In the structural reinforcement of a high-rise residential building in Changzhou city, Jiangsu province, China, the technology of prestressed steel bar strengthening shear wall, which was initiated in China, was applied. Combined with the engineering quality inspection report, the project characteristics and the requirements of the construction party, various methods, such as increasing cross-section reinforcement method and staged replacement concrete reinforcement method, were comprehensively used to treat and reinforce the structures with different quality problems and different parts. In general, the stress and strain of the newly added part always lags behind the stress and strain of the original structure. This will cause the stress of the original structure is too high and the deformation is large, while the stress of the new part is still at a low level, which cannot fully play its role and its due reinforcement effect. Prestressed steel bar reinforced shear wall technology, through the prestressed steel bar on the prestressed steel bar, which is a good solution to this problem, avoid the phenomenon of stress lag, and ultimately not only shorten the construction period of reinforcement, but also ensure the quality of reinforcement and user use area, successfully passed the reinforcement special acceptance. The monitoring data also proved that the reinforcement measures adopted are safe, reliable and economical. This paper can provide reference for the effective development of similar reinforcement projects.

Hundreds or even thousands of defects can be found during the building acceptance, hence the need for solutions which will facilitate the defect management, including identification, costing and repair. The aim of the paper is to present the possible use of BIM to support the defect management process during the acceptance of apartments in multifamily residential buildings. The paper presents a concept of quality control support application called MWBIM (Map of Knowledge BIM) which will collect data about discovered construction defects, their recording and servicing with the BIM technology. MWBIM will run based on Building Information Modelling (BIM), Augmented Reality (AR), Case-Based Reasoning (CBR) and maps of knowledge. There are three phases in the operation of the application: preparatory phase (planning the order of acceptance meetings and elements to be checked), acceptance phase (data collection and assigning them to the building information model) and the reporting phase (reports generation, assigning defects to contractors, follow-up of repair status). The intended uses of the application are mainly personnel involved in the acceptance of apartments.

Amount of works and activities tending towards defining new transport mode on the basis of the hyperloop system concept is growing significantly. They assume use of individual vehicles, offering space for several dozen passengers, running with speeds near speed of sound in a closed space with significantly lowered air pressure, utilizing magnetic levitation. Simultaneously it is fairly from economic point of view assumed, that first implementations should link locations between which traffic demand is expected to be very high. Assumed short spacing between hyper-vehicles, which are frequently declared to be ad-hoc adjusted to transport demand, to the knowledge of the authors gained in railway transport, seems to be in conflict with high speed safety related spacing in view of the line infrastructure capacity operational rules defined in the UIC (International Union of Railways) documents. That is the challenge, that formed the basis for authors’ investigations described in the paper. Several thesis regarding future new mode of transport based on hyperloop concept form an outcome of those investigations presented in conclusions.

This article discusses the rheological tests and analyses based on the Schapery non-linear viscoelasticity model that were performed to study asphalt mastic behaviour under high shear stresses. Seven mineral filler types were applied in this study, including a mixed filler with hydrated lime and fillers derived from dust extraction systems. Determination of basic properties of the fillers was followed by creep and recovery tests (DSR) at different levels of shear stress conducted in accordance with a modified MSCR procedure. The first stage in the analysis was the identification of linear viscoelastic region and the non-linear viscoelasticity model parameters such as the length of the loading period, the temperature and the stress level using TTSSP (Time-Temperature- Stress Superposition Principle). Subsequent numerical simulations of strain variation with respect to stress confirmed a high degree of agreement between the non-linear viscoelasticity model and mastic sample behaviour. A strong correlation was found between the non-linear viscoelasticity parameters and mastic properties. The proposed methodology is able to quickly identify and eliminate the fillers that may contribute to HMA deformations.

Columns perform a fundamental function in structures and studies on their reliability significantly impact structural safety. While the resistance and reliability models of rectangular reinforced concrete columns are addressed by many researchers, not much work has been done on the topic of columns with a circular cross-section. In this paper, a reliability model of resistance for circular reinforced concrete columns is formulated. A procedure for the representation of behaviour for short circular reinforced concrete eccentrically loaded columns is developed. It enables the consideration of many parameters including diameter of the column, concrete compressive strength, steel yielding strength, modulus of elasticity of steel, number of rebars, size of reinforcement, and position of bars in the cross-section given by the initial angle of rotation for the reinforcement. The representative design cases are selected for the most common four compressive strengths of concrete and five different reinforcement ratios. In total one hundred design cases are investigated. Statistical parameters of resistance, coefficient of variation and bias factor, are determined using the developed procedure and Monte Carlo simulations. A total of 10,000 full interaction diagrams of force and bending moment are generated for each design case. In each of the design cases, the failure zones are determined and the statistical parameters of resistance are calculated. The results are summarized in a table, presented in the forms of three-dimensional plots, and discussed. The study is performed based on American statistical data, materials and design codes.

Main goal of this paper is to present results of the numerical simulations of a real-scale gabion retaining wall tests. 4.5 m high wall was loaded and unloaded with water pressure, displacements of the crest of the wall were measured. Finite Element Method was used to simulate experiment and obtained results are compared with experimental ones. Usage of homogenized Coulomb-Mohr type continuum for gabions is proposed. Strength parameters of the model (cohesion and friction angle) are estimated on the base of large scale triaxial tests of the gabions and static tensile tests of the mesh. Influence of the “cut-off” condition on obtained results is analyzed. Elastic model for gabions is used for comparison of the results. Interface elements and truss joints between the gabions are used to simulate joints between gabions with limited strength. Good correlation between displacements obtained in experiment and numerical simulations was observed, especially in loading phase, so presented methodology of numerical modelling allows to model gabion retaining walls behavior close to the reality and could be used in engineering practice.

Recent research has shown that the increase in a number of participants of construction project elevated the cost and duration of construction. The use of integrated project delivery and the formation of a network organization structure can significantly reduce the costs, as the activities of the participants become more coherent and coordinated. The optimization of decisions is essential for the efficiency of a negotiation process, which in turn depends on the organizational structure. The article specifies three basic types of network organizational structure that can be applied in a construction project: focal (F1), dynamic (F2), multifocal (F3). In this study, a direct assessment of possible effectiveness of each of the three types of network organizational structures was carried out using a vector decision model. For each of the above-mentioned types of organizational structures, the potential effectiveness of negotiating act f0 and the total potential effectiveness F0 was calculated. The results of the study show that the most effective type of network organizational structure is the multifocal collective decisions in which a project manager has several “assistants”.

The paper presents the case study of geotechnical investigations reporting connected with expert’s opinion on undrained shear strength of organic sediments in the river valley at the north of Poland according to reinforcement methodology of c.a. 0,7 km highway embankment. Diversification of primary results caused additional research which revealed and confirmed liquid consistency of organic soils – several meters of organic and calcareous sediments – gyttja under the thin cover of peat. The main goal of the paper is a discussion on standardization of consistency of organic soils itself and additionally to point out very rare possibility of liquid consistency, finally not pointed in International Standards ISO 14688. The application of Atterberg limits in organic sediments is moot but even organic soil with water content higher than liquid limit can’t be classified and interpreted as very soft with description as soil which exudes between the fingers when squeezed in the hand. Such identification is practically impossible when it’s hard to squeeze because of gravitationally leaking through the fingers.

Investments in made ground are a big problem. The present investigation concerns ground derived from limestone treatment waste from SOLVAY soda plants. This waste is deposited in the southern area of Krakow in a reservoir called ‘White Seas’ in an area of approximately 15 ha. Currently, part of the route and tram investment, ‘The Łagiewniki Route’ Currently through the ‘White Seas’ area. The article presents an analysis of a section of this route by a high and steep slope made from made ground. The first stage of the in-situ measurements was to scan the shape of the high slope with the RIEGL VZ-400 terrestrial laser scanner. It was necessary to obtain the shape of the slope for numerical modelling using the FEM method. The point cloud perfectly reflected the shape of the slope with an accuracy of 5 mm. Soil samples (limestone waste) were also collected in the area of the slope for laboratory tests. In order to determine the effective strength parameters of the made ground of the embankment, a series of tests was carried out using triaxial compression apparatus. All triaxial tests were performed in accordance with British Standard 1337 Part 8. Modelling was performed using an FEM finite element method in MIDAS. The analyses also included the variant of irrigation of made ground. The conducted research shows that the high and steep slope made from calcareous waste indicates stability. The irrigated land did not make the high escarpment unstable.

In recent years, we have been able to observe a dynamic development of MCDA (multi-criteria decision analysis) methods, which have become widely used in various sectors, including construction. These methods are characterised by simplicity and one of their key advantages is their simple modelling of non-linear dependencies within decision problems and their analysis under the conditions of incomplete, uncertain and hard-to-measure information. The universality and simple use of these methods does not, however, free the decision-maker from the necessity to adopt the proper approach to modelling and analysing specific decision problems. To highlight the fact that it is the character of the problem that should determine the selection of the method of analysing it and not the other way around, the authors assessed the AHP (Analytic Hierarchy Process) and the ANP (Analytic Network Process) method in terms of verifying the impact of the different decision model structures on analysis outcomes and analysed their sensitivity to input data changes. This analysis was based on the example of selecting a telecommunications tower footing reinforcement alternative. The findings confirmed the significant impact of decision model structure on the ranking of the analysed alternatives.

Every day on roads many scenarios of accidents may occur. One of the measures to minimize their consequences is road safety barriers. Finite Element analyses are being increasingly used to support the physical testing of these devices. The paper addresses the issue of a secondary impact into the previously damaged w-beam guardrail system. This situation belongs to one of the most dangerous which can happen on roads and may cause serious hazards, especially if the vehicle goes through the barrier. To evaluate the crashworthiness of the road barrier, the computational model of the crash test was developed and validated against the full-scale crash test. Then two simulations of TB32 crash tests were conducted on both damaged and undamaged road barriers to assess the influence of damage on the effectiveness of the safety system during vehicular impact. The study has revealed that the partially damaged system preserved some of its original functionality.

The aim of the research is the laboratory investigation of steel-aluminium brackets employed to fasten lightweight curtain walls to building facilities. Static pressure, suction forces, and cyclic loads parallel to end plates (horizontal – to simulate wind influence) were applied in the study. The steel-aluminium brackets were tested on a reinforced concrete substrate made of C30/37 concrete class to simulate the real working conditions. Laboratory tests were performed to failure of the brackets or damage of anchoring fastened to the concrete elements. Additionally, the tensile capacity of stainless steel bolt connections screwed in aluminium profile was determined. The uniaxial tensile tests were performed for three length variants of the anchorage: 28 mm, 14 mm, and 7 mm of the stainless steel bars screw-in in threading aluminium profiles. In the course of cyclic tests, a hinge formed in the location of bolt connections made the change of the working character of steel-aluminium brackets. The cyclic tests also showed the danger of the strap aluminium profile displacement due to improper connection with the main aluminium profile. The paper is intended to provide scientists, civil engineers, and designers with an experimental assessment of mechanical properties of steel-aluminium brackets under static and cyclic loads.

Structural safety is a concept defined in various ways, usually in an imprecise and qualitative manner. The article refers to the more important concepts and methods of structural safety assessment and presents an original proposal for a multi-faced assessment of this feature. Suggested procedure allows to take into account most of the key properties determining the safety of structures, including reliability, risk, resistance and robustness, random and non-random uncertainty of state variables and assessment criteria, potential consequences of failure, and makes possible the visualization of the results. Using the concept of fuzzy numbers, fuzzy statistics and the approximate reasoning scheme it enable to take into account subjective and qualitative information about the state variables, safety criteria, computational method, the professional knowledge and intuition of the designer. The application of the proposed procedure is illustrated on the example of the safety assessment of a reinforced concrete beam designed for flexure. The proposed procedure may be useful at the stage of conceptual design of building structures, as well as for assessing the safety of existing structures.

In this work, safety analysis at the railway level crossings is presented using advanced mathematical modelling. Resistivity of track subgrade panels is taken into account. The analysis does not refer to the assessment of the current regulations. Specific cases of generalized dynamic system are considered by introducing operations S=Δ, S=P defined in space C(N) of real sequences. In this model, generalized discrete exponential and trigonometric functions that reflect the oscillatory nature of the analysed quantities are used. The advantage of the analyzes is the avoidance of numerical errors. We show also the importance of the resistivity of track subgrade panels in safety at the level crossings. The safety at the level crossings can be increased through providing track subgrade panels with appropriate resistivity to minimize negative effect of stray currents. The results may be used to evaluate selected safety indicators as well as to predict safety levels and to determine the ways of improving safety.

In this study, the effects of replacing fine aggregate by granulated lead/zinc slag waste (GLZSW) on the thickness of concrete shields against X-ray radiation and on the compressive strength of concrete have been investigated. The fine aggregate was substituted by GLZSW in four percentages: 25%, 50%, 75%, and 100% (by weight). The first aim of the present study was to compare the thicknesses of concretes with GLZSW and control concrete using Lead Equivalent (LE). The second aim was to assess the effects of replacing fine aggregate by GLZSW on the compressive strength of concrete. Results of this study indicated that the compressive strength of mixed concretes increased significantly compared to the control upon replacing fine aggregate by GLZSW; the mixture containing 100% GLZSW had the greatest compressive strength. Further, the inclusion of GLZSW as a substitute for fine aggregate increased the radiation attenuation properties and consequently decreased the thickness of concrete shields in direct proportion to the mixing ratio of GLZSW. The results revealed that concrete mixes containing 100% GLZSW offered the greatest reduction in shield thickness. The study shows that there is a promising future for the use of GLZSW as substitute for fine aggregate in concrete used to shield against X-ray radiation.

Double corrugated, self-supporting K-span arch structures are now commonly used globally to make roofs for building structures, as an alternative to traditional solutions. The K-span system has become popular mainly due to the simple and cheap method of its manufacturing and quick installation. Nowadays, new versions of the system are created but still there is no valid design method. Design difficulties are among the causes of failures or even collapses of such structures. Back in the 1970s, the first studies were developed concerning computational analyses of double corrugated arch roofs. They laid grounds for the development of contemporary K-span system technology but have since lost their practical advantages due to changing engineering conditions. The paper presents a review of research and computational methods concerning double corrugated arch structures. The paper discusses selected scientific studies, which were used as the basis for the development of research and computational methods, and their contemporary continuation. Directions for further research and analyses are also presented which could contribute to the future development of science and engineering in the area and could provide inspiration for future studies.

The paper examines the impact of possible operational factors on strength and frequency parameters generated by bending of fibre-cement panels. The tests were performed on elements cut out of a standard commercially available panel. The samples were exposed to factors described as environmental (soaking in water, bath-drying cycles, freeze-thawing cycles) and unique (flame ignition and high temperature exposure) and then subjected to three-point bending tests. Acoustic emission (AE) signals were acquired during the external load application. After the measurements were completed, the strength of individual elements was determined and the frequencies generated during bending were calculated. The obtained results were analysed statistically. Comparing the results obtained for a group of samples subjected to environmental and unique factors, significant differences between them were noted. It was noted that the decrease in the strength of the samples is related to the emission of lower frequency sounds. It was found that the application of the presented methodology allows to determine the condition of the fibre-cement boards in use.

Occurrences associated with the phenomena of climate change are increasingly visible. Effects of progressive environmental pollution are monitored with growing concern. Still, in the construction sector, the choice of sustainable materials and the knowledge concerning them is insignificant. Studies have shown that single-family residential buildings form the largest share of new buildings in Central European countries. It should be assumed that it is the improvement of this particular section of the construction sector to be the goal of further development of societies. This paper presents a case study of the construction of a house using straw - a material that, on the one hand, is a product associated with local tradition, while significantly reducing carbon footprint of its production and use, on the other. The construction of a prototypical house with the application of composite technology, i.e. timber framing with straw bale infill, was compared with a conventional method (ceramic masonry units) which is currently the most popular choice for building single-family houses in Poland. The study is based on the building’s life cycle assessment (LCA) over its consecutive phases as a tested and reliable method of the verification of a material’s impact on the environment.

Two-way curved arch bridges inherit the fine tradition of masonry structures, making full use of the advantages of prefabricated assembly, it adapts to the situation of no support construction and no large lifting machine and tools, and has the characteristics of convenient construction method and saving material consumption. In appearance, the two-way curved arch bridge has strong national cultural characteristics. The prefabricated components of the two-way curved arch bridge are fragmentary, complicated in bearing and poor in integrity. Most of the two-way curved arch bridges in service have been built for a long time and lack of maintenance and management. Increasing the cross-section reinforcement method is one of the two-way curved arch reinforcement methods. It has a significant effect, convenient construction, good rigidity and stability characteristics after the reinforcement. Through theoretical analysis, combined with a static load test results of the assessment of the bridge reinforcement effect. Through load test, it is found that the deflection of the arch rib after reinforcement is reduced by 9%~19% and the strain of the arch rib is reduced by 12%~22%. Through finite element calculation, the crack width of the reinforced arch rib decreases by 8.3%~14.2%. The results show that the stress and deflection are greatly improved by the method of increasing section.

The article presents the issue of container handling processes at a rail-road intermodal terminal. In the article, we have focused on the problem of a terminal layout design from the point of view of parking lots for external trucks. The main purpose of this article is the assessment of the necessary parking lots for the trucks considering daily turnover of containers and the trucks appointment time windows. We analyze how the length of the truck’s appointment time windows as well as the difficulties in containers loading operations and a number of handling equipment influence the necessary parking lots for trucks in the intermodal terminal. The trucks planned for loading of import containers may arrive at the terminal before the loading moment that is specified in crane operations schedule. The container handling time is given by a probability distribution. The equations defining the most important elements of the considered problem were presented in the general form. The special case of this model has been developed in the FlexSim simulation software. Based on the simulation research and calculations we pointed out that right truck’s appointment time windows can significantly reduce necessary parking lots at the yard. The literature analysis presented in the article indicates that most of the research in the field of intermodal terminal is focused on operations in container ports. There is lack of literature considering rail-road terminal layout planning in terms of the necessary parking lots and truck’s appointment time windows.

Concrete-filled steel tube arch bridge is filled with concrete inside the steel tube. The radial constraint of the steel tube limits the expansion of the compression concrete, which makes the concrete in the three-way compression state, thus significantly improving the compressive strength of the concrete. At the same time, it can simplify the construction process and shorten the construction period. Since the rapid development of concretefilled steel tubular tied arch bridge in the 1990s, a large number of such Bridges have suffered from the defects of steel concrete, loose tie rod, and hanger rod rust, etc. Therefore, the reinforcement technology for various diseases has been studied, among which the reinforcement technology for hanger rod replacement is the most complicated and more difficult. As more and more bridges of this type enter the period of reinforcement, it ismore and more urgent to study the reinforcement technology of suspenders. Taking a bridge that has been in service for 23 years as an example, this paper discusses the construction method and construction monitoring of replacing the suspender, so as to guide the construction monitoring of the bridge. Finally, the construction monitoring results of the bridge are given, which can provide reference for the replacement of the suspender of this type of bridge.

Incorporation of air-entraining agent has improved recycled concrete freeze-proof durability. However, it is very lacking to study the role of the entraining agent. In this paper, the influence of an air-entraining agent on freeze-proof durability for the ordinary C30 recycled coarse aggregate (RCA) concrete and air-entrained C30 RCA concrete was investigated with the laboratory comparative tests. The mass loss, the dynamic modulus of elasticity, ultrasonic wave velocity and cubic compressive strength were measured during freeze-thaw cycles. The test result showed the concrete’s performance was similar to the ordinary concrete and was better than that of other recycled concretes when the content of RCA was 50% and 0.03% of air-entraining agent was added for C30 RCA concrete. Meanwhile, the addition of air-entraining agent has an improved effect on the performance of recycled concrete, but the effect was limited.

Prediction of soft soil sub-grades settlement has been a big challenge for geotechnical engineers that are responsible for the design of roadbed embankment. The characteristics of low strength, poor permeability, high water contents, and high compressibility are dominant in soft soils, which result in a huge settlement in the case of long-term loading. The settlement prediction in soft soil subgrades of Jiehui Expressway A1, Guangdong, China, is the focus of this study. For this purpose, the necessary data of settlement is collected throughout the project execution. The numerical analysis is conducted by using the Richards model based on Linear Least Squares Iteration (LLS-I) method to calculate and predict the expected settlement. The traditional settlement prediction methods, including the hyperbolic method, exponential curve method, and pearl curve method, are applied on field settlement data of soft soil subgrades of Jiehui Expressway A1. The results show that the Richards model based on Linear Least Squares Iteration (LLS-I) method has high precision, and it has proven to be a better option for settlement prediction of soft soil sub-grades. The model analysis indicates that the mean absolute percentage error (MAPE) can be minimized as compared to other soft soil sub-grades settlement prediction methods. Hence, Richards's model-based LLS-I method has a capability for simulation and settlement prediction of soft soil subgrades.