm using resolution of calipers 0.01 mm.

In the design European standards ISO 4356 i PN-EN 1992-1-1 PN-EN 15037-1 checking deflections of RC bending floor elements was brought about for showing permissible values and overviews of computational methodology. Rigorous requiring the verification of deflections due to the possibility of damage to nonstructural and finishing elements adjoining e.g. to floor elements losing shape and the lack of the legible computational algorithm caused the custom, existing in the environment design, of dimensioning of elements of the load-bearing system at assuming permissible leff /500 values. So a conservative approach in checking the deflection limit state, itself without any-age based on merit, consequently generates unwarranted oversize bending elements of the supporting structure and a substantial increase in the cost of execution of the works.

The paper analyses solutions of deep excavation by diaphragm wall with struts on the example of planned investment on the Tamka street in Warsaw. Conducted calculation of the internal forces and displacements using the Blum and beam on elastic foundation methods. Possible ultimate limit states were verified. Analyze of ground surface settlement and its impact on adjacent building based on empirical formulas was also done.

Analysis of 38 rainfall-runoff events, recorded in a small urban catchment (A = 28.7 km²), located in south-west part of Warsaw, in the period of 2009–2012, has been carried out with the aim of estimating the lag times, and checking they variability. The lag times of recorded events were compared with the estimated ones from empirical formulae. Results of analysis indicated significant variability in lag times among the events (since 1.77 to 15.8 h). Relations between lag time and event characteristics used in selected formulae were not confirmed by the recorded data.

The paper analyses an impact of dimensions of vertical and horizontal screens on slope stability of a levee. The calculations were performed for one of the cross-sections of the River Warta right levee near the city of Poznań. The optimized dimensions of levee and subsoil screens result also from the influence of screen length assessment on safety factor. Three variants were analysed: vertical screen in the subsoil, located at the toe of upstream slope combined with a screen on the upstream slope, horizontal screen (blanket) connected with a screen on the upstream slope and vertical screen made from crest of levee.