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The issues associated with freezing and thawing of soils in the subsoil of a complex of port facilities including transport infrastructure have been considered. The solution of thermal-physical problems of freezing, frost heave and thawing of soils has been made in spatial domain; the results of calculations are compared with the practical values. Numerical simulation of the problem of stability of structures on permafrost soils allowed predicting a possible soil thawing depth in time and optimizing the use of modern thermal insulation materials. The proposed calculation methods will provide reducing cost of development of transport infrastructure and port facilities under construction in the important northern regions of Russia.

Cross-laminated timber (CLT) is currently a highly efficient material for the bearing structures of timber buildings. The combination with concrete in composite cross-section disposes of many advantages. The paper analyses some of the available analytical calculation procedures for determining the bending resistance of these multilayer laminated panels. The aim is to assess their suitability for the determination of the resistance of composite CLT-concrete beams, where concrete and wooden layers are connected rigidly by adhesive.

The purpose of this article was an attempt to compare selected calculation methods regarding shear strength in reinforced and prestressed concrete beams. Several calculation methods were tested. This included codes: PN-EN 1992-1-1:2008 [1] , ACI 318-14 [2] and fib Model Code for Concrete Structures 2010 [3] . The analysis also consists of methods published in technical literature. Calculations of shear strengths were made based on experimental works found in literature. The shear strength ratios V test /V calc were chosen to be the yardstick of comparison, where V test is the experimental shear strength and V calc is the calculated shear strength. A wide range of variables including shear span/depth ratio, compressive strength of concrete, longitudinal steel percentage helped to verify the applicability of calculation methods. Although most of authorial techniques proved to be unstable, they succeeded to show that codes’ formulas for calculating shear strength could still be improved.

As the crosstie beam in railway track systems, the prestressed concrete sleepers (or railroad ties) are principally designed in order to carry wheel loads from the rails to the ground. Their design takes into account static and dynamic loading conditions. It is evident that prestressed concrete has played a significant role as to maintain the high endurance of the sleepers under low to moderate repeated impact loads. In spite of the most common use of the prestressed concrete sleepers in railway tracks, there have always been considerable demands from rail and track engineers to improve serviceability and functionality of concrete sleepers. For example, signalling, fibre optic, equipment cables are often damaged either by acute ballast corners or by tamping machine operation. There has been a significant need to re-design concrete sleeper to cater cables internally so that they would not experience detrimental or harsh environments. Accordingly, this study is the world first to experimentally investigate the effects of holes and web openings on structural behaviours of concrete sleepers under rail loading condition. The modified compression field theory for ultimate strength behaviours of concrete sleepers will be highlighted in this study. The outcome of this study will enable the new design and calculation methods for prestressed concrete sleepers with holes and web opening that practically benefits civil, track and structural engineers in railway industry.

The design of modern and architecturally complex constructions in civil engineering can only be effectively achieved through the application of Computer-Aided Engineering (CAE). This requires, on the one hand the use of fully 3D CAD Systems during the architectural design process and on the other hand the use of fully 3D numerical calculation methods like the Finite Element Method (FEM) during the engineering construction process. The combination of the aforementioned CAE methods allows for the development of highly sophisticated structures. The practical application of these methods will be revealed by examining the floating stages of the lake festival in Bregenz/Austria, these stages are designed and built anew every second year. The aim is to show the development process from the initial designs up to the finished stage; a process made possible thanks to a close collaboration between designers and engineers.

There is a variety of MCDM methods of solving decision related problems that can by used. Only a combination of normalization and calculation methods is feasible if problems are solved which are to become a foundation of a rational decision. Normalization methods are used in decision-making processes in various fields. Many researchers apply normalization methods in civil and construction engineering and management. Reviews of normalization methods used in construction engineering and management, and their applications there are presented in the paper, as well as a review of research collaboration, achievements, academic activities, and information about one of the founders of the German-Lithuanian-Polish colloquium - Professor Friedel Peldschus. Information about Professor Friedel Peldschus, presented in the paper, has been taken from different date bases which evaluate research work.

The calculation of building energy consumption is needed in all architecture design projects. Building simulation software is used to predict the indoor air temperature and relative humidity as well as the building's heat loads. The calculation of accurate heat load requires calculating coupled heat and moisture transfer in building envelopes and the hygrothermal interactions between the envelopes and the environment. However, the moisture effects of building envelopes are often neglected. This would bring much inaccuracy to the simulation results. Based on different calculation methods, many numerical building energy simulation programs have been developed. This paper evaluates the accuracy and the applicability of three thermal models in EnergyPlus (CTF-Conduction Transfer Function model, HAMT-Combined Heat and Moisture Transfer model, EMPD-Effective Moisture Penetration Depth model) for calculating moisture effects on building energy consumption in different climate conditions. The effects of different room infiltration rate on the accuracy of different models are also analyzed.

The calculation methods for assessing the fatigue life of welded structures are gaining increasing importance in many technical applications, since they contribute in the decrease of the development costs and time. In various engineering applications, especially in the commercial vehicle sector with thick and thin components and welds of complex geometry and loading configurations, there is still a lack of experimentally verified guidelines for the calculation of fatigue life. The present paper shows an advanced procedure for FE modeling and fatigue life calculation of welds based on the Notch Strain Approach. It uses elastic-plastic cyclic material properties and can be applied in early stages of development when prototypes are not available. It can be applied to continuous and non-continuous welds, e.g. ones with pronounced terminations. Due to its local character, it covers both weld toe and root failures. To verify its accuracy, the proposed calculation procedure is applied to serial motor truck's rear axles providing complex 3D weld geometries subjected to cyclic loading. Calculated lifetime results are compared to experimental ones determined on a test rig. The agreement is satisfactory.

The performance and faults diagnosis research on Proton Exchange Membrane Fuel Cell (PEMFC) provide a reliable theoretical and technical support for its commercialization. Meanwhile, PEMFC research based on modeling, which uses the commercial software such as Fluent, SIMULINK etc, affords a theoretical foundation for guiding the experiments and testing the new numerical calculation methods. Hence, based on a single cell 3D (three-dimensional) PEMFC model, the paper studied the performance impacts of physical parameters, such as porosities of GDL, and physical structure, such as the thickness of GDL. Additionally, from the aspect of operating conditions, the cathode gas supply shortage fault is analyzed to study the influence on PEMFC output voltage.

The paper discusses origins of fatigue data used for evaluating the prediction quality of various multiaxial methods intended for estimating the fatigue limit. The paper defines some requirements useful for processing similar data sets. It focuses on four most often used data sets, analyzes the way they were prepared and the way they are transmitted over various research papers. These sets are commented and objections to some their items stated. Weight coefficients enabling their application in validation studies are proposed. The final reduced total set has approximately one half of its original size. The reduced set is re-analyzed by several fatigue limit calculation methods and the results are compared to the origin. Though the relative probability distribution of the output is quite well kept, the importance of evaluating the second hand data sets carefully is clearly highlighted.

To simulate shear wall of tall building structures, some kinds of calculation methods towards Multi-Vertical-Line-Element Model are discussed in detail. A more reasonable element stiffness matrix and a improved Multi-Vertical-Line-Element Model are given. Combined with hysteretic axial model and hysteretic shear model, nonlinear analysis of a shear wall is put through. The calculation result indicates that the improved model has relatively well accuracy compared with test result.

To improve computational lifetime calculation methods, a component specimen named “W-Link” is generated from the Ti-alloy Ti-6Al-4V. Based on specimen tests, S/N-curves were evaluated and integrated in the lifetime calculation program FEMFAT. Whereby, life time estimation for the component is made possible. In order to compare lifetime calculation to lifetime in reality, component tests were carried out. In this way not only the simulation of the lifetime and real tests on specimens are shown, also the transferability of specimen results to component is presented. Finally, fracture analysis and comparison of the different specimens is carried out.

Due to risks and uncertainties associated with construction projects, owner agencies usually add a reserve amount to the estimated project cost. This reserve amount, known as contingency, is to absorb the monetary impact of the risks/uncertainties and to prevent cost overrun. Over the past two decades, many contingency calculation methods for construction projects have been introduced by practitioners and researchers. These methods can be ranged from simply considering a percentage of the project base cost to complex mathematical methods. Each of these methods suggests an approach for calculating contingency using different assumptions. The question is which one of these methods should be applied to a certain project at a specific phase. Knowing the advantages and disadvantages of each method can help practitioners in construction industry select the best method based upon their project characteristics, budget, and time. This paper compiles almost all contingency calculations methods and divides them into three main categories of: (1) deterministic methods, (2) probabilistic methods, and (3) modern mathematical methods. Each of these categories are then divided into more subcategories and discussed in detail.

Research on channel bed profiles is one of the basic topics of river dynamics and fluvial process studies, since it was closely associated with the problems such as turbulent structure, flow resistance and sediment transportation in alluvial rivers. As a result of motion water flow interacting with sediment, channel bed profiles have irregular plane structures and self-similar microstructures, which were better analyzed by fractal method to reflect the intrinsic rough characteristics. In this study, several existing fractal dimension calculation methods were compared quantitatively, along with the discussion of their non-scale zones, correlation coefficients and computational accuracies. The following methods are included in this paper: Yard Stick Method, Box Counting Method, Variation Method, Structure Function Method, Root Mean Square Method and R/S Analysis Method. Finally, it is suggested that the Structure Function Method is suitable for calculating fractal dimension of rough channel bed profiles, which can provide references for future micro-fractal studies on fluvial process, flow resistance and waterway regulations.