Archives of Civil Engineering

The object of the present study is to investigate the influence of damping uncertainty and statistical correlation on the dynamic response of structures with random damping parameters in the neighbourhood of a resonant frequency. A Non-Linear Statistical model (NLSM) is successfully demonstrated to predict the probabilistic response of an industrial building structure with correlated random damping. A practical computational technique to generate first and second-order sensitivity derivatives is presented and the validity of the predicted statistical moments is checked by traditional Monte Carlo simulation. Simulation results show the effectiveness of the NLSM to estimate uncertainty propagation in structural dynamics. In addition, it is demonstrated that the uncertainty in damping indeed influences the system response with the effects being more pronounced for lightly damped structures, higher variability and higher statistical correlation of damping parameters.

Deriving the formulas for strain components, we are assuming, that cross-section of a rod being rotated in space during deformation does not need to be perpendicular to deformed centroid line. This not a quite intuitive assumption allows for more compact and easier formulas for strain tensor or equilibrium equations. Derived transformations between actual and initial coordinate system, components of strain tensor and virtual works principle for investigated spatially curved beams of bisymmetric cross-section are shown in this paper. Conformity with other models from referenced literature is also shown.

The research paper presents the results of the dynamic analysis of an existing bar dome subjected to wind loads. The calculation model of the structure was constructed using the finite element method. The dome was subjected to the standard wind pressure, assuming that it is operates in a harmonic manner. The numerical analyses were performed with the application of Autodesk Robot and MES3D. The analysis focused on the impact of selected factors such as the frequency of forcing, wind gustiness coefficient and structural damping on the behaviour of structures.

The paper presents some important aspects concerning material constants of concrete and stages of modeling of reinforced concrete structures. The problems taken into account are: a choice of proper material model for concrete, establishing of compressive and tensile behavior of concrete and establishing the values of dilation angle, fracture energy and relaxation time for concrete. Proper values of material constants are fix ed in simple compression and tension tests. The effectiveness and correctness of applied model is checked on the example of reinforced concrete frame corners under opening bending moment. Calculations are performed in Abaqus software using Concrete Damaged Plasticity model of concrete.

A large number of infrastructural concrete buildings are protected against aggressive environments by coating systems. The functionality of these coating systems is mainly affected by the composition and thickness of the individual polymeric layers. For the first time ever, a mobile nuclear magnetic resonance (NMR) sensor allows a non-destructive determination of these important parameters on the building site. However, before this technique can be used on steel-reinforced concrete elements, the potential effect of the reinforcement on the measurement, i.e. the NMR signal, needs to be studied. The results show a shift of the NMR profile as well as an increase of the signals amplitude in the case of the reinforced samples, while calculating the thickness of concrete coating leading to identical results.

The bonding state of the asphalt layers in a road pavement structure significantly affects its fatigue life. These bondings, therefore, require detailed tests and optimization. In this paper, the analyses of the correlation between the results of laboratory static tests and the results of fatigue tests of asphalt mixture interlayer bondings were performed. The existence of the relationships between selected parameters was confirmed. In the future, the results of these analyses may allow for assessment of interlayer bondings' fatigue life based on the results of quick and relatively easy static tests.

This article discusses an integrated concept of sustainable building and of Building Information Modelling (BIM) by means of implementation of the Green BIM management method. Apart from presenting this innovative project management method with particular attention paid to solutions applied by Scandinavian enterprises, the article aims at analysing institutional conditions regarding application of the Green BIM within Polish construction companies. Arguments presented in the article are based on results of a scientific review and industry specific publications. Moreover, the article discusses case studies of projects completed with the implementation of the Green BlM method.

The problems related to construction production are multi-faceted and complex. This has promoted the search for different methods/approaches for analizing the data which supports the decision-making process in the construction industry. In the article the authors focus their attention on well-known methods and tools, and on some new approaches to solving decision-making problems. The aim of the article is to analyze the methods used to analyse data in a construction company, convey their advantages and disadvantages, and specify the degree of efficiency in the discussed area.

The mining methods are classified as the methods of data analysis and the knowledge acquisition and they are derived from the methods of "Knowledge Discovery". Within the scope of these methods, there are two main variants associated with a form of data,
i.e.: "data" and "text mining". The author of the paper tries to find an answer to a question about helpfulness and usefulness of these methods for the purpose of knowledge acquisition in the construction industry. The very process of knowledge acquisition is essential in terms of the systems and tools operating based on knowledge. Nowadays, they are the basis for the tools which support the decision-making processes. The paper presents three cases studies. The mining methods have been applied to practical problems – the selection of an adhesive mortar coupled with alternative solutions, analysis of residential real estate locations under construction by a developer company as well as support of technical management of a building facility with a large floor area.

This paper presents a model of scheduling of multi unit construction project based on an NP-hard permutation flow shop problem, in which the considered criterion is the sum of the costs of the works' execution of the project considering the time of the project as a constraint. It is also assumed that each job in the units constituting the project may be realized in up to three different ways with specific time and cost of execution. The optimization task relies on solving the problem with two different decision variables: the order of execution of units (permutation) and a set of ways to carry out the works in units. The task presented in the paper is performed with the use of a created algorithm which searches the space of solutions in which metaheuristic simulated annealing algorithm is used. The paper presents a calculation example showing the applicability of the model in the optimization of sub-contractors' work in the construction project.

During the planning and controlling of the construction process, most attention is focu sed on risk analysis, especially in the context of final costs and deadlines of the investment. In this analysis, the primary and most significant concern is the proper identification and quantification of events, which on a certain level of probability may affect the development process. This paper presents the result of a risk analysis for a particular building object, made after completion of the investment and accepting it for use. Knowledge of the planned values and the actual investment process allowed for the identification of the events and their effects that in this case have significantly disrupted the investment process. The limited total cost of the investment project in question had a considerable impact on the progress of the project execution. Despite three transitions of administrative procedures, the opening date of the shopping centre was delayed by only three weeks.

This paper identifies the adverse events occurring during the execution of water supply and sewerage systems construction. The basis for this paper is research conducted in 2010-2014 on the construction sites of water supply and sewerage systems located in the provinces of Lower Silesia and Opole. The research consisted of direct observations of construction sites and review of construction documentation. It showed that work stoppages on the examined construction sites were frequent. They were caused by violations of work discipline by the production employees, adverse weather conditions, and defects in the project documentation. The study demonstrated that in almost every case, these bad an adverse effect on the completion date and budget of the investment. The analyses show that in such important and expensive investments as water supply and sewerage systems, organizational structures in which a special role is assigned to middle-rank personnel should be adopted.

The present paper concerns a problem of decisive criteria and their order in formwork selection problem. As the factors affecting the choice of exact form work system have been often discussed in literature, their importance has not been distinctly formulated yet, what hampers aiding formwork selection with MCDA methods that require criteria weights (eg.: SAW, TOPS IS etc.). Therefore, author ran a survey - the decisive criteria were recognized and verified within polls send to various contractors. An analysis of survey results including criteria ordering is a subject of the present elaboration.